BRAG2/GEP100/IQSec1 interacts with clathrin and regulates α5β1 integrin endocytosis through activation of ADP ribosylation factor 5 (Arf5).

ABSTRACT: ADP ribosylation factors (Arfs) are small GTP-binding proteins known for their role in vesicular transport, where they nucleate the assembly of coat protein complexes at sites of carrier vesicle formation. Similar to other GTPases, Arfs require guanine nucleotide exchange factors to catalyze GTP loading and activation. One subfamily of ArfGEFs, the BRAGs, has been shown to activate Arf6, which acts in the endocytic pathway to control the trafficking of a subset of cargo proteins including integrins. We have previously shown that BRAG2 modulates cell adhesion by regulating integrin surface expression. Here, we show that, in addition to Arf6, endogenous BRAG2 also activates the class II Arfs, Arf4 and Arf5, and that surprisingly, it is Arf5 that mediates integrin internalization. We observed

SUBMITTER: Moravec R 

PROVIDER: S-EPMC3438945 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature