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:2009
卷号:106
期号:20
页码:8175-8179
DOI:10.1073/pnas.0811131106
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Much of the transport, tension, and movement in mitosis depends on kinesins, the ATP-powered microtubule-based motors. We report the crystal structure of a kinesin complex, the mitotic kinesin KCBP bound to its principal regulator KIC. Shown to be a Ca2+ sensor, KIC works as an allosteric trap. Extensive intermolecular interactions with KIC stabilize kinesin in its ADP-bound conformation. A critical component of the kinesin motile mechanism, called the neck mimic, switches its association from kinesin to KIC, stalling the motor. KIC denies access of the motor to its track by steric interference. Two major features of this regulation, allosteric trapping and steric blocking, are likely to be general for all kinesins.