How are protein sequence variety and protein diversity represented in UniProtKB?

The article C. R. Biol. (2005) (updated version) gives an overview on cellular processes that can lead to sequence variety and structural diversity in eukaryotes. It explains, with examples, how such processes are represented in UniProtKB.

Further examples can be found in the online tutorial.

This tutorial also shows how to use the UniProtKB annotation to extract specific datasets of entries, e.g.:

• proteins containing a selenocysteine
• proteins whose sequences are derived from a RNA editing event
• proteins containing a GPI-anchor...

Remark: Three types of qualifiers are used to describe information that is not based on experimental findings: Potential, Probable, By similarity

Example of query:

• proteins phosphorylated on serine (Experimentally proven, Potential, Probable or By similarity)
• proteins which have been experimentally proven to be phosphorylated on a serine ...

Note: Examples on the website might differ slightly from those printed in the article, due to format changes and updates to the annotation.

Related terms: post-translational modification, posttranslational modification, PTM, alternative splicing, variant, isoform, mRNA editing, ribosomal frameshifting.

See also:

• What is the canonical sequence? Are all isoforms described in one entry?
• How do we manually annotate a UniProtKB entry?
• Alternative products
• Alternative sequence