Open AccessStudy of multiple fibrillarin mRNAs reveals that 3′ end formation inSchizosaccharomyces pombeis sensitive to cold shock
Author(s) -
JeanPhilippe Girard,
Jacgues Feliu,
Michèle CaizerguesFerrer,
Bruno Lapeyre
Publication year - 1993
Publication title -
nucleic acids research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 9.008
H-Index - 537
eISSN - 1362-4954
pISSN - 0305-1048
DOI - 10.1093/nar/21.8.1881
Subject(s) - biology , library science , schizosaccharomyces pombe , classics , zoology , history , genetics , computer science , mutant , gene
Fibrillarin is a nucleolar protein which is associated with small nucleolar RNAs, and is required for pre-rRNA processing. We have cloned and characterized the gene encoding fibrillarin in the fission yeast Schizosaccharomyces pombe and we have followed its expression under various conditions. Fission yeast fibrillarin is a 305 amino-acid protein which appears to be highly conserved throughout evolution. In Xenopus, human or Saccharomyces cerevisiae, a single fibrillarin mRNA is detected while, in S. pombe a single copy gene encodes different mRNAs which differ at the 3' ends. Under normal growth conditions, two mRNAs of 1.1 and 1.35 kb are detected with the 1.1 kb being the most abundant. Both the total amount and relative abundance of these two mRNAs are strongly affected by exposure to low temperature, namely the 1.1 kb mRNA almost disappears while the 1.35 kb is less markedly diminished. A new species of 3.2 kb accumulates in the cell, which contains an unusually long 3' untranslated region of 2 kb. We have found that exposure of the cells to a cold shock has a profound effect on 3' end formation in S.pombe since the transcription of several other mRNAs is also capable of skipping the normal 3' end site to terminate at a further downstream site.