THE TRANSCRIPTOME OF QUIESCENCE AND DORMANCY IN ... · the transcriptome of quiescence and dormancy...
Transcript of THE TRANSCRIPTOME OF QUIESCENCE AND DORMANCY IN ... · the transcriptome of quiescence and dormancy...
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THE TRANSCRIPTOME OF
QUIESCENCE AND DORMANCY IN
SUBTROPICAL AND MEDITERRANEAN
GRAPEVINE
Presented by:
Sandra Patricia Agudelo Romero, PhD.
MASTER OF SCIENCE IN BIOINFORMATICS
AND COMPUTATIONAL BIOLOGY
NATIONAL HEALTH RESEARCH INSTITUTE
INSTITUTE OF HEALTH CARLOS III (ISCIII)
2014-2015
UNIVERSITY OF WESTERN AUSTRALIA
Professor Dr. Michael Considine
2nd of February of 2015
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CONTENTS
DEDICATION ii
ACKNOWLEDGEMENT iii
1. ABSTRACT 1
2. THE APPROACH TO THE PROBLEM 2
3. OBJECTIVES 3
4. INTRODUCTION 4
5. MATERIALS AND METHODS 6
5.1. Sample collection 6
5.2. RNA extraction, Illumina library construction and sequencing 6
5.3. Data processing analysis 6
5.4. Functional enrichment analysis 7
6. RESULTS AND DISCUSSION 8
6.1. Dormancy and Quiescent Gene Expression Profiles 8
6.2. Transcriptional Bases for Bud Dormancy and Quiescent
Differentiation Between Climates. 12
6.2.1. Pre-chilling 12
6.2.2. Post-chilling 18
6.3. Finding Potential Biomarkers 22
7. CONCLUSIONS 26
8. BIBLIOGRAPHY 27
9. ANEXOS 33
9.1. FastQC command line 33
9.2. Trimmomatic command line 33
9.3. Kallisto on hiseq command line 33
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DEDICATION
For the two great loves of my life,
thank you so much for existing.
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ACKNOWLEDGEMENT
I was supported by an Australian Research Council grant (ARC: LP130100347). The
research was supported by the ARC grant: LP0990355. This project was carried out at
the University of Western Australia in the ARC Center of Excellence in Plant Energy
Biology.
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1. ABSTRACT
Vine physiology is dependent on climate for orderly transitions between vegetative and
reproductive growth. Productive viticulture requires a temperate/Mediterranean climate,
while in warmer, low latitude climates. Low latitude viticulture is only viable for table
grapes if development is intensively managed with chemical and physical stress
treatments, such as deficit irrigation to force a ‘rest’ period and cyanamide to force bud
burst. Even with intensive management, vine growth is disorderly and yields are
considerably lower and more variable, as the seasonal cues that grapevine relies on for
developmental transitions are lacking. To gain insight into how differences in the
temperature due to climate features can modify grapevine bud dormancy, a RNA-seq
study was performed to investigate differences between subtropical and Mediterranean
climates in table grapes (Flame Seedless).
For this, gene expression changes in buds from two adjacent vineyards in subtropical
Western Australia (25°S latitude) were compared against one vineyard in a
Mediterranean climate (32°S). Buds were collected for differential expression analysis
at the end of summer (March; henceforth termed pre-chilling) and in mid-winter (June
henceforth termed post-chilling), over two successive years (2012 and 2013). Principal
Components Analysis (PCA) of RNA-seq data revealed that the main factor explaining
the global gene expression differences was between consecutive years.
Differential expression analyzes of subtropical and Mediterranean climates comparison
in pre-chilling and post-chilling conditions were carried out (1% FDR and FC |3-fold|).
Cluster and functional enrichment analyzes were then performed to each condition. In
the comparison performed during pre-chilling, WRKY family transcription and
oxidative stress (Glutathione S-transferase) categories showed differences between
climates. Whereas in the post-chilling condition was detected ethylene-mediated
signaling pathway and C2C2-YABBY family transcription factor categories.
This work provides a global view of major transcriptional changes taking place in
Australian subtropical and Mediterranean climates, highlighting those molecular and
biological functions that showed differences between climates, suggesting a main role
of those functional categories during regulation of bud dormancy.
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2. THE APPROACH TO THE PROBLEM
Grapevine cultivation in subtropical climates is a fragile system requiring intensive
management, for which there are no biological markers. Miss-timing intervention can
result in phytotoxic effects, as in the case of the dormancy-releasing hydrogen
cyanamide. In temperate-grown grapevine, the reproductive and metabolic cycles are
regulated by environmental signals, particularly the induction of dormancy during
autumn and the subsequent re-activation of growth during spring (Lavee et al., 1997).
Like many woody perennials, energy reserves accumulate in the perennial tissues prior
to the onset of dormancy and their mobilisation entirely supports the initial stages of
vegetative and reproductive growth in spring (Lebon et al., 2005). Hence, the dormant
phase is necessary for coordinated, productive and sustainable growth (Lavee et al.,
1997). In grapevine, molecular investigations of dormant axillary buds have also
revealed coordinated profiles, including reprogramming of carbohydrate metabolism,
but these have been under temperate conditions and confined to dormancy release (bud
break), a single event in a complex reproductive cycle (Mathiason et al., 2008). Here,
the reprogramming of buds during dormancy and quiescent (latent) stages can be
studied using RNAseq approach. For this, buds sampled from a subtropical Western
Australian climate (Carnarvon) were compared to buds from a Mediterranean climate
(Swan Valley, Perth) (Figure 1).
Figure 1. Map of Australian grape growing regions and temperature differences. A. Subtropical Western
Australian climate (Carnarvon) and Mediterranean climate (Swan Valley, Perth) are highlight.
Subtropical climate is represented by Bumbak (B) and Condo (C) sites from Carnarvon. Mediterranean
climate is represented by Nuich (N) from Swan Valley (Perth). B. Graphics showed the average of the
differences in temperature of both climates provided by the airports (Carnarvon and Perth respectively) in
the last decades.
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3. OBJECTIVES
The aim of this project is to determine the relationship between climates in grapevine
buds grown in a subtropical region (Carnarvon, WA) and a Mediterranean climate
(Swan Valley) in Australia during two consecutive seasons (2012 and 2013) by using of
RNAseq technology.
Specifically:
To dissect the effects and interactions between climate conditions through their
gene expression profiles.
To finding potential gene candidates in order to be used as biomarkers for
anticipate actions in warm-temperate or stressed conditions (i.e. water stress).
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4. INTRODUCTION
Grapes (Vitis spp.) are economically the most important fruit crop worldwide with a
global production of around 67 million t in 2012 (Food and Agriculture Organization
Corporate Statistical Database (FAOSTAT, 2014,
http://faostat.fao.org/site/567/default.aspx#ancor). Table grapes rape and processed
products such as: wine, juice, jam and dried fruit, represent an important sector in the
global market. Moreover, their consumption has an important added value in a healthy
diet by the polyphenolic compounds with antioxidant and anticarcinogenic properties
found in them (Ali et al., 2010).
Therefore, it is important to understand how improve the production of grapes in
Australian subtropical climate since theoretically, this region lacks sufficient
temperature to regulate dormancy correctly. This fact is a critical environmental
requirement for sustainable table grape production of cultivars as Flame Seedless.
