Caldesmon has two calmodulin-binding domains.
Caldesmon has two calmodulin-binding domains.
复制标题
Caldesmon 有两个钙调蛋白结合域。
DOI：
10.1016/0006-291x(89)92373-5
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发表时间：
1989
影响因子：
3.1
通讯作者：
Lu,RC
中科院分区：
文献类型：
--
作者：
Wang,CL;Wang,LW;Lu,RC
Chicken gizzard caldesmon was cleaved with chymotrypsin or CNBr, and the calmodulin-binding fragments were isolated using an affinity column. Limited chymotryptic digestion gives rise to a 38 kDa calmodulin-binding fragment (CT40) as described previously (Szpacenko, A. & Dabrowska, R., FEBS Lett. 202, 182–186, 1986; Fujii, T., Imai, M., Rosenfeld, GC & Bryan, J., J. Biol. Chem. 261, 16155–16160, 1987; Yazawa, M., Yagi, K. & Sobue, K., J. Biochem. 102, 1065–1073, 1987). In the case of CNBr cleavage a 37 kDa calmodulin-binding fragment (CB40) was obtained. Both CT40 and CB40 contain a reactive thiol group, but these thiols are apparently in different environments as judged by the responses of attached fluorescent labels to calmodulin-binding. A comparison of the N-terminal sequences of CB40 and CT40 with the complete sequence of caldesmon shows that the two calmodulin-binding fragments in fact originate from different parts of the parent molecule. Thus there exist two calmodulin-binding sites in caldesmon, one in the N-terminal half and the other in the C-terminal half of the molecule. This is consistent with the recent finding that up to two calmodulin molecules can be crosslinked to each caldesmon molecule (Wang, C.-LA, Biochem. Biophys. Res. Commun., 156, 1033–1038, 1988).
