期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2003
卷号：100
期号：24
页码：13851-13856
DOI：10.1073/pnas.2233339100
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：This study characterizes the interactions between kabiramide C (KabC) and related macrolides and actin and establishes the mechanisms that underlie their inhibition of actin filament dynamics and cytotoxicity. The G-actin-KabC complex is formed through a two-step binding reaction and is extremely stable and long-lived. Competition-binding studies show that KabC binds to the same site on G-actin as Gelsolin domain 1 and CapG. KabC also binds to protomers within F-actin and results in the severing and capping of the (+) end; these studies suggest that free KabC and related macrolides act as biomimetics of Gelsolin. The G-actin-KabC complex binds to the (+) end of a growing filament, where it functions as a novel, unregulated, (+)-end capper and is largely responsible for the inhibition of motility and cytokinesis in {approx}10 -100 nM KabC-treated cells. KabC and related macrolides are useful probes to study the regulation of the actin filament (+) end and may lead to new therapies to treat diseases of the actin cytoskeleton.