Dormancy induction is problematic and the normal reproductive cycle is perturbed, with
a shifted and condensed phenological cycle. It is only management intervention that
sustains this cycle; vines would otherwise continue vegetative growth throughout
winter, limiting resource storage and resulting in variable yields and very short vine life
(Possingham 2004). In subtropical climates, sustainable production thus relies on
management intervention to supplement for environmental signals; e.g. water stress and
chemical application (concentrated nitrate) to force leaf fall, imposing a winter “rest,”
and pruning/ chemical application (hydrogen cyanamide) to stimulate vines to
recommence vegetative and reproductive growth. Even with interventions, disorders are
common, as described in the predominant subtropical viticulture regions; Carnarvon
(WA) and Rockhampton (Qld) in Australia, Coachella Valley (California), Mexico,
Northern Chile and Orange River (South Africa):
• Slow and erratic bud burst and extreme dominance of the apical buds.
• Delayed foliation following bud burst, often characterised by a period of
chlorotic growth.
• Inflorescence disorders, resulting in partial or complete abortion or abscission.
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Each of these disorders may co-occur. The result is an industry faced with high
prospects but equally high input costs and yield and quality variation. To date, R&D
into production of temperate fruit crops in subtropical or tropical climates has focussed
heavily on improving bud burst, principally through optimal use of chemicals or
through manipulating the microclimate during autumn (Possingham 2004). There is a
distinct lack of research on the stages of bud development preceding winter, so-called
dormancy onset.
In this project, to gain insight into how differences in the temperature due to climate
features can modify grapevine bud dormancy, a RNA-seq study was performed to
investigate differences between subtropical and Mediterranean climates in table grapes
(Flame Seedless). Differential expression in pre-chilling and post-chilling conditions
were carried out (1% FDR and FC |3-fold|) accompanied of a cluster and enrichment
analysis.
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5. MATERIALS AND METHODS
5.1. Sample collection
Field collection in Western Australia (WA) of grape table, Flame seedless, was done at
two sub-tropical vineyards (B and C) in Carnarvon (24.9ºS and 113.7ºE) and a
Mediterranean vineyard in the Swan Valley (31.8ºS and 116ºE). Sampling was
performed between the end of March and early April for the pre-chilling condition and
in the middle of June for the post-chilling condition. Every sample was composed of
two buds randomly selected from healthy canes, they were immediately frozen in dry
ice and stored at -80ºC. At the time of sampling, buds were cut from the cane with a
scalpel, visually assessed for indications of necrosis from beneath the bud; buds with
obvious visible signs of necrosis within were discarded, however this assessment cannot
determine less dramatic levels of necrosis within the bud. For each time point and place
three/four biological replicates of buds were sampled for the RNA-seq analyses.
5.2. RNA extraction, Illumina library construction and sequencing
Buds were ground under liquid nitrogen to a fine powder. Total RNA extraction was
performed using the Spectrum Plant Total RNA kit with an on-column DNase treatment
according to the supplier’s instructions (Sigma-Aldrich, Castle Hill, Australia),
followed by an isopropanol/acetate precipitation. The quality and integrity of the
isolated RNA was tested using a NanoDrop 100 spectrophotometer and agarose gel
electrophoresis. Only RNA with an Abs260 nm/Abs280 ratio above 1.95 was used
further. RNA-seq libraries were prepared with the TruSeq Stranded Total RNA with
Ribo-Zero Plant kit according to manufacturer's instructions (Illumina, Scoresby,
Australia). Sequencing was performed on an Illumina HiSeq1500 instrument as 100bp
single-end runs.
5.3. Data processing analysis
Resulting reads were aligned to the whole 12X V1 Vitis vinifera PN40024 reference
genome (Jaillon et al., 2007) with Kallisto (Bray et al., 2015). Gene expression profiling
was carried out using edgeR (Robinson et al., 2010) and limma (Ritchie et al., 2015)
Bioconductor packages. The counts matrix obtained with Kallisto was read using
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edgeR, it was converted into a DGEList data class and a TMM normalization method
was applied to obtained the log2 Counts-Per-Million (logCPM). Then, a Voom
transformation was applied to convert it into a EList object to can use limma pipelines
for differential expression under a linear model. To identify differentially expressed
genes, a multiple testing correction via False Discovery Rate (FDR) was performed
(P<=0.01) along with fold change (FC 3-fold). Principal component analysis (PCA) was
performed with the full TMM dataset using Acuity 4.0 (Axon Molecular Devices,
http://www.moleculardevices.com). FastQC, Trimmomatic and Kallisto command lines
used to generate the count matrix are detailed in Anexos.
5.4. Functional enrichment analysis
Gene lists were analysed further with FatiGO (Al-Shahrour et al., 2004) to identify
significant functional enrichment in Babelomics 5 (http://babelomics.bioinfo.cipf.es/)
following a grapevine-specific functional classification of 12X V1 predicted transcripts
(Grimplet et al., 2012). Fisher’s exact test was carried out in FatiGO to compare each
study list with the list of total non-redundant transcripts housed in the grapevine 12X
V1 gene predictions (Grimplet et al., 2012). Significant enrichment was considered for
P<0.01 after Benjamini and Hochberg correction for multiple testing.
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6. RESULTS AND DISCUSSION
6.1. Dormant and Quiescent Gene Expression Profiles
As a first approach to analyze the complexity of the gene expression dataset of the
present research, a principal component analysis (PCA) was performed over the
expression data of the dormancy and quiescent stages in two climates (Subtropical and
Mediterranean) during two consecutive seasons. The first, second and third principal
components (PC1, PC2 and PC3) explained together 45.06% of the variability in gene
expression (19.31%, 14.26% and 11.49%, respectively) (Fig. 2A). The results of the
PCA plot showed consistency across biological replicates and seasons, therefore, the
experiment was considered highly reliable for further analysis. Experimental
consistency allowed for exploring PC3 further in a hypothesis-free approach, as this
component discriminated the two consecutive years (Fig. 2B).
To further analyze the biological basis of the patterns observed in the PCA plot,
transcripts that mostly contribute to component PC3 were identified. This was done by
considering the PCA loading scores (LS) for all the transcripts in PC3 (Table SX). The
LS absolute value cut-off of five was considered to identify transcripts dominating PC3.
In this manner, PC3 was dominated by transcripts up-regulated (PC3 LS > 5) more than
down-regulated (PC3 LS < −5), 192 and 122 transcripts, respectively (Table SX).
This difference suggests that seasonality (annual variation) is the major factor between
climates and dormant stages (pre- vs post-chilling). The top three of positive ranking
(PC3 LS > 5) was formed by genes that coding for DNA-directed RNA polymerase
subunit beta (VIT_11s0103g00390), Kinesin family member 5 (VIT_14s0128g00090)
and MAP3K delta-1 protein kinase (VIT_00s0230g00140). They belong to RNA
polymerase, Microtubule-driven movement and MAPK cascade processes, respectively.
On the other hand, the negative ranking top three (PC3 LS > -5) was formed by genes
that coding for Pentatricopeptide (PPR) repeat-containing protein
(VIT_17s0000g06390), MAPK (MPK6) (VIT_05s0094g00900) and Brassinosteroid
insensitive 1-associated receptor kinase 1 (VIT_00s0472g00020). Those transcripts
correspond to Pentatricopeptide domain family, Ethylene-mediated Signaling pathway
and Brassinosteroid-mediated
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A. B. C.
Figure 2. PCA plot of ‘Flame Seedless’ bud samples according to their expression data in 2012 and 2013 seasons, buds were harvested from two adjacent vineyards in
subtropical Western Australia (25°S latitude) and one vineyard in a Mediterranean climate (32°S). A. PCA plot of buds samples according to their TMM normalized
expression data. The first (PC1), the second (PC2) and the third (PC3) principal components are represented. Each season is formed by two stages of dormancy (pre- and post-
chilling) with three or four replicates. Green, 2012 season and orange, 2013 season. B. Stage averaged PC3 loading scores. Color code is the same as in A. Lines represent
standard errors (SE). C. Functional categories over-represented in PC3 (B). Absolute values of log10 transformed P-values were used for the bar diagram representing
statistical signification, only categories with P-values < 0,01 are shown. Clear blue, Primary metabolism and dark blue, secondary metabolism.
