TpMRK regulates cell division of Tetrahymena in response to oxidative stress.
TpMRK was identified as a stress-responsive mitogen activated protein kinase (MAPK)-related kinase and has been shown to play a critical role in the stress signalling in Tetrahymena cells. Here, we found that the mRNA expression of TpMRK was correlated with cell division of Tetrahymena with decreased expression occurring in cells prior to entering synchronous cell division induced by heat treatment. Notably, cell division was delayed with a lower division index of 40% after exposure to hydrogen peroxide while 85% of cells underwent cell division synchronously at 75 min after heat treatment without the oxidative exposure. Furthermore, inactivation of TpMRK signalling by p38 MAPK inhibitor SB203580 or MEK inhibitor PD 98059 partially derepressed cell division induced by hydrogen peroxide. Our data suggest that oxidative stimuli might cause aberration of synchronous cell division of Tetrahymena through activating the TpMRK cascade.
Li
Wenzhou
W
State Key Laboratory of Genetic Engineering, Institute of Genetics, Fudan University School of Life Sciences, Shanghai 200433, PR China.
Zhang
Siwei
S
Numata
Osamu
O
Nozawa
Yoshinori
Y
Wang
Shulin
S
D000818:Animals; D002455:Cell Division / Q000502:physiology*; D005786:Gene Expression Regulation; D020935:MAP Kinase Signaling System / Q000502:physiology*; D020929:Mitogen-Activated Protein Kinase Kinases / Q000037:antagonists & inhibitors / Q000502:physiology*; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors; D018384:Oxidative Stress / Q000502:physiology*; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013769:Tetrahymena pyriformis / Q000166:cytology / Q000201:enzymology* / Q000235:genetics
D012333:RNA, Messenger; D020928:Mitogen-Activated Protein Kinases; D020929:Mitogen-Activated Protein Kinase Kinases