生命过程小分子调节剂的研究：A Novel Small Molecule Regulator of Guanine Nucleotide Exchange Activity ...
关键字: A Novel Small Molecule Regulator 发布者：Heling Pan , Dawei Ma , and Junying Yuan 发布时间：2009-03-02 18:03:24 点击数: 6176次
J. Biol. Chem.2008, 283, 31087-31096.
A Novel Small Molecule Regulator of Guanine Nucleotide Exchange Activity of the ADP-ribosylation Factor and Golgi Membrane Trafficking*
Heling Pan , Jia Yu , Lihong Zhang , Anne Carpenter 1, Hong Zhu¶, Li Li , Dawei Ma 2, and Junying Yuan¶3
State Key Laboratory of Bioorganic & Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China, Broad Institute of Harvard and Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, and the ¶Department of Cell Biology, Harvard Medical School, Boston, Massachusetts 02115
Abstract: An image-based phenotypic screen was developed to identify smallmolecule regulators of intracellular traffic. Using this screenwe found that AG1478, a previously known inhibitor of epidermalgrowth factor receptor, had epidermal growth factor receptor-independentactivity in inducing the disassembly of the Golgi in human cells.Similar to brefeldin A (BFA), a known disrupter of the Golgi,AG1478 inhibits the activity of small GTPase ADP-ribosylationfactor. Unlike BFA, AG1478 exhibits low cytotoxicity and selectivelytargets the cis-Golgi without affecting endosomal compartment.We show that AG1478 inhibits GBF1, a large nucleotide exchangefactor for the ADP-ribosylation factor, in a Sec7 domain-dependentmanner and mimics the phenotype of a GBF1 mutant that has aninactive mutation. The treatment with AG1478 leads to the recruitmentof GBF1 to the vesicular-tubular clusters adjacent to the endoplasmicreticulum exit sites, a step only transiently observed previouslyin the presence of BFA. We propose that the treatment with AG1478delineates a membrane trafficking intermediate step that dependsupon the Sec7 domain.