Characterization of the myosin-binding subunit of smooth muscle myosin phosphatase.
Characterization of the myosin-binding subunit of smooth muscle myosin phosphatase.
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DOI：
10.1016/s0021-9258(18)43828-8
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发表时间：
1994-12
期刊：
影响因子：
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通讯作者：
Hiroyuki Shimizu;Masaaki Ito;M. Miyahara;K. Ichikawa;S. Okubo;Tokuji Konishi;Michiko Naka;Toshio Tanaka;K. Hirano;D. Hartshorne
中科院分区：
文献类型：
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作者：
Hiroyuki Shimizu;Masaaki Ito;M. Miyahara;K. Ichikawa;S. Okubo;Tokuji Konishi;Michiko Naka;Toshio Tanaka;K. Hirano;D. Hartshorne
从鸡砂囊平滑肌中纯化了一种肌球蛋白磷酸酶。全酶是三聚体，由130，000-、38，000-和20，000-Da亚基组成（与Alessi等人的结果一致：Alessi，D.，麦克杜格尔湖K.，索拉湾M.，Ikebe，M.，和Cohen，P.（1992）Eur. 210，1023-1035）。催化亚基，38，000 Da，是1型δ同种型，其衍生的氨基酸序列与大鼠同种型相同。较大的亚基与肌球蛋白结合，也与催化亚基相互作用。从鸡砂囊cDNA文库中分离出编码该大亚基的cDNA克隆。重叠克隆表明存在两种异构体，并获得2889和3012个碱基的开放阅读框。这些编码蛋白质的963和1004个氨基酸，质量分别为106，700和111，600 Da。较大同种型中的插入物位于分子的中心，在残基512-552处。分子的N-末端三分之一由八个重复序列组成，类似于cdc 10/SWI 6或锚蛋白重复序列。肌球蛋白结合和与催化亚基结合是代表分子N-末端部分的58，000-Da片段的特性。
A myosin phosphatase was purified from chicken gizzard smooth muscle. The holoenzyme is a trimer and consists of 130,000-, 38,000-, and 20,000-Da subunits (in agreement with the results of Alessi et al.: Alessi, D., MacDougall, L. K., Sola, M. M., Ikebe, M., and Cohen, P. (1992) Eur. J. Biochem. 210, 1023-1035). The catalytic subunit, 38,000 Da, is the type 1 delta isoform, and its derived amino acid sequence is identical to the rat isoform. The larger subunit bound to myosin and also interacted with the catalytic subunit. cDNA clones encoding the large subunit were isolated from chicken gizzard cDNA libraries. Overlapping clones indicated the presence of two isoforms, and open reading frames of 2889 and 3012 bases were obtained. These encoded proteins of 963 and 1004 amino acids, with masses of 106,700 and 111,600 Da, respectively. The insert in the larger isoform is in the center of the molecule, at residues 512-552. The N-terminal third of the molecule is composed of eight repeat sequences, similar to the cdc10/SWI6 or ankyrin repeat. Myosin binding and binding to the catalytic subunit are properties of a 58,000-Da fragment that represents the N-terminal part of the molecule.