Liu Y, Zhang S, Klessig D F
Waksman Institute and The Department of Molecular Biology and Biochemistry, Rutgers, The State University of New Jersey, Piscataway 08854-8020, USA.
Mol Plant Microbe Interact. 2000 Jan;13(1):118-24. doi: 10.1094/MPMI.2000.13.1.118.
A tobacco MAP kinase termed SIPK (Salicylic acid-Induced Protein Kinase) is activated in response to a variety of stress signals, including pathogen attack and wounding (S. Zhang and D.F. Klessig, Proc. Natl. Acad. Sci. USA 95:7225-7230, 1998; S. Zhang and D.F. Klessig, Proc. Natl. Acad. Sci. USA 95:7433-7438, 1998). Using the yeast two-hybrid system, we have identified a gene encoding a protein that interacts with SIPK but not the wounding induced protein kinase (WIPK), which is another tobacco MAP kinase. Sequence analysis indicated that this SIPK-interacting protein is a member of the MAP kinase kinase family; thus, it was named SIPK kinase (SIPKK). Co-immunoprecipitation experiments demonstrated that SIPKK and SIPK interact in vitro. Consistent with its putative function as a kinase, SIPKK phosphorylated myelin basic protein in vitro. Interestingly, SIPKK was induced at the mRNA level after Tobacco mosaic virus (TMV) infection or wounding, albeit with kinetics that are too slow to account for the activation of SIPK following these stimuli.
一种名为SIPK（水杨酸诱导蛋白激酶）的烟草促分裂原活化蛋白激酶（MAP激酶）可被多种应激信号激活，包括病原体侵袭和创伤（张S.和克莱西格D.F.，《美国国家科学院院刊》95:7225 - 7230，1998；张S.和克莱西格D.F.，《美国国家科学院院刊》95:7433 - 7438，1998）。利用酵母双杂交系统，我们鉴定出一个编码与SIPK相互作用但不与创伤诱导蛋白激酶（WIPK，另一种烟草MAP激酶）相互作用的蛋白的基因。序列分析表明，这种与SIPK相互作用的蛋白是MAP激酶激酶家族的成员；因此，它被命名为SIPK激酶（SIPKK）。免疫共沉淀实验证明SIPKK和SIPK在体外相互作用。与其作为激酶的假定功能一致，SIPKK在体外可磷酸化髓鞘碱性蛋白。有趣的是，烟草花叶病毒（TMV）感染或创伤后，SIPKK在mRNA水平上被诱导，尽管其动力学过程过于缓慢，无法解释这些刺激后SIPK的激活。