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Signaling pathway, respectively. Therefore these transcripts summarize the major
differences between years.
Functional enrichment analysis was carried out using FatiGO (Al-Shahrour et al, 2004)
to assess the biological significance of the transcripts showing a higher contribution to
the expression variability. The lists of transcripts most contributing to PC3 were
compared to the rest of the transcripts represented in the 12X V1 predicted transcripts
(Grimplet et al., 2012), highest scored (LS > |5|) transcripts were analyzed together.
This functional analysis discriminated just two functional categories: Primary
metabolism and Transport overview (Fig. 2C). Four processes associated to Primary
metabolism were found: ‘respiratory-chain phosphorylation’, ‘nucleic acid metabolism’,
‘protein processing in endoplasmic reticulum’ and ‘ribosome’. Two processes were
detected in Transport overview: ‘proton-translocating NADH Dehydrogenase’ and
‘proton-translocating Quinol:Cyt c Red’.
Among all processes, ribosome-related processes had the most highly significant adj. P
value (8,38E-11). The eukaryotic ribosome is a complex structure formed for four
rRNAs and about eighty ribosomal proteins. It represents a crucial piece of the cell
machinery, responsible for protein synthesis, and as such plays a major role in
controlling cell growth, division, and development. Several studies have reported that
genetic defects in ribosomal components can produce deleterious effects on the
development and physiology of drosophila, mice, humans and plants (Barakat et al.,
2001). On the other hand, it was also reported a positive correlation between the level of
r-protein gene transcript accumulation and cell division in suspension culture cells and
tissues such as auxin-treated hypocotyls, apical meristems, young leaves, and lateral
roots (Barakat et al., 2001). Here, two Ribosomal RNAs were detected: 23S
(VIT_01s0010g01260; VIT_11s0037g01180 and VIT_12s0035g02010) and 16S
(VIT_13s0101g00220) along with fifteen ribosomal proteins.
To dissect the influences of consecutive seasons, PCA analysis was performed
separately for each year. Each analysis represents two sites: Subtropical site (B -
Bumbak and C - Condo) from Carnarvon and Mediterranean climate (N - Nuich) from
Swan Valley, they represent subtropical and Mediterranean climates, respectively.
Additionally, two stages of grapevine bud development were compared, pre-chilling
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and post-chilling, these stages correspond to dormant and quiescent buds, respectively
(Fig. 3A and 3B.). Two different signatures in the TMM normalized expression data
resulted. In 2012, transcriptomes segregated by climates but not by time-of-sampling
(Fig. 3A), while 2013, transcriptomes segregated by time-of-sampling rather than
climate (Fig. 3B. In 2012, PC1 and PC2 explained together the 43.26% of the variability
in gene expression (23.66%, and 19.60%, respectively); whereas in 2013, they
explained together the 45.22% of the variability in gene expression (PC1 - 28.06%, and
PC2 -17.16%) (Fig. 3A and 3B).
Figure 3. Bi-dimensional loading score plot resulting from PCA analysis detailed by seasons (A and B)
along with their differentially expressed genes (DEGs) (C and D). A. and B. PCA plots showing
transcriptional discrimination in places of harvest and developmental stages for 2012 and 2013,
respectively. Percent of variation explained by each PC are shown in brackets. Replicate samples for the
same time-point are in the same color. Letter B, C and N refer to the site of harvest, subtropical sites B
and C, and Mediterranean site N. Pre refers to the pre-chilling stage and Post to post- chilling. C. and D.
bar plots display the distribution of DEGs under a FDR (0,01) and FC |3-fold| cut-off. Green, lower
expression; magenta color, higher expression.
Gene expression analyses were then performed to study the differences between
climates corresponding to two different latitudes, subtropical Western Australia climate
(25°S latitude; Carnarvon; B - Bumbak and C - Condo) against Mediterranean climate
(32°S; Swan Valley; N - Nuich). The two subtropical sites were individually compared
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to the Mediterranean site. In parallel, differences in the stage of bud development;
dormancy (pre-chilling) and in quiescence (post-chilling) were considered.
Differential expression analysis was performed with the Bayes t-statistics from the
linear models for microarray data (limma) (1% FDR and FC |3-fold|). Functional
annotation was assigned to the core set of genes that matched a putative molecular
function (Grimplet et al., 2012), 2238 transcripts in the case of 2012 and 1889
transcripts in the case of 2013. The distribution of the differentially expressed genes
(DEGs) in 2012 and 2013 are shown in the Figures 3C and 3D. Illustrated this way, it
was seen that the two subtropical sites bear quite different profiles in relative gene
expression, despite belonging to the same climate, as they are geographically adjacent.
In 2012, subtropical site B showed more up-regulated genes than down-regulated, both
pre- and post-chilling, by reference to the Mediterranean site N. In contrast, subtropical
site C showed more down-regulated than up-regulated genes both pre- and post-chilling
(Fig. 3C). Looking at the 2013 profiles, a reasonably consistent profile was seen for
subtropical site B, but subtropical site C bears a pattern that differs to 2012, albeit more
consistent with site B (Fig. 3D). Therefore, the difference in the number of differentially
expressed genes suggests that an unusual event influenced vine physiology in
subtropical site C in 2012 (Fig. 3C and 3D). This change in the gene expression profile
is likely to be a product of management interventions, as the sites were managed by
different farmers, e.g. chemical, fertilizer or irrigation strategies.
6.2. Transcriptional Bases for Bud Dormancy and Quiescent Differentiation
Between Climates.
The significant transcripts were grouped according to their developmental stages,
dormant buds (pre - chilling) and quiescent buds (post - chilling) and comparisons were
done between climates (Subtropical vs Mediterranean). Expression patterns following a
self-organizing map (SOM) analysis (Fig. 4 and Fig. 5). This clustering analysis
indicated a considerable influence of annual variation and crop management in the gene
expression of pre-chilling and post-chilling; although changes due to climate were also
evident. Functional enrichment analyses were performed on each of these clusters to
assess the biological significance underlying in each pattern.
6.2.1 Pre - chilling
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The Figure 4 summarizes six profiles product of the comparisons between climates in
2012 and 2013 in pre-chilling. There, it can be observed as SOM1, SOM4, SOM5 and
SOM6 are related to changes between years. In addition, SOM2 presents differences in
subtropical site C between 2012 and 2013 whereas subtropical site B showed the same
profile in both seasons; and only SOM3 reflects the same pattern in both locations of
subtropical climate against Mediterranean climate during the two seasons, although the
expression in Bumbak was higher than in Condo. SOM2 and SOM3 in pre-chilling had
the greatest number of genes, 523 and 526, respectively, while SOM5 and SOM6 in pre-
chilling had the lowest numbers among the clusters with 253 and 261, respectively.
The SOM3 (Pre) profile identified six functional categories that were induced in the
subtropical climate (Figure 4; SOM3). These categories were: ‘Diverse functions’,
‘Metabolism’, ‘Regulation overview’, ‘Response to stimulus’, ‘Signaling’ and
‘Transport overview’. Moreover, within ‘Metabolism’ genes related to three main
subcategories, ‘Cellular metabolism’, ‘Primary metabolism’, and ‘Secondary
metabolism’. The category of ‘Diverse functions’ included several genes coding for
NBS-LRR superfamily. Among them were genes encoding HcrVf1 protein
(VIT_01s0010g03210 and VIT_01s0010g03230), Disease resistance
(VIT_09s0054g00300 and VIT_16s0013g01700) and Leucine-rich repeat family
(VIT_09s0070g00690). These transcripts present a fold change >30-fold in subtropical
site B in 2012 (Figure 4; SOM3). The nucleotide binding site-leucine-rich repeat (NBS-
LRR) is a well-known class related with biotic stress leading pathogen resistance;
although recently it was also linked to light signals produced by neighbor plants. This
developmental strategy is known as shade-avoidance syndrome and caused acceleration
in stem growth and flowering as well as epinasty, as reported in the Arabidopsis
constitutive shade-avoidance1 (csa1) mutant (Faigón-Soverna et al., 2006). The csa1 is
a T-DNA mutant of a Toll/Interleukin1 (TIR) NBS-LRR gene (Faigón-Soverna et al.,
2006)
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Figure 4. Self-organization maps (SOMs) showing different patterns of gene expression during Pre-
chilling in two consecutive seasons. Letters B, C and N refer to the site of harvest, subtropical sites B and
C, and Mediterranean site N. A. Gene expression patterns are organized into SOMs (labeled as 1 to 6).
