Chapter 13 Differential Gene Expression &

plant development

Regulation of gene expression

Environmental stimuli Hormones Transcription factors microRNAs

Arabidopsis

MicroRNAs

Overexpression of miR156

microRNAs and RNAi RNAi – RNA interference

– Used to determine the consequences of down-regulating gene expression

Technologies used in gene identification

RNAi Mutational studies Transposon tagging Microarray analysis

Arabidopsis

Transposable elements

Transposable elements

AC and DS in maize– AC encodes transposase,

required to excise DS

Transposon tagging

Transposon tagging utilizes colorimetric expression assays

GUS reporter gene (B-glucuronidase), E. coli

GFP (green fluorescent protein), jellyfish

DNA microarrays Can accommodate ~20,000 genes

Microarrays and development

Example– Vegetative meristem

mRNA labeled green– Flower bud mRNA

labeled red

The discovery of microRNAs has resulted in which gene

analysis technology?

1. RNAi2. Chemical mutagenesis3. Transposon tagging4. Microarray analysis

GUS and GFP reporter genes are utilized in

1. RNAi2. Chemical mutagenesis3. Transposon tagging4. Microarray analysis

Comparing gene expression under two different conditions is best

accomplished using

1. RNAi2. Chemical mutagenesis3. Transposon tagging4. Microarray analysis

Determining which tissues a gene is expressed in can be

examined using

1. RNAi2. Chemical mutagenesis3. Transposon tagging4. Microarray analysis5. More than one of the above