Expression of hsp16 in response to nucleotide depletion is regulated via the spc1 MAPK pathway in Schizosaccharomyces pombe.
A universal response to elevated temperature and other forms of physiological stress is the induction of heat shock proteins (HSPs). Hsp16 in Schizosaccharomyces pombe encodes a polypeptide of predicted molecular weight 16 kDa that belongs to the HSP20/alpha-crystallin family whose members range in size from 12 to 43 kDa. Heat shock treatment increases expression of the hsp16 gene by 64-fold in wild-type cells and 141-fold in cdc22-M45 (ribonucleotide reductase) mutant cells. Hsp16 expression is mediated by the spc1 MAPK signaling pathway through the transcription factor atf1 and in addition through the HSF pathway. Nucleotide depletion or DNA damage as occurs in cdc22-M45 mutant cells, or during hydroxyurea or camptothecin treatment, is sufficient to activate hsp16 expression through atf1. Our findings suggest a novel role for small HSPs in the stress response following nucleotide depletion and DNA damage. This extends the types of damage that are sensed by the spc1 MAPK pathway via atf1.
Taricani
L
L
Department of Biology, Bioscience Complex, Queen's University, Kingston, Ontario K7L 3N6, Canada.
Feilotter
H E
HE
Weaver
C
C
Young
P G
PG
D018797:Cell Cycle Proteins / Q000235:genetics; D018834:Chaperonin 60 / Q000235:genetics* / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal / Q000187:drug effects; D005947:Glucose / Q000494:pharmacology; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008856:Microscopy, Fluorescence; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009154:Mutation; D009584:Nitrogen / Q000494:pharmacology; D009711:Nucleotides / Q000494:pharmacology*; D012331:RNA, Fungal / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics; D012568:Schizosaccharomyces / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D029702:Schizosaccharomyces pombe Proteins; D015398:Signal Transduction / Q000187:drug effects; D020798:Two-Hybrid System Techniques
D018797:Cell Cycle Proteins; D018834:Chaperonin 60; D008164:Luminescent Proteins; D009711:Nucleotides; D012331:RNA, Fungal; D011993:Recombinant Fusion Proteins; D029702:Schizosaccharomyces pombe Proteins; C080926:cdc22 protein, S pombe; D049452:Green Fluorescent Proteins; D020928:Mitogen-Activated Protein Kinases; C095409:sty1 protein, S pombe; D005947:Glucose; D009584:Nitrogen