Comparisons were performed: B, C, and N against N. The number of Unigenes belonging to each SOM
category is indicated in parenthesis. Green represents down-regulated expression; magenta represents up-
regulated expression and black no changes in the expression, relative to site N. The brighter the color, the
larger the difference in gene expression. Functional annotation was assigned to the genes that had
matches to a putative molecular function. Enrichment analysis was carried out using FatiGO.
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In ‘Cellular metabolism’ two category were detected enriched the ‘Oxidation reduction’
and ‘Phytoalexin biosynthesis’ processes. Within ‘Oxidation reduction’, all transcripts
belonged to Cytochrome P450 oxidoreductase-family genes, including CYP82M1v3
(VIT_12s0035g00610), CYP89A6 (VIT_16s0039g00840), CYP714A1
(VIT_18s0089g00700) (Figure 4; SOM3). In plants, cytochrome P450 genes are
involved in biosynthetic and detoxification pathways. Cytochrome P450 genes are
involved in the phenylpropanoid biosynthetic pathway (lignins, antioxidants, flower
pigments, defense chemicals), fatty acids, hormones, and signaling molecules.
Additionally, Cytochrome P450 proteins participate in the breakdown of endogenous
compounds and toxic compounds encountered in the environment (Schuler et al 2003).
Furthermore, Cytochrome P450 has multiple functions under stress conditions and
multiple ways exist to regulate these functions in hypoxic tissues, and their differential
upregulation under hypoxia can indicate ROS production (Blokhina et al., 2010).
In the ‘Phytoalexin biosynthesis’ category, transcripts coding for Stilbene synthase gene
(STS) were found (VIT_10s0042g00870, VIT_16s0100g00830 and
VIT_16s0100g00940). A wide range of abiotic stress treatments lead to stilbene
biosynthesis, such as mechanical damage, exposure to UV-C light, treatment with
chemicals, such as aluminum ions, cyclodextrins, and ozone, and the application of
plant hormones like ethylene and jasmonates (Höll et al., 2013; Wang et al., 2010).
Moreover, a transcript coding for Resveratrol synthase (RS1) (VIT_16s0100g01110)
was found. The up-regulation of RS1 (VIT_16s0100g01110) was also reported in V.
riparia (Fennell et al., 2015) and Tempranillo (Díaz-Riquelme et al., 2012) during bud
dormancy. Additionally, a Stilbene synthase transcript was differential expressed in
poplar in the comparison of terminal bud and cambium tissue (Fennell et al., 2015).
Here, it was observed STSs and RS1 expressed in Mediterranean site N, but
comparatively more induced in both subtropical site B and C.
Amino sugar metabolism processes from ‘Primary metabolism’ presented several genes
related to Chitinase (VIT_05s0094g00320 and VIT_16s0050g02230) and Acidic
endochitinase (CHIB1) (VIT_15s0046g01570 and VIT_16s0050g02220). Chitinases in
plants play a main role in defence against pathogen attack, although, it has been
reported that chitinases are also involved in general stress, growth and development
processes (Kasprzewska et al., 2003).
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‘Phenylpropanoid metabolism’ was also altered in Lignin process (adj. P value 6.415E-
012), including sixteen Laccases, three of which were 70-fold induced in subtropical
site B in 2012 (VIT_00s1212g00020, VIT_18s0001g01280 and VIT_18s0075g00590).
Although the FC of these laccases values was comparatively less in 2013, they were still
higher than in subtropical site C. The laccases in plants have been reported to be
involved in varieties of biological processes such as wound healing, iron metabolism
and maintenance of cell wall structure and integrity. In addition, plant laccases have
been reported in responses to environmental stresses e.g. salinity and heavy metal stress
by lead (review by Wang et al., 2015). The marked signature of laccases in the pre-
chilling stage of subtropical site B suggested a high incidence of necrosis, particularly
in 2012.
In ‘Secondary metabolism’ category a prominent role for Stilbenoid biosynthesis was
indicated. This process included transcripts coding for Secoisolariciresinol
dehydrogenase (VIT_08s0007g02630), Cinnamoyl alcohol dehydrogenase
(VIT_13s0064g00270), Coniferyl-alcohol glucosyltransferase (VIT_18s0001g12040),
as well as, STR1 and STS genes that also are part of Phytoalexin pathway. This
indicates the induction of genes encoding several phenylpropanoid-related enzymes
controlling the key step for the synthesis of stilbene and lignin compounds.
Within the ‘Regulation overview’ category, the WRKY family transcription factor was
induced (SOM3, Pre). Six WRKY family members were differentially expressed;
WRKY DNA-binding protein 21 (VIT_00s2547g00010), 27 (VIT_02s0025g00420), 51
(VIT_04s0069g00970), 53 (VIT_16s0050g02510), 70 (VIT_13s0067g03140) and 75
(VIT_14s0068g01770). Several studies have implicated prominent roles of WRKY
factors in plant processes such as germination, senescence and responses to abiotic
stresses such as drought and cold (review by Rushton et al., 2010), as well as wounding
and salinity (review by Chen et al., 2012). Nevertheless, very little known about WRKY
TFs role in bud dormancy. Recently, several transcripts of grapevine VvWRKY TFs
were differentially expressed during the short-day induction of grapevine bud dormancy
(Fennell et al., 2015). Authors reported induction of a transcript coding for WRKY
DNA-binding protein 65 (VIT_10s0003g01600) during the perception phase, one
transcript during induction phase WRKY DNA-binding protein 71
(VIT_12s0028g00270) and three transcripts during dormancy maintenance, WRKY
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DNA-binding protein 48 (VIT_05s0077g00730), 65 (VIT_10s0003g01600) and 75
(VIT_01s0010g03930) (Fennell et al., 2015).
Within the ‘Response to stimulus’ category (SOM3, Pre), both abiotic (Oxidative stress
response) and biotic (Plant-pathogen interaction) stress were (P value 8.41E-8 and
2.45E-11, respectively). Many genes were altered in ‘Oxidative stress response’
process, among them were six Glutathione S-transferases, such Glutathione S-
transferase 8 GSTU8 (VIT_06s0004g05700), 10 GSTU10 (VIT_01s0026g02400), 22
GSTU22 (VIT_19s0093g00110), 25 GSTU7 (VIT_07s0005g04880 and
VIT_08s0040g00920) and 25 GSTU25 (VIT_19s0093g00320). Additionally, transcripts
coding for Lactoylglutathione lyase (VIT_11s0016g05010), L-ascorbate oxidase
(VIT_07s0031g01010) Peroxidase (VIT_08s0058g00990) along with Laccases were
detected. All these genes are directly related to ROS including to cytochrome P450
family proteins, they are involved both in H2O2 elimination and detoxification
(Blokhina et al., 2010).
