Rap-specific GTPase Activating Protein follows an Alternative Mechanism

Rab GTPase-activating protein domain

Cristinel P. MÎINEA*1, Hiroyuki SANO*1, Susan KANE*, Eiko SANO*, Mitsunori FUKUDA†, Johan PERÄNEN‡, William S. LANE§ and Gustav E. LIENHARD*2 *Department of Biochemistry, Dartmouth Medical School, Hanover, NH 03755, U.S.A., †Fukuda Initiative Research Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan, ‡Institute of Biotechnology, Program in Cellular Biotechnology, FIN-00014, University o...

ARHGAP20 (Rho GTPase activating protein 20)

Structural basis for activation and non-canonical catalysis of the Rap GTPase activating protein domain of plexin

Plexins are cell surface receptors that bind semaphorins and transduce signals for regulating neuronal axon guidance and other processes. Plexin signaling depends on their cytoplasmic GTPase activating protein (GAP) domain, which specifically inactivates the Ras homolog Rap through an ill-defined non-canonical catalytic mechanism. The plexin GAP is activated by semaphorin-induced dimerization, ...

Alternative splicing of Rac1 generates Rac1b, a self-activating GTPase.

Rac1b was recently identified in malignant colorectal tumors as an alternative splice variant of Rac1 containing a 19-amino acid insertion next to the switch II region. The structures of Rac1b in the GDP- and the GppNHp-bound forms, determined at a resolution of 1.75 A, reveal that the insertion induces an open switch I conformation and a highly mobile switch II. As a consequence, Rac1b has an ...

The GTPase Activating Rap/RanGAP Domain-Like 1 Gene Is Associated with Chicken Reproductive Traits

BACKGROUND Abundant evidence indicates that chicken reproduction is strictly regulated by the hypothalamic-pituitary-gonad (HPG) axis, and the genes included in the HPG axis have been studied extensively. However, the question remains as to whether any other genes outside of the HPG system are involved in regulating chicken reproduction. The present study was aimed to identify, on a genome-wide...