Abstract

SH3 (Src Homolgy 3) domains are small protein modules of about 50-60 residues. It is found in proteins involved in several biological processes as diverse as signal transduction pathways, cytoskeleton organization, membrane traffic or organelle assembly. SH3 domains bind to proline-rich peptides that form a left-handed polyproline type II helix (PPII) in one of two opposite orientations. Ligand orientation depends on the position of the positive residue in the target peptide. Peptides that bind in a type I orientation contain the consensus R/KXXPXXP, while the type II orientation conform to the PXXPXR/K consensus

 Selected references

 This ELM has been assigned the following Gene Ontology (GO) terms for biological process, cellular component and molecular function.

Biological Process
cell growth and/or maintenance	GO:0008150
signal transduction	GO:0007165
cell communication	GO:0007154
Cellular Component
focal adhesion	GO:0005925
cytosol	GO:0005829
Molecular Function
Binding	GO:0005488
protein binding	GO:0005515
protein domain specific binding	GO:0019904
SH3-domain binding	GO:0017124