Several transcripts of biotic stress were found induced in ‘Plant-pathogen interaction’
process coding for R protein disease resistance protein (VIT_10s0071g00150), R
protein L6 (VIT_18s0041g00190), R protein MLA10 (VIT_00s0144g00120) and R
protein PRF disease resistance protein (VIT_03s0017g00920). The hypersensitive
response (HR) is a form of cell death often associated with plant resistance to pathogen
infection. It is a multicomponent response involving increased expression of defence-
associated genes (pathogenesis-related or PR genes) and a form of localised cell death
(LCD) at the site of infection to restrict the advance of microorganisms. Although the
HR has been widely reported during biotic interactions, some of its features, including
LCD and induction of PR genes, are shared by plant responses to a number of abiotic
stresses such as excess of excitation energy (EEE), and exposure to ozone (Review by
Zurbriggen et al., 2010). Additionally, Morel et al., (1997) reported that phytoalexins
and pathogenesis related (PR) proteins are also induced by abiotic treatments and
physical stresses. Hence the signature of PR proteins is in agreement with the necrotic
symptoms that present the buds.
In the category of ‘Hormone Signaling’, Jasmonate Signaling and Salicylic acid-
responsive genes were altered (SOM3, Pre). These two pathways share these genes, the
transcripts found were, Enhanced disease susceptibility 1 (EDS1)
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(VIT_17s0000g07420), Pathogenesis related protein 1 precursor (pr1 gene)
(VIT_03s0088g00700) and Pathogenesis-related protein 1 precursor (PRP 1)
(VIT_03s0088g00810 and VIT_03s0088g00710). Ochsenbein et al., (2006) have
reported that EDS1 gene plays an important role during oxidative stress caused by the
release of singlet oxygen and previously was also reposted in the processing of
hydrogen peroxide/superoxide-derived signals (Mateo et al., 2004). Likewise,
Pathogenesis-related proteins have also been reported in abiotic stresses (Przymusiński
et al., 2004).
Protein kinase, in ‘Signaling pathway’, had the most significant adj. P value
(6.09E-038) in the FatiGo analysis. Here, 110 transcripts in the SOM3 cluster (Pre)
were altered. A selection of transcripts had a 3-fold FC in both seasons in subtropical
sites B and C; Clavata1 receptor kinase (CLV1; VIT_04s0008g00300), Receptor kinase
homolog LRK10 (VIT_16s0050g02700), Receptor kinase (TRKe;
VIT_11s0052g01460), S-receptor protein kinase (VIT_17s0053g00400) and Wall-
associated kinase 2 (WAK2) (VIT_17s0000g04420). The CLV1 gene encodes a
putative receptor kinase required for the proper balance between cell proliferation and
differentiation in Arabidopsis shoots and flower meristems (Stone et al., 1998). CLV1
has been postulated to either inhibit proliferation of undifferentiated cells at the
meristem or promote the transition of these cells toward differentiation (Stone et al.,
1998).
In ‘Transport overview’ category Oxidase-dep Fe2+
Transport process (Figure 4; SOM3)
was indicated, which included transcripts coding for Laccase (VIT_00s1212g00020,
VIT_18s0001g01280 and VIT_18s0075g00590) and L-ascorbate oxidase
(VIT_07s0031g01010). Laccases and ascorbate oxidase belong to blue oxidases, they
are multi-copper enzymes. They can be classified by their substrate specificity; for
example, ascorbate oxidases oxidize ascorbate, and laccases oxidize aromatic substrates
such as diphenols (Hoegger et al., 2006). McCaig et al., (2005) reported a classification
of plant Laccase-like multicopper oxidase (LMCO) providing evidence that most
LMCOs from A. thaliana may play a role in iron or other metal metabolisms.
6.2.2. Post - chilling
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19
Seven SOMs were defined in the post-chilling cluster analysis from the comparisons of
the two subtropical sites B and C against the Mediterranean site N in 2012 and 2013
(Figure 5). SOM2 showed the highest numbers of genes (415), while SOM1 and SOM5
had the least, 181 and 191 transcripts on them, respectively. The profiles of SOM2,
SOM3 and SOM7 indicate differential regulation between the two seasons considered.
In addition, SOM4 indicates differential regulation in subtropical site C between 2012
and 2013; relative repression versus induction, respectively, while these genes were
induced in both seasons in subtropical site B. Moreover, SOM1 and SOM6 indicated
differences in magnitude of change between seasons; genes of SOM1 were more
repressed in 2012 than in 2013, those of SOM6 were more induced in subtropical site B
in 2012, relative to 2013, although subtropical site C was reasonably consistent. By
contrast, genes of SOM5 showed consistent profiles between seasons, and relative
consistency between sites.
In SOM1 (post-chilling) one functional category was found, ‘Regulation overview’,
corresponding to C2C2-YABBY family transcription factors. Also, in SOM5 (Post),
genes of the ‘Signaling’ category related to Protein kinases and the Ethylene-mediated
Signaling pathway. Functional analysis in SOM6 (post-chilling) highlighted enrichment
of five functional categories; ‘Diverse functions’, ‘Metabolism (Secondary
metabolism)’, ‘Response to Stimulus’, ‘Signaling’, and ‘Transport Overview’.
The C2C2-YABBY family transcription factor of the ‘Regulation overview’ category
obtained a significant adj. P value (1.44E-03; Figure 5 SOM1). Three transcripts were
found coding for Axial regulator YABBY TFs; the Axial regulator YABBY1 (also
called Abnormal floral organs or Protein FILAMENTOUS FLOWER (FIL))
(VIT_15s0048g00550), YABBY2 (VIT_08s0032g01110) and YABBY5
(VIT_11s0016g05590). These genes were relatively repressed in both subtropical sites,
compared to the Mediterranean site, in both seasons at the post-chilling stage. The
magnitude of repression was greater in 2012, most markedly for subtropical site B.
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20
Figure 5. Self-organization maps (SOMs) showing different patterns of gene expression during post-
chilling in two consecutive seasons. Letters B, C and N refer to the site of harvest, subtropical sites B and
C, and Mediterranean site N. A. Gene expression patterns are organized into SOMs (labeled as 1 to 7).
Comparisons were performed: B, C, and N against N. The number of Unigenes belonging to each SOM
category is indicated in parenthesis. Green represents down-regulated expression; magenta represents up-
regulated expression and black no changes in the expression, relative to site N The brighter the color, the
larger the difference in gene expression. Functional annotation was assigned to the genes that had
matches to a putative molecular function. Enrichment analysis was carried out using FatiGO.
The YABBY (YAB) family of TFs participates in a diverse range of processes that
include leaf and floral patterning, organ growth, and the control of shoot apical
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21
meristem organization and activity. Siegfried et al., (1999) described that three members
of YABBY (FIL, YAB2 and YAB3) were expressed in abaxial domains of all above-
ground lateral organ primordia (except the ovules) and act to specify abaxial cell fate in
lateral organs. Also, authors hypothesized that the loss of polar expression results in loss
of polar differentiation of lateral organs. YABBY2 gene appears to have conserved
roles in specifying abaxial cell fate in leaves, floral organs and ovules. It is expressed in
a polar manner in all lateral organs produced by the apical and flower meristems
(Bowman et al., 2000). Additionally, YABBY2 and YABBY5 genes are expressed in
leaves and have been termed 'vegetative YABBYs'.
In SOM5 (post-chilling) two processes altered in the category of ‘Signaling’ were
indicated; Protein kinase (1,15E-04) and Ethylene-mediated Signaling pathway (7,68E-
03). This cluster grouped genes that were relatively induced in both subtropical sites in
both years, by comparison to the Mediterranean site N (Figure 5; SOM5).
