The fastest‐actin‐based motor protein from the green algae, Chara, and its distinct mode of interaction with actin

FEBS Letters

Kagami, Osamu³  Iwasawa, Hidehiro⁴  Higashi-Fujime, Sugie⁴  Ishikawa, Ryoki²  Kohama, Kazuhiro²  Hozumi, Tetsu¹  Kurimoto, Eiji⁵ 

[1] Department of Physiology, Medical School, Nagoya City University, Mizuhoku, Nagoya, Japan;Department of Pharmacology, School of Medicine, Gunma University, Maebashi, Gunma, Japan;Department of Zoology, School of Science, Tokyo University, Bunkyoku, Tokyo, Japan;Department of Molecular Biology, Faculty of Science, Nagoya University, Chikusaku, Nagoya, Japan;Faculty of Pharmaceutical Science, Medical School, Nagoya City University, Mizuhoku, Nagoya, Japan

关键词: Motility (in vitro);    Actin-based movement;    Cleaved actin;    Motor protein;    Chara;    DTT;    dithiothreitol;    PMSF;    phenylmethylsulfonyl fluoride;    HMM;    heavy meromyosin;   

DOI  :  10.1016/0014-5793(95)01208-V

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The endoplasmic streaming in Characean cells is an actin-dependent movement. The motor protein responsible for the streaming was partially purified and characterized. It was soluble at low ionic strength, an ATPase of a molecular mass of 225 kDa and activated more than 100 times by muscle F-actin. Surprisingly, in an in vitro motility assay, the motor protein moved muscle F-actin at 60 μm/s, which is similar to the velocity of streaming in a living cell and 10 times faster than muscle myosin. Proteolytic cleavage of actin impaired movement crucially on muscle myosin, but did not affect movement at all on the Chara motor protein, suggesting that the Chara motor protein would interact with actin via a set of sites different from those of muscle myosin.

【 授权许可】

Unknown