SKK4, a novel activator of stress‐activated protein kinase‐1 (SAPK1/JNK)

FEBS Letters

Cuenda, Ana²  Lawler, Sean²  Cohen, Philip²  Goedert, Michel¹ 

[1] MRC Laboratory of Molecular Biology, Hills Road, Cambridge, UK;MRC Protein Phosphorylation Unit, Department of Biochemistry, University of Dundee, Dundee DD1 4HN, UK

关键词: SAPK;    JNK;    p38;    MAP kinase;    Cytokine;    Stress;   

DOI  :  10.1016/S0014-5793(97)00990-3

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A cDNA was cloned and expressed that encodes human stress-activated protein kinase kinase-4 (SKK4), a novel MAP kinase kinase family member whose mRNA is widely expressed in human tissues. SKK4 activated SAPK1/JNK in vitro, but not SAPK2a/p38, SAPK2b/p38β, SAPK3/ERK6 or SAPK4. It appears to be the mammalian homologue of HEP, an activator of SAPK1/JNK in Drosophila. In human epithelial KB cells SKK4 and SKK1/MKK4 (another activator of SAPK1/JNK) were both activated by stressful stimuli, but only SKK4 was activated by proinflammatory cytokines. The identification of SKK4 explains why the major SAPK1/JNK activator detected in many mammalian cell extracts is chromatographically separable from SKK1/MKK4.

【 授权许可】

Unknown