A complex gene regulatory mechanism that operates at the nexus of multiple RNA processing decisions.
Expression of crs1 pre-mRNA, encoding a meiotic cyclin, is blocked in actively growing fission yeast cells by a multifaceted mechanism. The most striking feature is that in vegetative cells, crs1 transcripts are continuously synthesized but are targeted for degradation rather than splicing and polyadenylation. Turnover of crs1 RNA requires the exosome, as do previously described nuclear surveillance and silencing mechanisms, but does not involve a noncanonical poly(A) polymerase. Instead, crs1 transcripts are targeted for destruction by a factor previously implicated in turnover of meiotic RNAs in growing cells. Like exosome mutants, mmi1 mutants splice and polyadenylate vegetative crs1 transcripts. Two regulatory elements are located at the 3' end of the crs1 gene, consistent with the increased accumulation of spliced RNA in polyadenylation factor mutants. This highly integrated regulatory strategy may ensure a rapid response to adverse conditions, thereby guaranteeing survival.
McPheeters
David S
DS
Center for RNA Molecular Biology and Department of Molecular Biology & Microbiology, Case Western Reserve University, School of Medicine, 10900 Euclid Avenue, Cleveland, Ohio 44106-4960, USA.
Cremona
Nicole
N
Sunder
Sham
S
Chen
Huei-Mei
HM
Averbeck
Nicole
N
Leatherwood
Janet
J
Wise
Jo Ann
JA
D016213:Cyclins / Q000096:biosynthesis*; D055354:Exosomes / Q000378:metabolism; D005656:Fungal Proteins / Q000096:biosynthesis*; D015966:Gene Expression Regulation, Fungal; D008954:Models, Biological; D011062:Polynucleotide Adenylyltransferase / Q000378:metabolism; D012322:RNA Precursors / Q000378:metabolism; D012326:RNA Splicing; D020871:RNA Stability; D012331:RNA, Fungal / Q000378:metabolism*; D012568:Schizosaccharomyces / Q000502:physiology*; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism; D039221:mRNA Cleavage and Polyadenylation Factors / Q000235:genetics / Q000378:metabolism
D016213:Cyclins; D005656:Fungal Proteins; C512176:Mmi1 protein, S pombe; D012322:RNA Precursors; D012331:RNA, Fungal; D029702:Schizosaccharomyces pombe Proteins; D039221:mRNA Cleavage and Polyadenylation Factors; D011062:Polynucleotide Adenylyltransferase