differentially expressed in FDCP 6 (DEF-6, IRF4-binding protein, DEF6, IBP)

Function

• PtdInsP3-dependent guanine nucleotide exchange factor
• role in activation of Rho GTPases RAC1, RhoA & CDC42
• regulates cell morphology in cooperation with activated RAC1 (putative)
• role in Th2 (T helper cells) development &/or activation, via interfering with ZAP-70 signaling (putative)
• interacts with ZAP70
• interacts with IRF4, activated RAC1 & F-actin
• Tyr-phosphorylated by tyrosine-protein kinase LCK in response to T-cell activation
• both the phosphorylated & non-phosphorylated forms bind PtdInsP3

Structure

• contains 1 PH domain, essential for PtdInsP3 binding

Compartment

• cytoplasm, cell membrane, nucleus
• recruited to the plasma membrane upon binding PtdInsP3

Alternative splicing

named isoforms=1

Expression

• broadly expressed in the immune system
• detected in T & B-cells

More general terms

• phosphoprotein
• guanine nucleotide exchange factor

Database

• UniProt: http://www.uniprot.org/uniprot/Q9H4E7.html