Author:
Burtnick L. D.,McCubbin W. D.,Kay C. M.
Abstract
TN-C was purified from bovine cardiac muscle. In the absence of Ca2+, cardiac TN-C has an intrinsic sedimentation coefficient of 1.93 S and a molecular weight of 18 000 daltons. Cardiac TN-C reverses the inhibitory effect of skeletal TN-I on the Mg2+-activated ATPase of a skeletal synthetic actomyosin preparation in the presence of skeletal tropomyosin. Circular dichroism (CD) studies indicate that cardiac TN-C undergoes a major conformational Change upon binding Ca2+. A similar response is elicited by Sr2+, whereas Mg2+ has a much less pronounced effect. The presence of Mg2+ does not alter the net effects of either Ca2+ or Sr2+. Cardiac TN-C is rich in acidic amino acid residues. UV absorption, near UV CD, and fluorimetric studies show that the protein lacks tryptophan and has a relatively high phenylalanine to tyrosine ratio. The results of this study invite direct comparisons with results reported for the skeletal muscle analogue of cardiac TN-C.
Publisher
Canadian Science Publishing
Cited by
31 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献