Regulation of mRNA export by nutritional status in fission yeast.
We have isolated a mutation in nup184(nup184-1) that is synthetically lethal with the mRNA export defective rae1-167 mutation in Schizosaccharomyces pombe. The consequence of the synthetic lethality is a defect in mRNA export. The predicted Nup184p is similar to Nup188p of Saccharomyces cerevisiae, and a Nup184p-GFP fusion localizes to the nuclear periphery in a punctate pattern. The Deltanup184 null mutant is viable and also is synthetically lethal with rae1-167. In a rae1(+) background, both the nup184-1 and Deltanup184 mutations confer sensitivity to growth in nutrient-rich medium (YES) that is accompanied by nuclear poly(A)+ RNA accumulation. Removal of the cAMP-dependent protein kinase, Pka1p, relieved the growth and mRNA export defects of nup184 mutants when grown in nutrient-rich medium. The activation of Pka1p is necessary, but not sufficient, to cause the severe poly(A)+ RNA export defects when nup184 mutant cells are incubated in YES, suggesting nutritional status can also regulate poly(A)+ RNA export. Our results suggest that the regulation of poly(A)+ RNA export by Pka1p kinase appears to be indirect, via a translation-dependent step, but post-translationally in response to YES.
Whalen
W A
WA
Basic Sciences Laboratory, National Cancer Institute, Bethesda, Maryland 20892, USA.
Yoon
J H
JH
Shen
R
R
Dhar
R
R
D002467:Cell Nucleus / Q000378:metabolism / Q000648:ultrastructure; D003470:Culture Media; D000242:Cyclic AMP / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D005804:Genes, Lethal; D005838:Genotype; D008954:Models, Biological; D016296:Mutagenesis; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000378:metabolism*; D012568:Schizosaccharomyces / Q000235:genetics*; D013696:Temperature
D003470:Culture Media; D005656:Fungal Proteins; D012333:RNA, Messenger; D000242:Cyclic AMP