Within this cluster, 28 transcripts that coded for several genes of Protein kinases were
found. Among them were, Calcium-dependent protein kinase (VIT_17s0053g00710),
FRK1 (FLG22-induced receptor-like kinase 1, also known as Senescence-induced
receptor-like serine/threonine-protein kinase) (VIT_07s0005g06500), Protein kinase
family (VIT_07s0129g00880), Receptor serine/threonine kinase (VIT_16s0148g00300),
S-locus lectin protein kinase (VIT_00s0420g00010), Wall-associated kinase 3 (WAK3)
(VIT_10s0003g05160) and Wall-associated receptor kinase 5 (VIT_10s0003g05130).
Calcium-dependent protein kinases (CDPKs) have been implicated in perceiving
intracellular changes in Ca2+
concentration and translating them into specific
phosphorylation events to initiate further downstream signaling processes. They have
been mainly characterized in rapid abiotic stress and immune signaling response and
less extended in long-term adaptive processes or plant development (Schulz et al.,
2013). CDPKs are positive regulator of abiotic stress responses and their induction in
plants can enhances stress tolerance, they have been reported in abiotic stress stimuli in
the context of salinity, drought, and cold; in particular, isoforms were implicated in
ABA-mediated signaling (Schulz et al., 2013). Likewise, CDPKs participate in the
translation of pathogen signal-induced changes in the Ca2+
concentration into plant
defense reactions. Among the reactions reported are ROS synthesis, changes in
phytohormone synthesis and signaling, and cell death (Schulz et al., 2013). However,
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22
their activation by pathogen stress and subsequent deactivation in the early stage of
infection, suggests a role for CDPKs in the onset of plant immune reactions death
(Schulz et al., 2013).
In Glycine max was demonstrated that Senescence-Associated Receptor-Like Kinase
(GmSARK) plays an important role in the regulation of soybean leaf senescence (Li et
al., 2006). It was also suggested that two SARK genes regulate leaf senescence through
synergistic actions of auxin and ethylene and that the SARK-mediated pathway may be
a widespread mechanism in regulating leaf senescence (Xu et al., 2011). Moreover,
evidence is emerging that WAKs serve as pectin receptors during pathogen exposure or
wounding and cell expansion during plant development (Kohorn et al., 2012). Wak3
and Wak5 have been reported to be expressed primarily in leaves and stems of
Arabidopsis; also they both can be greatly induced by salicylic acid or INA (2,2-
dichloroisonicotinic acid), the SA analog ( He et al., 1999).
In the Ethylene-mediated Signaling pathway, several transcripts within SOM5 were
identified (Figure 5), coding for 1-aminocyclopropane-1-carboxylate oxidase (ACO)
(VIT_00s2086g00010 and VIT_03s0091g01080), Ethylene-responsive transcription
factor ERF105 (VIT_16s0013g00900 and VIT_16s0013g01070), Ethylene-responsive
transcription factor related to APETALA2 11 (VIT_08s0007g07250), among others.
Ethylene is a hormone involved in numerous aspects of growth, development, and
responses to biotic and abiotic stresses in plants. ACC oxidase (ACO) is involved in the
final step of ethylene production in plant tissues (Ruduś et al., 2013). Also, Chao et al.,
(2013) reported an increase in ACO levels and activities during paradormancy release of
leafy spurge (Euphorbia esula) buds. On the other hand, ERF105 and Ethylene-
responsive transcription factor related to APETALA2 11 belong to the AP2/ERF
family. They have been reported likely to regulate the developmental, physiological and
biochemical responses of plants to a variety of environmental stress conditions,
including those occurring in combination with other abiotic and biotic stresses (Mizoia
et al., 2012; Mishra et al., 2015).
6.3. Finding potential biomarkers
The next step was looking for potential candidate genes that could be used as
biomarkers, to identify the gene profiles in each stage and thus to help to make better
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23
decisions related with the crop management. For this, it was selected the genes that
presented the same profile (up- and down-regulated) during each stage of dormancy.
The Venn diagram that is represented in the Figure 6, summarize the up-regulated and
down-regulated genes during the two consecutive years in pre and post chilling, they
were product of the comparison between Subtropical climate, places B and C, against
Mediterranean climate, place N. From the 2238 transcripts that were differentially
expressed in pre-chilling just 37 presented the same profiles, 32 transcripts up-regulated
and 5 down-regulated. Whereas in post-chilling just 60 transcripts from the 1889 that
were differentially expressed, 50 up-regulated and 10 down-regulated.
Figure 6. Venn diagrams and functional analysis of differentially expressed genes (1% FDR in limma
and ≥3-fold change). A. and B. Venn diagram of transcripts DEGs during pre-chilling (right) and post-
chilling (left), respectively, in 2012 and 2013 seasons. Green represents down-regulated genes and
magenta represents up-regulated genes. Comparisons were performed: B, C, and N against N. Summary
of functional categories significantly enriched (5% FDR in a Fisher’s exact test) within up- and
downregulated transcripts in each developmental stage.
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24
Following a functional enrichment analysis was performed to each core set of genes
with the same profile found in pre- and post-chilling (FatiGO, P=0.05). Pre-chilling was
enriched in the ‘Signaling’ category in the Protein kinases process, 10 transcripts coding
to Clavata1 receptor kinase (CLV1; VIT_04s0008g00300), Receptor kinase homolog
LRK10 (VIT_16s0050g02700), Receptor kinase (TRKe; VIT_11s0052g01460), S-
receptor protein kinase (VIT_17s0053g00400) and Wall-associated kinase 2 (WAK2)
(VIT_17s0000g04420) were found among others. CLV1, LRK10 and WAK2 are
members of Plant receptor-like kinases (RLK) family and have been related with plant-
microbe interaction and stress responses (Shui and Bleecker, 2001).
In post-chilling, 20 transcripts were detected coding for genes that belong to ‘Signaling’
category (Figure 6). Among them are Calcium-dependent protein kinase
(VIT_17s0053g00710), CLL1B clavata1-like receptor S/T protein kinase
(VIT_16s0013g01990), FRK1 (FLG22-induced receptor-like kinase 1)
(VIT_07s0005g06500), S-locus lectin protein kinase (VIT_00s0420g00010), Wall-
associated kinase 3 (WAK3; VIT_10s0003g05160), Wall-associated receptor kinase 5
(VIT_10s0003g05130), 1-aminocyclopropane-1-carboxylate oxidase (ACO;
VIT_03s0091g01080), Ethylene-responsive transcription factor (ERF105;
VIT_16s0013g00900), Ethylene-responsive transcription factor related to APETALA2
11 (VIT_08s0007g07250). Here, genes belong to Protein Kinases process along with
Ethylene-mediated Signaling pathway were also identified.
The genes, that presented the same profile during two consecutive years in the
comparison Subtropical vs Mediterranean climates, could be used as potential
biomarker for anticipate actions.
Finally, in the Figure 7 are shown the 97 genes that presented the same profile during
pre- and post-chilling (37 and 60, respectively). Within this core set of genes, 3 genes
were differentially expressed in both, pre- and post-chilling. Two genes were up-
regulated, Ovate family protein 12 OFP12 (VIT_05s0020g03520) and EREBP-4
(VIT_09s0002g08960); while one was down-regulated, it was Gibberellin –regulated
protein (GASA1; VIT_18s0001g14270).
The OVATE gene was first identified as an important regulator of fruit shape in tomato.
Ovate Protein Family genes (OFPs) were also characterized in Arabidopsis (AtOFPs)
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25
and demonstrated to regulate plant growth and development (Hackbusch et al., 2005; Li
et al., 2011; Wang et al., 2011). Over-expression of OVATE reduces the size of floral
organs and leaflets; therefore, OVATE is considered to be a negative regulator of plant
growth (Liu et al., 2002). Therefore, this data suggests that analyzing the gene
expression profile of the transcript that encoded OFP12 (VIT_05s0020g03520) is a
good candidate to evaluate the stage of buds during pre- and post-chilling.
