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CACAO - Remote training
Gene Function and Gene OntologyFall 2011
http://gowiki.tamu.edu/wiki/index.php/Category:CACAO
“Scientists find gene that ...”
An avalanche of genes
• High throughput sequencing is finding genes faster than we can understand them
• Goals for annotation:– Where the genes are in
the genome
– What their functions are
Function annotation
• Allows us to– Infer the functions of genes
• Related by common descent
• Related by similar expression patterns
• Related by phylogenetic profiles
• ...
Function annotation
• Allows us to – Understand the capabilities of
organisms genomes
– Understand patterns of gene expression• In different environments
• In different tissues
• In disease states
– ...
Classic MODel
Literature
Datasets
Curators(rate limiting)
Database
Requirements
• Accurate functional annotation for as many genes as possible
• A system of assigning function that allows both humans and computers to compare, contrast, analyze, and predict gene function
• Curators to make and/or check these assignments– For CACAO, we will teach you what
biocurators do.
CACAO
• Community
• Assessment– How well can
• Community – you (with our coaching)
• Annotation with– assign gene functions
• Ontologies– using GO?
CACAO is competitive
• Teams get points for complete annotations– GO term (right level of specificity)– reference– evidence code– identify where in the paper the evidence comes
from
• Teams can take away points from competitors by challenging annotations– finding a problem– suggesting a better alternative
What’s in it for you (besides credit)?
– We hope you will • learn how we think
about gene function
• gain skills that will help your future career
• enjoy contributing to a resource used by people all over the world
• have fun!
The gist of CACAO…
Finding evidence(in papers)
Making annotations
Using GO terms
GO = Gene Ontology
• Controlled vocabulary– Everyone uses the same terms
– Terms have IDs that computers can understand
• Relationships between functions
Gene OntologyA common system for describing gene function
GO
• 3 aspects (ontologies) for gene products
1. Biological Process
2. Molecular Function
3. Cellular Component
• Used to make annotations– aka Gene associations– Term + qualifiers + evidence code + reference etc.
Molecular Function
• activities or “jobs” of a gene product
glucose-6-phosphate isomerase activity
from GOCfigure from GO consortium presentations
Biological Processa commonly recognized series of events
cell division
Figure from Nature Reviews Microbiology 6, 28-40 (January 2008)
Cellular Component
• where a gene product acts
Key elements of a GO annotation
Submitted to GO consortium
Viewable on GONUTS
**Don’t worry - I will cover this again (several times)!
GO Annotation
• To make an annotation, you need to– Assign GO terms to genes (gene
products)• At appropriate level of specificity
• Sometimes with Qualifiers – NOT
– Contributes_to
– Colocalizes_with
– Record the evidence
Record the evidence
• Where it came from: – Reference (database accession)
• PMID:6987663
• Kind of evidence: – Evidence codes
• IMP: Inferred from Mutant Phenotype
• IDA: Inferred from Direct Assay
• …
CACAO - the “Community Annotation” part
What I am going to tell you about next is:1. How to choose proteins to annotate2. Finding GO terms & navigating a GO term page
3. Finding UniProt accessions4. Making gene pages on GONUTS & the anatomy of a gene page
5. How and where to add an annotation6. Where to look for your annotations & other teams’ annotations … (& the challenges!)
http://gowiki.tamu.edu/wiki/index.php/
Deciding what to annotate1. randomly
2. topics of interest (ie efflux pump proteins, biofilms)
3. papers you have come across while doing other stuff
4. methods you know or want to learn
5. phenotypes and mutants you are interested in
6. by author
7. by pathway or regulon
8. suggested by another (ie high IEA:manual annotation ratio)
9. current paper mentions another gene product
10. review papers (ie Annual Reviews are excellent sources)
EXAMPLE #1: let’s say you have a great paper (PMID:1111) that characterizes the tyrosine kinase activity of your
favorite protein (human p53)…
Part I: Where do you search for GO terms? GONUTS
http://gowiki.tamu.edu
• CHICK - AgBase (Gallus gallus)• dictyBase - dictyBase (Dictyostelium discoideum - slime mold)• FB - FlyBase (Drosophila melanogaster)• HUMAN - Reactome, BHF-UCL• MGI - Mouse genome informatics (Mus musculus - house mouse)• SGD - Saccharomyces genome database (Saccharomyces cerevisiase - yeast)• TAIR - The Arabidopsis Informatics Resource (Arabidopsis thaliana)• WB - WormBase (Caenorhabditis elegans)• ZFIN - Zebrafish model organism database (Danio rerio)
What do you actually need once you have found the correct term?
GO:0004713
Part II: You now have a paper, a protein & you found a suitable GO
term… what next?
• UniProt accession - http://www.uniprot.org
- Search (“Query”) & find the correct UniProt accession for your protein
- Look something like: P012A9
Part III: Where are you going to add your annotations? GONUTS
http://gowiki.tamu.edu
How do you make a new gene page in GONUTS?
• Use the UniProt accession to make a page that you will be able to add your own annotation to.
• GoPageMaker will:1. Check if the page exists in GONUTS & take you there if it does.2. Make a page & pull all of the annotations from UniProt into a
table that you can edit.
…
…
…
…
Where do you add an annotation? Add a row in the table.
What you must fill in (for every annotation)
GO:0004713
PMID:1111
IDA: Inferred from direct assay
Figure 2a
What you might also have to fill in
Not sure? Check the competition guidelines. Ask a coach (Jim, Debby, Adrienne or usually me)!
Where will your annotation now show up?
1. In the “Annotation” table on the gene page you just edited
2. In the table on your user pagehttp://gowiki.tamu.edu/wiki/index.php/User:Oherrera
3. In the table on your team pagehttp://gowiki.tamu.edu/wiki/index.php/Category:Team_That_Will_Beat_You!!!
4. As points on the scoreboardhttp://gowiki.tamu.edu/wiki/index.php/Category:CACAO_UW_Parkside
Questions?
At this point, you should be able to:1. Find GO terms on GONUTS2. Find UniProt accessions on UniProt3. Make a gene page on GONUTS4. Add an annotation
CACAO - the “Community Assessment” part
http://gowiki.tamu.edu/wiki/index.php/Category:CACAO_UW_Parkside
Example starting from a topic– Shiga toxin
PMID:2677606
Make page on GONUTS for Q7BQ98. Has
PMID:2677606 been annotated?
If it has, search PubMed for a different article.
http://www.ncbi.nlm.nih.gov/pubmed?term=2677606
GO:0009405 ?
What GO term? (hint: search GONUTS)