Publication Abstract from PubMed
rna1p is the Schizosaccharomyces pombe ortholog of the mammalian GTPase-activating protein (GAP) of Ran. Both proteins are essential for nuclear transport. Here, we report the crystal structure of rna1p at 2.66 A resolution. It contains 11 leucine-rich repeats that adopt the nonglobular shape of a crescent, bearing no resemblance to RhoGAP or RasGAP. The invariant residues of RanGAP form a contiguous surface, strongly indicating the Ran-binding interface. Alanine mutations identify Arg-74 as a critical residue for GTP hydrolysis. In contrast to RasGAP and RhoGAP, Arg-74 could be substituted by lysine and contributed significantly to the binding of Ran. Therefore, we suggest a GAP mechanism for rna1p, which constitutes a variation of the arginine finger mechanism found for Ras GAP and RhoGAP.
The crystal structure of rna1p: a new fold for a GTPase-activating protein.,Hillig RC, Renault L, Vetter IR, Drell T 4th, Wittinghofer A, Becker J Mol Cell. 1999 Jun;3(6):781-91. PMID:10394366[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