Figure 7. Expression profile of genes with 1% FDR and FC => |3-fold| during pre-chilling and post-
chilling in the comparisons B vs N and C vs N in 2012 and 2013 from Figure 6. Fold change (FC) is
display as green to down-regulated expression; magenta to up-regulated expression and gray to not
expression. Different colors represent the functional categories.
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26
CONCLUSIONS
In the present work, differential expression analysis and functional enrichment of
RNAseq data identified numerous transcripts associated with necrosis within the buds
from subtropical sites, which was not visibly detectable during sampling.
Notwithstanding this dominating feature, this stringent statistical comparison identified
three genes, which were differentially expressed in all subtropical conditions relative to
the Mediterranean site, that relate to meristem function and fate, and may thus be useful
markers of the disorderly regulation of vine physiology in subtropical climates.
Further dissecting the pre-chilling and post-chilling conditions of both years considered,
markers unique to these developmental states in the subtropical sites were also
identified. In the pre-chilling condition, genes relating to phytoalexin, phenylpropanoid
and lignin synthesis were prominent, as well as more general reponses to abiotic
(oxidative stress response) and biotic stresses (plant-pathogen interaction). Whether
these signatures were indicative of the climate differences cannot be concluded from
this study, due to the necrosis identified.
Post-chilling data also indicated genes related with biotic and abiotic stresses. However,
genes encoding the YABBY family of transcription factors are highly likely to relate to
bud development, due to their known role in specifying abaxial cell fate in other plant
species. YABBY transcrips were down-regulated in the subtropical sites relative to the
Mediterranean site in both years considered, suggesting that while bud meristems in
Mediterranean climate are beginning to develop and activate cell proliferation, buds in
the subtropical sites are not coordinated regulated.
From the 97 transcripts that presented the same profile during pre- and post-chilling, 37
and 60 respectively, 3 genes were found in both stages. In particular, a gene encoding an
Ovate family protein 12 OFP12 (VIT_05s0020g03520), which was upregulated 14-fold
is prominent, as it has been previously been reported to be a negative regulator of plant
growth. Therefore, this data strongly suggests OFP12 is a potential biomarker to
anticipate measures in grapevine management in subtropical climate.
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27
BIBLIOGRAPHY
1. Ali, K, Maltese, F, Choi, YH. and Verpoorte, R. (2010) Metabolic constituents
of grapevine and grape-derived products. Phytochem. Rev. 9, 357e378.
2. Al-Shahrour F, Diaz-Uriarte R. and Dopazo J. (2004) FatiGO: a web tool for
finding significant associations of Gene Ontology terms with groups of
genes. Bioinformatics. 20:578–580.
3. Barakat A,, Szick-Miranda K, Chang IF, Guyot R, Blanc G, Cooke R,Delseny
M. and Bailey-Serres J. (2001) The Organization of Cytoplasmic Ribosomal
Protein Genes in the Arabidopsis Genome. Plant Physiology. 127(2):398-415.
4. Blokhina O. and Fagerstedt KV. (2010) Oxidative metabolism, ROS and NO
under oxygen deprivation. Plant Physiol Biochem. 48(5):359-73.
5. Bowman JL. (2000) Axial patterning in leaves and other lateral organs. Curr
Opin Genet Dev. 10(4):399-404.
6. Chao WS, Serpe M, Suttle JC. and Jia Y. (2013) Increase in ACC oxidase
levels and activities during paradormancy release of leafy spurge
(Euphorbia esula) buds. Planta. 238(1):205-15.
7. Chen L, Song Y, Li S, Zhang L, Zou C. and Yu D. (2012) The role of WRKY
transcription factors in plant abiotic stresses. Biochim Biophys Acta.
1819(2):120-8.
8. Faigón-Soverna A, Harmon FG, Storani L, Karayekov E, Staneloni RJ;
Gassmann W- Más P, Casal JJ, Kay SA. and Yanovskya MJ. (2006) A
Constitutive Shade-Avoidance Mutant Implicates TIR-NBS-LRR Proteins
in Arabidopsis Photomorphogenic Development. Plant Cell. 18(11):2919–
2928.
9. Fennell AY, Schlauch KA, Gouthu S, Deluc LG, Khadka V, Sreekantan L,
Grimplet J, Cramer GR. and Mathiason KL. (2015) Short day transcriptomic
º
28
programming during induction of dormancy in grapevine. Front Plant Sci.
4(6):834.
10. Grimplet J, Van Hemert J, Carbonell-Bejerano P, Díaz-Riquelme J, Dickerson J,
Fennell A, Pezzotti M. and Martínez-Zapater JM. (2012). Comparative
analysis of grapevine whole-genome gene predictions, functional
annotation, categorization and integration of the predicted gene sequences.
BMC Research Notes. 5, 213.
11. Hackbusch J, Richter K, Müller J, Salamini F. and Uhrig JF. (2005) A central
role of Arabidopsis thaliana ovate family proteins in networking and
subcellular localization of 3-aa loop extension homeodomain proteins. Proc.
Natl. Acad. Sci. U.S.A. 102: 4908–4912
12. He ZH, Cheeseman I, He D. and Kohorn BD. (1999) A cluster of five cell wall-
associated receptor kinase genes, Wak1-5, are expressed in specific organs
of Arabidopsis. Plant Mol. Biol. 39(6):1189-96.
13. Hoegger PJ, Kilaru S, James TY, Thacker JR. and Kües U. (2006) Phylogenetic
comparison and classification of laccase and related multicopper oxidase
protein sequences. FEBS J. 273(10):2308-26.
14. Höll J, Vannozzi A, Czemmel S, D’Onofrio C, Walker AR, Rausch T, Lucchin
M, Boss PK, Dry IB. and Bogs J. (2013) The R2R3-MYB Transcription
Factors MYB14 and MYB15 Regulate Stilbene Biosynthesis in Vitis
vinifera. The Plant Cell. 25:4135–4149.
15. Jaillon O, Aury JM, Noel B, Policriti A, Clepet C, Casagrande A, Choisne N,
Aubourg S, Vitulo N, Jubin C, Vezzi A, Legeai F, Hugueney P, Dasilva C,
Horner D, Mica E, Jublot D, Poulain J, Bruyère C, Billault A, Segurens B,
Gouyvenoux M, Ugarte E, Cattonaro F, Anthouard V, Vico V, Del Fabbro C,
Alaux M, Di Gaspero G, Dumas V, Felice N, Paillard S, Juman I, Moroldo M,
Scalabrin S, Canaguier A, Le Clainche I, Malacrida G, Durand E, Pesole G,
Laucou V, Chatelet P, Merdinoglu D, Delledonne M, Pezzotti M, Lecharny A,
Scarpelli C, Artiguenave F, Pè ME, Valle G, Morgante M, Caboche M, Adam-
Blondon AF, Weissenbach J, Quétier F, Wincker P. and French-Italian Public
º
29
Consortium for Grapevine Genome Characterization. (2007) The grapevine
genome sequence suggests ancestral hexaploidization in major angiosperm
phyla. Nature. 449(7161):463-7.
16. Kasprzewska A. (2003) Plant chitinases-regulation and function. Cell Mol
Biol Lett. 8(3):809-24.
17. Kohorn BD. and Kohorn SL. (2012) The cell wall-associated kinases, WAKs,
as pectin receptors. Front Plant Sci. 8;3:88.
18. Lavee S. and May P. (1997) Dormancy of grapevine buds - facts and
speculation. Aust J Grape Wine Res. 3(1):31–46.
19. Lebon G, Duchêne E, Brun O. and Clément C. (2005) Phenology of flowering
and starch accumulation in grape (Vitis vinifera L.) cuttings and vines. Ann
Bot. 95(6):943-8.
