NCBI Quick Overview of Bioinformatics Chuong Huynh NIH/NLM/NCBI New Delhi, India September 28, 2004...
-
Upload
maud-lucas -
Category
Documents
-
view
220 -
download
0
Transcript of NCBI Quick Overview of Bioinformatics Chuong Huynh NIH/NLM/NCBI New Delhi, India September 28, 2004...
NC
BI
Quick Overview of Bioinformatics
Chuong HuynhNIH/NLM/NCBI
New Delhi, IndiaSeptember 28, [email protected].
gov
NC
BI
What is bioinformatics? - Definition
• My definition – bringing biological themes to computers
• Peter Elkin: Primer on Medical Genomics: Part V: Bioinformatics– “Bioinformatics is the discipline that develops and applies
informatics to the field of molecular biology.”• BISTIC Bioinformatics Definition
– “Research, development, or application of computational tools and approaches for expanding the use of biological, medical, behavioral or health data, including those to acquire, store, organize, archive, analyze, or visualize such data”
• BISTIC Computational Biology Definition– “Computational Biology: the development and application
of data-analytical and theoretical methods, mathematical modeling and computational simulation techniques to the study of biological, behavioral, and social systems.”
• http://www.bisti.nih.gov/
NC
BI
Useful/Necessary Bioinformatics Skills
• Strong background in some aspect of molecular biology!!! • Ability to communicate biological questions
comprehensibly to computer scientists• Thorough comprehension of the problem in the
bioinformatics field• Statistics (association studies, clustering, sampling)• Ability to filter, parse, and munge data and
determine the relationships between the data sets• Mathematics (e.g. algorithm development)• Engineering (e.g. robotics)• Good knowledge of a few molecular biology software
packages (molecular modeling / sequence analysis)• Command line computing environment (Linux/Unix
knowledge)• Data administration (esp. relational database concept) and
Computer Programming Skills/Experience (C/C++, Sybase, Java, Oracle) and Scripting Language Knowledge (Perl and perhaps Phython)
NC
BI
Bioinformatics Flow Chart (0)
6. Gene & Protein expression data
7. Drug screening
Ab initio drug design ORDrug compound screening in database of molecules
8. Genetic variability
1a. Sequencing
1b. Analysis of nucleic acid seq.
2. Analysis of protein seq.
3. Molecular structure prediction
4. molecular interaction
5. Metabolic and regulatory networks
NC
BI
Bioinformatics Flow Chart (1)
1a. Sequencing
1b. Analysis of nucleic acid seq.
-Base calling-Physical mapping-Fragment assembly
-gene finding-Multiple seq alignment evolutionary tree
Stretch of DNA coding for protein;Analysis of noncoding region of genome
2. Analysis of protein seq.
3. Molecular structure prediction 3D modeling;DNA, RNA, protein, lipid/carbohydrate
Sequence relationship
4. molecular interactionProtein-protein interactionProtein-ligand interaction
5. Metabolic and regulatory networks
NC
BI
Bioinformatics Flow Chart (2)
6. Gene & Protein expression data
7. Drug screening
-EST-DNA chip/microarray
a) Lead compound binds tightly to binding site of target proteinb) Lead optimization – lead compound modified to be nontoxic, few side effects, target deliverable
Ab initio drug design ORDrug compound screening in database of molecules
8. Genetic variability
Drug molecules designed to be complementary to bindingSites with physiochemical and steric restrictions.
-Now investigated at the genome scale
-SNP, SAGE
NC
BI
Genome Sequencing
Libraries
Sequencing
Release
Assembly
Annotation
Closure
Strategy
•Most genome will be sequenced and can be sequenced;
few problem are unsolvable.
