DEP domain-containing protein 2 (phosphatidylinositol 3,4,5-trisphosphate-dependent Rac exchanger 2, PtdIns(3,4,5)-dependent Rac exchanger 2, P-Rex2, DEPDC2, PREX2)

Function

• RAC1 guanine nucleotide exchange factor (GEF)
• activates Rac proteins by exchanging bound GDP for free GTP
• synergistically activated by PIP3 & the beta gamma subunits of heterotrimeric G protein
• mediates activation of RAC1 in a PI3K-dependent manner
• role in Rac signaling
• acts downstream of both G protein-coupled receptors & phosphoinositide 3-kinase
• interacts with RAC1

Structure

• PH domain confers substrate specificity & recognition able to discriminate between RAC1, RHOA, CDC42
• DH domain alone was unable to confer substrate specificity & recognition
• contains 2 DEP domains
• contains 1 DH domain (DBL-homology domain)
• contains 2 PDZ domain (DHR domains)
• contains 1 PH domain

Alternative splicing

named isoforms=3

Expression

• isoform 1: highly expressed in skeletal muscle, heart, placenta, absent from peripheral blood leukocytes
• isoform 2 is expressed in skeletal muscle, kidney, small intestine, placenta
• isoform 3 is expressed in the heart

More general terms

• DEP domain-containing protein 5 (DEPDC)
• guanine nucleotide exchange factor

Database

• UniProt: http://www.uniprot.org/uniprot/Q70Z35.html