Binding of the vesicle docking protein p115 to the GTPase Rab1b regulates membrane recruitment of the COPI vesicle coat.

ABSTRACT: Membrane recruitment of the COPI vesicle coat is fundamental to its function and contributes to compartment identity in the early secretory pathway. COPI recruitment is triggered by guanine nucleotide exchange activating the Arf1 GTPase, but the key exchange factor, GBF1, is a peripheral membrane component whose membrane association is dependent on another GTPase, Rab1. Inactive Rab GTPases are in a soluble complex with guanine nucleotide dissociation inhibitor (GDI) and activation of Rab GTPases by exchange factors can be enhanced by GDI dissociation factors (GDFs). In the present study, we investigated the vesicle docking protein p115 and it's binding to the Rab1 isoform Rab1b. Inhibition of p115 expression induced dissociation of Rab1b from Golgi membranes. Rab1b bound the cc2 domain of

SUBMITTER: Guo Y 

PROVIDER: S-EPMC4187009 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature