白色骨骼肌肌钙蛋白T的磷酸化位点以及肌钙蛋白C与其相互作用对磷酸化酶激酶使其磷酸化的影响。

The phosphorylation sites of troponin T from white skeletal muscle and the effects of interaction with troponin C on their phosphorylation by phosphorylase kinase.

Moir A J, Cole H A, Perry S V

Biochem J. 1977 Feb 1;161(2):371-82. doi: 10.1042/bj1610371.

Abstract

The phosphorylation of troponin T from rabbit white sketetal muscle is catalysed by phosphorylase kinase, but not at a significant rate by bovine 3':5'-cyclic AMP-dependent protein kinase. 2. The amino acid sequences adjacent to the three major phosphorylation sites of troponin T were determined. 3. The serine in the N-terminal peptide (Asx,SerP, Glx)Glu-Val-Glu, is that phosphorylated (SerP, phosphoserine) when the troponin complex is isolated. 4. The other two sites of phosphorylation are located in the sequence Ala-Leu-(Ser, SerP)-Met-Gly-Ala-Asn-Tyr(Ser,SerP)Tyr. 5. When troponin T is phosphorylated in the presence of troponin C, the extent of phosphorylation at each site is considerably decreased. 6. CNBr fragments of troponin T are also phosphorylated by phosphorylase kinase, but the rate of phosphorylation at each site in the CNBr fragments is considerably slower than in the native protein. 7. From these studies it is suggested that troponin C interacts with troponin T in the region containing the two closely situated phosphorylation sites.

摘要

兔白色骨骼肌肌钙蛋白T的磷酸化由磷酸化酶激酶催化，但牛的3':5'-环腺苷酸依赖性蛋白激酶催化该反应的速率不显著。2. 测定了肌钙蛋白T三个主要磷酸化位点附近的氨基酸序列。3. 当分离肌钙蛋白复合物时，N端肽（Asx,SerP, Glx）Glu-Val-Glu中的丝氨酸是被磷酸化的（SerP，磷酸丝氨酸）。4. 另外两个磷酸化位点位于序列Ala-Leu-(Ser, SerP)-Met-Gly-Ala-Asn-Tyr(Ser,SerP)Tyr中。5. 当肌钙蛋白T在肌钙蛋白C存在的情况下被磷酸化时，每个位点的磷酸化程度会显著降低。6. 肌钙蛋白T的溴化氰片段也能被磷酸化酶激酶磷酸化，但溴化氰片段中每个位点的磷酸化速率比天然蛋白中的要慢得多。7. 从这些研究表明，肌钙蛋白C在含有两个紧密相邻磷酸化位点的区域与肌钙蛋白T相互作用。