Integrin-linked kinase is responsible for Ca2+-independent myosin diphosphorylation and contraction of vascular smooth muscle.
Integrin-linked kinase is responsible for Ca2+-independent myosin diphosphorylation and contraction of vascular smooth muscle.
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整合素连接激酶负责 Ca2+ 独立的肌球蛋白二磷酸化和血管平滑肌的收缩。
DOI:
10.1042/bj20051173
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发表时间:
2005
期刊:
影响因子:
--
通讯作者:
M. Walsh
中科院分区:
文献类型:
--
作者:
David P. Wilson;C. Sutherland;M. Borman;J. Deng;J. MacDonald;M. Walsh
Smooth muscle contraction is activated by phosphorylation at Ser-19 of LC20 (the 20 kDa light chains of myosin II) by Ca2+/calmodulin-dependent MLCK (myosin light-chain kinase). Diphosphorylation of LC20 at Ser-19 and Thr-18 is observed in smooth muscle tissues and cultured cells in response to various contractile stimuli, and in pathological circumstances associated with hypercontractility. MLCP (myosin light-chain phosphatase) inhibition can lead to LC20 diphosphorylation and Ca2+-independent contraction, which is not attributable to MLCK. Two kinases have emerged as candidates for Ca2+-independent LC20 diphosphorylation: ILK (integrin-linked kinase) and ZIPK (zipper-interacting protein kinase). Triton X-100-skinned rat caudal arterial smooth muscle was used to investigate the relative importance of ILK and ZIPK in Ca2+-independent, microcystin (phosphatase inhibitor)-induced LC20 diphosphorylation and contraction. Western blotting and in-gel kinase assays revealed that both kinases were retained in this preparation. Ca2+-independent contraction of calmodulin-depleted tissue in response to microcystin was resistant to MLCK inhibitors [AV25 (a 25-amino-acid peptide derived from the autoinhibitory domain of MLCK), ML-7, ML-9 and wortmannin], protein kinase C inhibitor (GF109203X) and Rho-associated kinase inhibitors (Y-27632 and H-1152), but blocked by the non-selective kinase inhibitor staurosporine. ZIPK was inhibited by AV25 (IC50 0.63+/-0.05 microM), whereas ILK was insensitive to AV25 (at concentrations as high as 100 microM). AV25 had no effect on Ca2+-independent, microcystin-induced LC20 mono- or di-phosphorylation, with a modest effect on force. We conclude that direct inhibition of MLCP in the absence of Ca2+ unmasks ILK activity, which phosphorylates LC20 at Ser-19 and Thr-18 to induce contraction. ILK is probably the kinase responsible for myosin diphosphorylation in vascular smooth muscle cells and tissues.
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影响因子:
4.8
作者:
Harada,T;Seto,M;Sasaki,Y;London,S;Luo,Z;Mayberg,M
通讯作者:
Mayberg,M
影响因子:
4.1
作者:
Murányi, A;MacDonald, JA;Hartshorne, DJ
通讯作者:
Hartshorne, DJ
DOI:
10.1016/s0021-9258(17)45384-1
发表时间:
1990-11
期刊:
The Journal of biological chemistry
影响因子:
--
作者:
R. Honkanen;J. Zwiller;R. Moore;S. L. Daily;B. Khatra;M. Dukelow;A. Boynton
通讯作者:
R. Honkanen;J. Zwiller;R. Moore;S. L. Daily;B. Khatra;M. Dukelow;A. Boynton
DOI:
--
发表时间:
1988
期刊:
The Journal of biological chemistry
影响因子:
--
作者:
Miller-Hance,WC;Miller,JR;Wells,JN;Stull,JT;Kamm,KE
通讯作者:
Kamm,KE
DOI:
10.1016/s0021-9258(17)42425-2
发表时间:
1986-01
期刊:
The Journal of biological chemistry
影响因子:
--
作者:
M. Ikebe;D. Hartshorne;M. Elzinga
通讯作者:
M. Ikebe;D. Hartshorne;M. Elzinga