Adducin regulation - Definition of the calmodulin-binding domain and sites of phosphorylation by protein kinase A and C
Adducin regulation - Definition of the calmodulin-binding domain and sites of phosphorylation by protein kinase A and C
复制标题
DOI：
10.1074/jbc.271.41.25157
复制
发表时间：
1996-10-11
影响因子：
4.8
通讯作者：
Bennett, V
中科院分区：
文献类型：
--
作者：
Matsuoka, Y;Hughes, CA;Bennett, V
内收蛋白促进血影蛋白与肌动蛋白的结合，并覆盖肌动蛋白丝快速生长的末端。内收蛋白包含 N 端核心、颈和 C 端尾结构域，是蛋白激酶 A (PKA) 和 C (PKC) 的底物，并与 Ca2+/钙调蛋白结合。 α-和 β-内收蛋白 C 端 MARCKS 相关结构域中的 Ser-726 和 Ser-713 分别被鉴定为 PKA 和 PKC 共有的主要磷酸化位点，此外，PKA 还磷酸化了颈结构域中的 Ser-408、-436 和 -481 处的 α-内收蛋白。PKA（而非 PKC）磷酸化，降低了内收蛋白对内收蛋白的亲和力。血影蛋白-F-肌动蛋白复合物以及内收蛋白促进血影蛋白与 F-肌动蛋白结合的活性。 β-内收蛋白的肉豆蔻酰化富含丙氨酸的蛋白激酶 C 底物相关结构域被确定为主要的 Ca2+ 依赖性钙调蛋白结合位点。 PRA 和 PRC 对 β-内收蛋白和 MARCKS 相关结构域肽的磷酸化可抑制钙调蛋白结合。钙调蛋白反过来抑制 PKA 磷酸化 β-内收蛋白（而非 α-内收蛋白）的磷酸化速率，但不抑制其磷酸化程度，以及 PKC 抑制每个亚基的磷酸化程度。这些发现表明钙调蛋白结合调节内收蛋白功能与 PKA 和 PKC 磷酸化之间存在复杂的相互关系。
Adducin promotes association of spectrin with actin and caps the fast growing end of actin filaments. Adducin contains N-terminal core, neck, and C-terminal tail domains, is a substrate for protein kinases A (PKA) and C (PKC), and binds to Ca2+/calmodulin. Ser-726 and Ser-713 in the C-terminal MARCKS-related domains of alpha- and beta-adducin, respectively, were identified as the major phosphorylation sites common for PKA and PKC, PKA, in addition, phosphorylated alpha-adducin at Ser-408, -436, and -481 in the neck domain, Phosphorylation by PKA,but not PKC, reduced the affinity of adducin for spectrin-F-actin complexes as well as the activity of adducin in promoting binding of spectrin to F-actin. The myristoylated alanine-rich protein kinase C substrate-related domain of beta-adducin was identified as the dominant Ca2+-dependent calmodulin-binding site. Calmodulin-binding was inhibited by phosphorylation of beta-adducin and of a MARCKS-related domain peptide by PRA and PRC. Calmodulin in turn inhibited the rate, but not the extent, of phosphorylation of beta-adducin, but not alpha-adducin, by PKA and that of each subunit by PKC. These findings suggest a complex reciprocal relationship between regulation of adducin function by calmodulin binding and phosphorylation by PKA and PKC.