Clone by clone vs whole genome shotgun
•Problem lies in understanding what you have:
•Gene prediction/gene finding
•Annotation
Subcloning; generate small insert libraries
Assembly: Process of taking raw single-pass reads into contiguous consensus sequence (Phred/Phrap)
Assembly
Libraries
Strategy
Sequencing
Closure: Process of ordering and merging consensus sequences into a single contiguous sequence
Closure
Annotation -DNA features (repeats/similarities)-Gene finding-Peptide features-Initial role assignment-Others- regulatory regions
Release Release data to the public e.g. EMBL or GenBank
NC
BI
Complete sequence
Shotgun reads
Contigs
Genomic DNA
Shearing/Sonication
Subclone and Sequence
Assembly
Finishing
Finishing read
Sequencing
Small DNA fragments1.0-2.0kb
Clone LibrarypUC18
DNA sequencingRandom clones
Both strands coverage;Gap filled
NC
BI
Annotation of eukaryotic genomes
transcription
RNA processing
translation
AAAAAAA
Genomic DNA
Unprocessed RNA
Mature mRNA
Nascent polypeptide
folding
Reactant A Product BFunction
Active enzyme
ab initio gene prediction
Comparative gene prediction
Functional identification
Gm3
NC
BI
Annotation
• Predict protein• Extract ORFs• Remove errors• Compare with database of ‘known
function proteins’• Provide transitive annotations
NC
BI
Positional Cloning
NC
BI
Positional Candidate Cloning
NC
BI
The new information is always partial
• Complete Eukaryotic Genomes
• Ongoing Eukaryotic• Prokaryotic Ongoing• Published• Even a complete genome is only
partially understood
NC
BI
Why not use the genome sequence once its ‘ready’?
• Finding exons– 30% overprediction– 20% not found at all– Comparison systems rely on EST sequences
which themselves contain large error rates– Others are looking through partial data– Once the genome is done …when?
• Expressed sequences are there in part and represent a very very powerful key.
NC
BI
Interpreting data from many sources
NC
BI
Genomics and Tropical Diseases
How Can Genomics Contribute to
the Control of Tropical Diseases?
Challenges and Opportunities
The Role of BioinformaticsStrategic emphases for research http://www.who.int/tdr/grants/strategic-emphases/default.htmWHO/TDR Genomics and World Health Report 2002
NC
BI
Why Pathogen Genomics?
“The power and cost-effectiveness of modern genome sequencing technology mean that complete genome sequences of 25 of the major bacterial and parasitic pathogens could be available within five years. For about 100 million dollars (…), we could buy the sequence of every virulence determinant, every protein antigen and every drug target.”
B. Bloom (1995) A microbial minimalist. Nature 378:236
NC
BI
Genomics and Drug Development for Tropical Diseases: Challenges
• Knowledge limitations– A large proportion of pathogen genes have unknown
function– Heavy investment in genomics is done by the commercial
sector and therefore not widely available
• Emphasis and priorities– Genomes of non-pathogenic model organisms (S.
cerevisiae, D. melanogaster, C. elegans, A. thaliana)– Genomes of pathogens that affect individuals in
developed countries– Neglected diseases neglected pathogens
NC
BI
Doing Successful Science in the new millennium
• Huge increase in available biological information• Classic paradigm of ‘molecular biology’ now is
altering rapidly to genomics• Understanding of the new paradigms concerns more
than ‘just bench biology’• Discovery requires large scale systems and broad
collaborations, Global problems• Funding comes in large amounts at group level, no
longer a single laboratory or institution effort.• Accountable output
NC
BI
The Bigger Picture (Malaria)
NC
BI
Genomics Approach to Drug Development: Opportunities
• Classical laboratory assays aim at targets in which mutation is lethal to the pathogen– Valuable targets can be missed
• Sulphonamides: Inhibition of the p-aminobenzoic acid pathway not lethal for growth in laboratory but severely attenuate the capacity to cause disease
NC
BI
Genomics Approach to Drug Development: Opportunities
• New approaches for the identification of gene products specifically involved in the disease process may uncover further drug targets– Signature tagged mutagenesis (STM)– Transposon site hybridization (TraSH)
• Pathogen genomics and data mining for the discovery of new drug targets
NC
BI
Fosmidomycin • September
1999: a basic science breakthrough (data mining through bioinformatics identify new targets for chemotherapy of malaria)
• 1st semester 2001: Results of Phase I clinical trials
NC
BI
Fosmidomycin example - lesson
• A lesson to take home: 1½ years from data mining and laboratory research to phase II, proof-of-principle clinical trials
NC
BI
Bioinformatics: Opportunities in Health Research and Development
• New drug research and development– Identification of novel drug/vaccine targets– Structural predictions– Tapping into biodiversity– Reconstruction of metabolic pathways– Systems biology
• Identification of vaccine candidates through analysis of surface antigens and epitopes
NC
BI
A Window of Opportunity for Disease Endemic Countries
• Bioinformatics is an extremely important tool, with relevance to studying pathogenic organisms– Pathogens of interest to DECs already being
sequenced (e.g. P. falciparum, T. cruzi, T. brucei, Leishmania sp.)
