SH3 domain-containing guanine exchange factor (SGEF, ARHGEF26)

Function

• activates RhoG GTPase by promoting the exchange of GDP by GTP
• required for the formation of membrane ruffles during macropinocytosis
• required for the formation of cup-like structures during trans-endothelial migration of leukocytes
• interacts with ICAM1 & RHOG

Structure

• contains 1 DH (DBL-homology) domain
• contains 1 PH domain
• contains 1 SH3 domain

Compartment

cell projection, ruffle

Alternative splicing

named isoforms=3

Expression

isoform 1 is broadly expressed, with highest levels in liver (at protein level). isoform 2 is sspecifically expressed in prostate & liver

Pathology

• in case of Salmonella enterica infection, activated by SopB, which induces cytoskeleton rearrangements & promotes bacterial entry
• isoform 2 is up-regulated by androgens in prostate cancer cells

More general terms

• guanine nucleotide exchange factor

Database

• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:2608
• UniProt: http://www.uniprot.org/uniprot/Q96DR7.html