Human Kalirin/RAC1 GEF/GTPase Complex

We have cloned, expressed, purified and crystallised the first DH GEF domain of Kalirin (gene: KALRN) in complex with RAC1 (gene: RAC1) as part of a programme to explore a new way of targeting GTPases. Fragment screening and X-ray crystallography has identified binders within the orthosteric binding site. A nucleotide exchange assay has been developed and GEF activity established.

本研究作为探索靶向GTP酶（GTPases）新策略的项目组成部分，完成了卡林蛋白（Kalirin）首个DH型鸟苷酸交换因子结构域（DH GEF domain，编码基因为KALRN）与RAC1（编码基因为RAC1）所形成复合物的克隆、表达、纯化及结晶。通过片段筛选与X射线晶体学（X-ray crystallography）分析，已在该复合物的正构结合位点（orthosteric binding site）中鉴定出结合配体。目前已建立核苷酸交换实验（nucleotide exchange assay）体系，并验证了其鸟苷酸交换因子活性。