Suppose I am working on diabetes and I would like to find all the solved protein structures which have been implicated in diabetes. I could find this information using UniProt in just a few steps. Following is how:

1. Go to http://www.uniprot.org
2. Choose UniProt Knowledgebase (UniProtKB) in the search field
3. Type "diabetes" in the Query field
4. UniProt returned around 700 entries
5. My first entry is Q14654. Click on this entry
6. Scroll down to read the annotation section
7. Involvement in disease is a particularly interesting section
8. Scroll down to the keywords in the Ontology section
9. Here I find out that this protein is involved in Diabetes Mellitus
10. Since this is keyword, I can use it to filter my results
11. Click on the back button of your browser
12. Click on the "keyword" link
13. Now click on the "Keywords" link. This would add keywords column to your search results
14. Click on the "Customize display" link
15. Add the 3D link and then click on Save
16. Click on the "Show only entries with structural information" link
17. Now I see that proteins whose structure is solved using x-ray crystallography, NMR, or by modeling
18. I could scroll down and study the folds and search for other proteins containing similar folds. I could use cross-references to view the structure in PDB or MDB. It would soon become apparent that many proteins but only a few folds are involved in the diabetes.