20. Li XP, Gan R, Li PL, Ma YY, Zhang LW, Zhang R, Wang Y. and Wang NN.
(2006) Identification and functional characterization of a leucine-rich
repeat receptor-like kinase gene that is involved in regulation of soybean
leaf senescence. Plant Mol. Biol. 61: 829–844
21. Liu J, Van Eck J, Cong B, and Tanksley SD. (2002) A new class of regulatory
genes underlying the cause of pear-shaped tomato fruit. Proc. Natl. Acad.
Sci. U.S.A. 99(20):13302-6.
22. Mateo A, Mühlenbock P, Rustérucci C, Chang CC, Miszalski Z, Karpinska B,
Parker JE, Mullineaux PM. and Karpinski S. (2004) Lesion simulating disease1
is required for acclimation to conditions that promote excess excitation
energy. Plant Physiol. 136(1):2818-30.
23. Mathiason K, He D, Grimplet J, Venkateswari J, Galbraith DW, Or E. and
Fennell A. (2009) A. Transcript profiling in Vitis riparia during chilling
requirement fulfillment reveals coordination of gene expression patterns
with optimized bud break. Funct Integr Genomics. 9(1):81-96.
º
30
24. McCaig BC, Meagher RB. and Dean JFD. (2005) Gene structure and
molecular analysis of the laccase-like multicopper oxidase (LMCO) gene
family in Arabidopsis thaliana. Planta. 221(5):619-36
25. Mishra S, Phukan UJ, Tripathi V, Singh DK, Luqman S. and Shukla RK. (2015)
PsAP2 an AP2/ERF family transcription factor from Papaver somniferum
enhances abiotic and biotic stress tolerance in transgenic tobacco. Plant
Mol. Biol. 89(1-2):173-86.
26. Mizoia J, Shinozakib K. and Yamaguchi-Shinozaki K. (2012) AP2/ERF family
transcription factors in plant abiotic stress responses. Biochim. Biophys.
Acta. 1819(2):86-96.
27. Morel JB. and Dangl JL. (1997) The hypersensitive response and the
induction of cell death in plants. Cell Death Differ. 4(8):671-83.
28. N. Bray, H. Pimentel, P. Melsted and L. Pachter, Near-optimal RNA-Seq
quantification with kallisto to the arXiv. http://pachterlab.github.io/kallisto/
29. Ochsenbein C, Przybyla D, Danon A, Landgraf F, Göbel C, Imboden A,
Feussner I. and Apel K. (2006) The role of EDS1 (enhanced disease
susceptibility) during singlet oxygen-mediated stress responses of
Arabidopsis. Plant J. 47(3):445-56.
30. Possingham, JV. (2004) On The Growing Of Grapevines In The Tropics
ISHS Acta Horticulturae 662: VII International Symposium on Temperate Zone
Fruits in the Tropics and Subtropics. Acta Hortic. 662: 39-44.
31. Przymusiński R, Rucińska R. and Gwóźdź EA. (2004) Increased accumulation
of pathogenesis-related proteins in response of lupine roots to various
abiotic stresses. Environ. Exp. Bot. 52(1):53–61.
32. Ritchie ME, Phipson B, Wu D, Hu Y, Law CW, Shi W. and Smyth GK. (2015)
limma powers differential expression analyses for RNA-sequencing and
microarray studies. Nucleic Acids Research, 43(7):e47.
º
31
33. Robinson MD, McCarthy DJ. and Smyth GK. (2010) edgeR: a Bioconductor
package for differential expression analysis of digital gene expression data.
Bioinformatics. 26(1):139-40
34. Ruduś I, Sasiak M. and Kępczyński J. (2013) Regulation of ethylene
biosynthesis at the level of 1-aminocyclopropane-1-carboxylate oxidase
(ACO) gene. Acta Physiol. Plant. 35:295–307.
35. Rushton PJ, Somssich IE, Ringler P. and Shen QJ. (2010) WRKY transcription
factors. Trends Plant Sci. 15(5):247–258.
36. Schuler MA. and Werck-Reichhart D. (2003) Functional Genomics Of P450s.
Annu. Rev. Plant Biol. 54:629–67.
37. Schulz P, Herde M. and Romeis T. (2013) Calcium-dependent protein
kinases: hubs in plant stress signaling and development. Plant Physiol.
163(2):523-30.
38. Shiu SH and Bleecker AB. (2001) Plant receptor-like kinase gene family:
diversity, function, and signaling. Sci STKE. 2001(113):re22.
39. Siegfried KR, Eshed Y, Baum SF, Otsuga D, Drews GN. and Bowman JL.
(1999) Members of the YABBY gene family specify abaxial cell fate in
Arabidopsis. Development. 126(18):4117-28.
40. Stone JM, Trotochaud AE, Walker JC. and Clark SE. (1998) Control of
Meristem Development by CLAVATA1 Receptor Kinase and Kinase-
Associated Protein Phosphatase Interactions. Plant Physiol. 117(4):1217–
1225.
41. Wang J, Feng J, Jia W, Chang S, Li S. and Li Y. (2015) Lignin engineering
through laccase modification: a promising field for energy plant
improvement. Biotechnol Biofuels. 8:145.
42. Wang S, Chang Y, Guo J, Zeng Q, Ellis BE. and Chen JG. (2011) Arabidopsis
ovate family proteins, a novel transcriptional repressor family, control
multiple aspects of plant growth and development. PLoS One. 6(8):e23896.
º
32
43. Wang W, Tang K, Yang HR, Wen PF, Zhang P, Wang HL. and Huang WD.
(2010) Distribution of resveratrol and stilbene synthase in young grape
plants (Vitis vinifera L. cv. Cabernet Sauvignon) and the effect of UV-C on its
accumulation. Plant Physiol Biochem. 48(2-3):142-52.
44. Xu F, Meng T, Li P, Yu Y, Cui Y, Wang Y, Gong Q. and Wang NN. (2011) A
soybean dual-specificity kinase, GmSARK, and its Arabidopsis homolog,
AtSARK, regulate leaf senescence through synergistic actions of auxin and
ethylene. Plant Physiol. 157(4):2131-53.
45. Zurbriggen MD, Carrillo N. and Hajirezaei MR. (2010) ROS signaling in the
hypersensitive response When, where and what for? Plant Signal Behav.
5(4): 393–396.
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9. ANEXOS
9.1. FastQC command line
for i in {1..n}
do
fastqc -t 4 <path to fastq file>/"$i"*.fastq.gz --outdir=<path to output
folder>/fastqc_reports
done
9.2. Trimmomatic command line
for i in {1..n}
do
java -jar <path of the program>/Trimmomatic-0.33/trimmomatic-0.33.jar SE -threads 4
-phred33 -trimlog <path of a folder to save the files>/trimmed_reads/trimlog_"$i" /dd_
<path to fastq file>/"$/Sample_"$i"/"$i"*.fastq.gz <path to save fastq
file>/"$/Sample_"$i"_trimmed.fastq.gz
ILLUMINACLIP:/usr/local/packages/Trimmomatic-0.33/adapters/TruSeq3-
SE.fa:2:30:10 LEADING:20 TRAILING:20 SLIDINGWINDOW:4:20 MINLEN:25
done
9.3. Kallisto on hiseq command line
# 1st make index file
/usr/local/packages/kallisto/build/bin/kallisto index -i Vitis.idx
/dd_groupdata/Vitis.fa
# run quant
for i in {1..n}
do
<path of the program>/kallisto quant -i <path of the index>/Vitis.idx -o =<path
to output folder>/kallisto_out/sample_"$i" --single -l 270 <path to fastq
file>/Sample_"$i"_trimmed.fastq.gz
done