Phosphorylation of Rho-associated kinase (Rho-kinase/ROCK/ROK) substrates by protein kinases A and C
Phosphorylation of Rho-associated kinase (Rho-kinase/ROCK/ROK) substrates by protein kinases A and C
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DOI：
10.1016/j.biochi.2006.08.003
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发表时间：
2007-01-01
期刊：
影响因子：
3.9
通讯作者：
Katayama, Yoshiki
中科院分区：
文献类型：
--
作者：
Kang, Jeong-Hun;Jiang, Yuhua;Katayama, Yoshiki
Rho-associated kinase （Rho-kinase/ROCK/ROK）是一种丝氨酸/苏氨酸激酶，在多种细胞功能中起重要作用。camp依赖性蛋白激酶（蛋白激酶A/PKA）和蛋白激酶C （PKC）也是丝氨酸/苏氨酸激酶，直接和/或间接参与rho激酶的信号转导途径。它们具有相似的磷酸化位点基序，RXXS/T和RXS/T。本研究的目的是确定被rho激酶磷酸化的位点是否可以作为PKA和PKC的靶点，并找到rho激酶特异性的肽底物，即不被PKA和PKC磷酸化的肽底物。共检测了18个rho激酶底物被PKA和PKC磷酸化的情况。其中12个位点容易被磷酸化。这些结果意味着rho激酶底物可以作为PKA和/或PKC的良好底物。另一方面，鉴定出6种rho激酶底物对PKA和PKC的磷酸化效率为零或极低（< 20%）。动力学参数（k -m和k(cat)）表明，其中两种肽可以作为rho激酶磷酸化的特异性底物。(c) 2006 Elsevier Masson SAS。版权所有。
Rho-associated kinase (Rho-kinase/ROCK/ROK) is a serine/threonine kinase and plays an important role in various cellular functions. The cAMP-dependent protein kinase (protein kinase A/PKA) and protein kinase C (PKC) are also serine/threonine kinases, and directly and/or indirectly take part in the signal transduction pathways of Rho-kinase. They have similar phosphorylation site motifs, RXXS/T and RXS/T. The purpose of this study was to identify whether sites phosphorylated by Rho-kinase could be targets for PKA and PKC and to find peptide substrates that are specific to Rho-kinase, i.e., with no phosphorylation by PKA and PKC. A total of 18 substrates for Rho-kinase were tested for phosphorylation by PKA and PKC. Twelve of these sites were easily phosphorylated. These results mean that Rho-kinase substrates can be good substrates for PKA and/or PKC. On the other hand, six Rho-kinase substrates showing no or very low phosphorylation efficiency (< 20%) for PKA and PKC were identified. Kinetic parameters (K-m and k(cat)) showed that two of these peptides could be useful as substrates specific to Rho-kinase phosphorylation. (c) 2006 Elsevier Masson SAS. All rights reserved.