• Computational biology is ‘people-intensive’, less affected by infrastructure, economics, etc than other areas of biological research
• ‘Critical mass’ issues less critical – a world-wide community is within reach
NC
BI
• Linux operating system permits use of the personal computer as a powerful workstation– Vast repository of public domain software for
computational biology
• Individual accounts for remote access and data processing can be open at high-performance computer facilities and regional centers– EMB network nodes, FIOCRUZ (Brazil), SANBI
(South Africa), CECALCULA (Venezuela), ICGEB (Trieste and New Delhi)
Relatively Modest Hardware Needs
and Technical Support
NC
BI
• Powerful searches using public websites– NCBI, EMB nodes, Sanger Center,
Expasy/SwissProt, KEGG database
• High-speed internet access is becoming more and more available in disease endemic countries through regional and international support, e.g.:– Asia-Pacific Advanced Network Consortium
(APAN) http://www.th.apan.net/– MIMCom Malaria Research Resources
http://www.nlm.nih.gov/mimcom/about.html
Relatively Modest Hardware
Needs and Technical Support
NC
BI
TDR Regional Training Centers & Regional Training Courses on Bioinformatics Applied to Tropical Diseases
• Africa– SANBI, Cape Town, South Africa
• Course: Jan 20-Feb 02, 2002; Mar 19-Apr 4, 2003; Feb 2-15, 2004 (with NBN series)
– Univ of Ibadan, Ibadan, Nigeria• Course: May 26-Jun 07, 2003
• South America– USP, São Paulo, Brazil
• Course: Feb 18-March 02, 2002; July 17-19, 2003; July 5-16, 2004;
• Southeast Asia– ICGEB, New Delhi, India
• Course: Apr 26-May 09, 2002; Sep 22-Oct 06, 2003; Sept 28-Oct 11, 2004
– Mahidol University, Bangkok, Thailand• Course: Jul 09-23, 2002; Sep 29-Oct 10, 2003; July 26-
Aug6, 2004
International Training Course on Bioinformatics and Computational Biology Applied to Genome Studies (Train-the-
trainers Workshop)May 21-June 15, 2001 FIOCRUZ, Brazil
NC
BI
Training Course on Bioinformatics and Functional Genomics Applied to Insect Vectors
of Human DiseasesAt the
Center for Bioinformatics and Applied Genomics (CBAG) and Center for Vector and Vector-Borne
Diseases (CVVD), Faculty of Science, Mahidol University,
Bangkok, ThailandJanuary 17-28, 2005
Training Course on Functional Genomics of Insect Vectors of Human Diseases
African Center for Training in Functional Genomics of Insect Vectors of Human Diseases
(AFRO VECTGEN) At the Malaria Research and Training Center (MRTC),
Bamako, MaliDec 1-16, 2004
NC
BI
Beginning Bioinformatics Books
• Baxevanis & Ouellette 2001. Bioinformatics: A Practical Guide to the Analysis of Genes and Proteins 2nd Edition. John Wiley Publishing.
• Gibas & Jambeck 2001. Developing Bioinformatics Computer Skills. O’Reilly.
• Bioinformatics: Genome Sequence Analysis Mount 2001
• Bioinformatics For Dummies – Claverie & Notredame 2003
• Bioinformatics and Functional Genomics Pesvner 2003
• Introduction to Bioinformatics – Lesk 2002• Fundamental Concepts of Bioinformatics Krane &
Raymer 2003• Beginning Perl for Bioinformatics – Tisdall 2002• Primer of Genome Science – Gibson & Muse 2002
NC
BI
Course Schedule
Comments and Suggestions
Take out your course schedule.
NC
BI
The Challenge
What is expected of you?