The stress-activated MAP kinase Sty1/Spc1 and a 3'-regulatory element mediate UV-induced expression of the uvi15(+) gene at the post-transcriptional level.
Exposure of Schizosaccharomyces pombe cells to UV light results in increased uvi15(+) gene expression at both the mRNA and protein levels, leading to elevated cell survival. This UV-induced expression of the uvi15(+) gene was reduced in Deltasty1 and Deltawis1 cells lacking the stress-activated protein kinase pathway, but not in DNA damage checkpoint mutants. To further understand the cellular mechanisms responsible for this UV-induced expression, the transcription rate and mRNA half-life were investigated. Transcription run-on assays revealed that the rate of uvi15(+) transcription was increased 1.8-fold regardless of Sty1 when cells were UV irradiated. The half-life of uvi15(+) mRNA was also increased 1.5-fold after UV irradiation, but it was decreased in the Deltasty1 background for both basal and UV-induced mRNAs, indicating that the stress-activated MAPK cascade can mediate UV-induced gene expression by increasing mRNA half-life. Deletion analyses identified a 54 nt element downstream of the distal poly(A) site, which was involved in the increased half-life of uvi15(+) mRNA. These results suggest that both Sty1 and the 3'-regulatory element regulate UV-induced expression of the uvi15(+) gene at the post-transcriptional level.
Kim
M
M
School of Biological Sciences, College of Natural Sciences, Seoul National University, Seoul 151-742, Republic of Korea.
Lee
W
W
Park
J
J
Kim
J B
JB
Jang
Y K
YK
Seong
R H
RH
Choe
S Y
SY
Park
S D
SD
D020413:3' Untranslated Regions / Q000235:genetics; D001483:Base Sequence; D004249:DNA Damage / Q000235:genetics / Q000528:radiation effects; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D017353:Gene Deletion; D015966:Gene Expression Regulation, Fungal / Q000528:radiation effects*; D005800:Genes, Fungal / Q000235:genetics*; D006207:Half-Life; D007700:Kinetics; D020935:MAP Kinase Signaling System / Q000528:radiation effects; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism*; D011061:Poly A / Q000235:genetics; D020871:RNA Stability / Q000528:radiation effects; D012331:RNA, Fungal / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics*; D012568:Schizosaccharomyces / Q000201:enzymology / Q000235:genetics / Q000528:radiation effects*; D029702:Schizosaccharomyces pombe Proteins; D014158:Transcription, Genetic / Q000235:genetics / Q000528:radiation effects; D014466:Ultraviolet Rays; D015854:Up-Regulation / Q000235:genetics / Q000528:radiation effects
D020413:3' Untranslated Regions; D005656:Fungal Proteins; D012331:RNA, Fungal; D012333:RNA, Messenger; D029702:Schizosaccharomyces pombe Proteins; D011061:Poly A; D020928:Mitogen-Activated Protein Kinases; C095409:sty1 protein, S pombe