p150(Glued), Dynein, and microtubules are specifically required for activation of MKK3/6 and p38 MAPKs.
To look for regulators of the mitogen-activated protein kinase (MAPK) kinase 6 (MKK6), a yeast two-hybrid screen was initiated using MKK6 as bait. p150(Glued) dynactin, a key component of the cytoplasmic dynein-dynactin motor complex, was found to specifically interact with MKK6 and its close homologue MKK3. Silencing of p150(Glued) expression by small interference RNA reduced the stimulus-induced phosphorylation of MKK3/6 and p38 MAPKs. The similar adverse effect was also seen when the cytoplasmic dynein motor was disrupted by other means. Like p150(Glued), MKK3/6 directly associate with microtubules. Disruption of microtubules prior to cell stimulation specifically inhibits the stimulus-induced phosphorylation of both MKK3/6 and p38 MAPKs. Our unexpected findings reveal a specific requirement for p150(Glued)/dynein/functional microtubules in activation of MKK3/6 and p38 MAPKs in vivo.
Cheung
Po-Yan
PY
Department of Biochemistry, Hong Kong University of Science & Technology, Clear Water Bay, Kowloon, Hong Kong, China.
Zhang
Yi
Y
Long
Jiafu
J
Lin
Shengcai
S
Zhang
Mingjie
M
Jiang
Yong
Y
Wu
Zhenguo
Z
D000072159:Dynactin Complex; D004398:Dyneins / Q000502:physiology*; D004789:Enzyme Activation; D006367:HeLa Cells; D006801:Humans; D048371:MAP Kinase Kinase 3 / Q000378:metabolism*; D048669:MAP Kinase Kinase 6 / Q000378:metabolism*; D008869:Microtubule-Associated Proteins / Q000502:physiology*; D008870:Microtubules / Q000502:physiology*; D010766:Phosphorylation; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism*
C000606360:DCTN1 protein, human; D000072159:Dynactin Complex; D008869:Microtubule-Associated Proteins; D048051:p38 Mitogen-Activated Protein Kinases; D048371:MAP Kinase Kinase 3; D048669:MAP Kinase Kinase 6; C482530:MAP2K3 protein, human; C482566:MAP2K6 protein, human; D004398:Dyneins