Inverse interaction between tropomyosin and phosphorylated myosin in the presence or absence of caldesmon  

作　　者：Ying Zhang Houli Zhang Zeyao Tang Kazuhiro Kohama Yuan Lin 

机构地区：[1]Department of Pharmacology, Dalian Medical University, Dalian 116044, China [2]Department of Molecular and Cellular Pharmacology, Gtmma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan

出　　处：《Acta Biochimica et Biophysica Sinica》2013年第7期601-606,共6页生物化学与生物物理学报（英文版）

基　　金：We would like to thank Ms Zhi Lin and Professor Xin Jiang for their helpful comments.This work was supported by grants from the National Natural Science Foundation of China （No. 30772601 and 30070203）.

摘　　要：In the present study, co-sedimentation assay, intrinsic fluorescence intensity measurement, and Mg^2＋-ATPase ac-tivity analysis were carried out to investigate the direct effect of tropomyosin （TM） on unphosphorylated myosin （UM） or phosphorylated myosin （PM） in the presence or absence of ealdesmon （CAD）. Results showed that TM sig- nificantly decreased the sedimentation, intrinsic fluores-cence intensity, and the Mge^-ATPase activity of PM, but not UM. In the presence of CaD, TM also significantly decreased these parameters irrespective of myosin phos- phorylation, suggesting that the interaction between TM and CaD abolished the effects of TM on PM or UM and that there was an inverse interaction between TM and PM, characterized by the decreased PM sedimentation and intrinsic fluorescence intensity.In the present study, co-sedimentation assay, intrinsic fluorescence intensity measurement, and Mg^2＋-ATPase ac-tivity analysis were carried out to investigate the direct effect of tropomyosin （TM） on unphosphorylated myosin （UM） or phosphorylated myosin （PM） in the presence or absence of ealdesmon （CAD）. Results showed that TM sig- nificantly decreased the sedimentation, intrinsic fluores-cence intensity, and the Mge^-ATPase activity of PM, but not UM. In the presence of CaD, TM also significantly decreased these parameters irrespective of myosin phos- phorylation, suggesting that the interaction between TM and CaD abolished the effects of TM on PM or UM and that there was an inverse interaction between TM and PM, characterized by the decreased PM sedimentation and intrinsic fluorescence intensity.

关 键 词：smooth muscle myosin TROPOMYOSIN CALDESMON inverse protein-protein interaction 

分 类 号：TP391.72[自动化与计算机技术—计算机应用技术] S551.403.2[自动化与计算机技术—计算机科学与技术]