An Arf1 GTPase mutant with different responses to GEF inhibitors

作者:Flisiak Sebastian; Zeeh Jean Christophe; Guibert Bernard; Cherfils Jacqueline*; Zeghouf Mahel
来源:Biochemical and Biophysical Research Communications, 2008, 377(1): 156-160.
DOI:10.1016/j.bbrc.2008.09.107

摘要

Guanine nucleotide exchange factors (GEFs) stimulate the activation of small GTP-binding proteins (GTP-ases). Establishing their specificity is a challenging issue, in which chemical genetics are rapidly gaining interest. We report a mutation in the Arf1 GTPase, K38A, which differentially alters its sensitivity to GEF inhibitors. The mutation renders Arf1 insensitive to LM11, a GEF inhibitor that we previously discovered by structure-based screening. In contrast, full inhibition by the natural compound Brefeldin A (BFA) is retained. We show that the mutation is otherwise silent towards the biochemical and cellular properties of Arf1, notably its binding to effectors as measured by a novel GEF-protection assay. This is thus the first GTPase mutant with different responses to two classes of inhibitors, and a novel tool to analyze Arf and ArfGEF specificity and functions in vitro and in cells.

  • 出版日期2008-12-5

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