Pressure study reveals conformational landscapes and structural transitions of small GTPase

Abstract

ADP ribosylation factors (Arfs) function in regulation of vesicular transport with lipids and protein trafficking in eukaryotic cells. Arf GTPase activity is activated by Guanine nucleotide Exchange Factors (GEFs); then inactivated upon binding GTPase Activating Proteins (GAPs). As a GDP/GTP switch, massive conformational differences between the GDP- and GTP-bound forms are observed in the N-terminal and switch regions of Arfs. In addition, previous studies suggest the N-terminal helix controls the conformational transitions of GDP/GTP switch that involves local unfolding.