Cold induces stress-activated protein kinase-mediated response in the fission yeast Schizosaccharomyces pombe.
In the fission yeast Schizosaccharomyces pombe the Wak1p/Win1p-Wis1p-Sty1p stress-activated protein kinase (SAPK) pathway relays environmental signals to the transcriptional machinery and modulates gene expression via a cascade of protein phosphorylation. Cells of S. pombe subjected to cold shock (transfer from 28 degrees C to 15 degrees C) transiently activated the Sty1p mitogen-activated protein kinase (MAPK) by phosphorylation. Induction of this response was completely abolished in cells disrupted in the upstream response regulator Mcs4p. The cold-triggered Sty1p activation was partially dependent on Wak1p MAPKKK and fully dependent on Wis1p MAPKK suggesting that the signal transmission follows a branched pathway, with the redundant MAPKKK Win1p as alternative transducer to Wis1p, which subsequently activates the effector Sty1p MAPK. Also, the bZIP transcription factor Atf1p became phosphorylated in a Sty1p-dependent way during the cold shock and this phosphorylation was found responsible for the increased expression of gpd1+, ctt1+, tps1+ and ntp1+ genes. Strains deleted in transcription factors Atf1p or Pcr1p were unable to grow upon incubation at low temperature whereas those disrupted in any member of the SAPK pathway were able to do so. These data reveal that S. pombe responds to cold by inducing the SAPK pathway. However, such activation is dispensable for yeast growth in cold conditions, supporting that the presence of Atf1/Pcr1 heterodimers, rather than an operative SAPK pathway, is critical to ensure yeast growth at low temperature by an as yet undefined mechanism.
Soto
Teresa
T
Departamento de Genética y Microbiología, Facultad de Biología, Universidad de Murcia, Spain.
Beltrán
Francisco F
FF
Paredes
Vanessa
V
Madrid
Marisa
M
Millar
Jonathan B A
JB
Vicente-Soler
Jero
J
Cansado
José
J
Gacto
Mariano
M
D051697:Activating Transcription Factor 1; D051696:Activating Transcription Factors; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D003080:Cold Temperature; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004789:Enzyme Activation; D015966:Gene Expression Regulation, Fungal; D005964:Glucosyltransferases / Q000235:genetics; D020930:MAP Kinase Kinase Kinases / Q000235:genetics / Q000378:metabolism*; D020929:Mitogen-Activated Protein Kinase Kinases / Q000235:genetics / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics; D010766:Phosphorylation; D012568:Schizosaccharomyces / Q000502:physiology*; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
D051697:Activating Transcription Factor 1; D051696:Activating Transcription Factors; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; C105788:Mcs4 protein, S pombe; C097701:Pcr1 protein, S pombe; D029702:Schizosaccharomyces pombe Proteins; D014157:Transcription Factors; D005964:Glucosyltransferases; C023180:trehalose-6-phosphate synthase; D020928:Mitogen-Activated Protein Kinases; C095409:sty1 protein, S pombe; D020930:MAP Kinase Kinase Kinases; C109170:win1 protein, S pombe; C109169:wis4 protein, S pombe; D020929:Mitogen-Activated Protein Kinase Kinases; C072068:wis1 protein, S pombe; C464880:Ntp1p protein, S pombe; D010744:Phosphoric Monoester Hydrolases