Segmental labeling of ASAP1-PZA for structural studies by nuclear magnetic resonance and neutron reflectometry

Abstract

ASAP1 is an Arf GTPase Activating Protein (ArfGAP) that participates in the regulation of actin-dependent membrane traffic and organelle structure by stimulating the activity of the small GTPase Arf1 at the membrane, thereby converting Arf1·GTP to Arf1·GDP. The core catalytic domain of ASAP1—referred to as ASAP1-PZA—is composed of a Pleckstrin homology (PH) domain ([325-451]—ASAP1, ∼14 kDa), immediately N-terminal to the catalytic Arf GAP domain ([458-724]—ASAP1 or ZA domain, ∼30 kDa); these two domains are connected by a short linker.