title: Involvement of fission yeast Pdc2 in RNA degradation and P-body function.
abstract: In this study we identified Pdc2, the fission yeast ortholog of human Pat1b protein, which forms a complex with Lsm1-7 and plays a role in coupling deadenylation and decapping. The involvement of Pdc2 in RNA degradation and P-body function was also determined. We found that Pdc2 interacts with Dcp2 and is required for decapping in vivo. Although not absolutely essential for P-body assembly, overexpression of Pdc2 enhanced P-body formation even in the absence of Pdc1, the fission yeast functional homolog of human Edc4 protein, indicating that Pdc2 also plays a role in P-body formation. Intriguingly, in the absence of Pdc2, Lsm1 was found to accumulate in the nucleus, suggesting that Pdc2 shuttling between nucleus and cytoplasm plays a role in decreasing the nuclear concentration of Lsm1 to increase Lsm1 in the cytoplasm. Furthermore, unlike other components of P-bodies, the deadenylase Ccr4 did not accumulate in P-bodies in cells growing under favorable conditions and was only recruited to P-bodies after deprivation of glucose in a Pdc2-Lsm1-dependent manner, indicating a function of Pdc2 in cellular response to environmental stress. In supporting this idea,pdc2mutants are defective in recovery from glucose starvation with a much longer time to re-enter the cell cycle. In keeping with the notion that Pat1 is a nucleocytoplasmic protein, functioning also in the nucleus, we found that Pdc2 physically and genetically interacts with the nuclear 5'-3' exonuclease Dhp1. A function of Pdc2-Lsm1, in concert with Dhp1, regulating RNA by promoting its decapping/destruction in the nucleus was suggested.
authors.affiliation: Institute of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli County 350, Taiwan, Republic of China.
authors.forename: Chun-Yu
authors.initials: CY
authors.lastname: Wang
authors.affiliation: Institute of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli County 350, Taiwan, Republic of China.
authors.forename: Yi-Ting
authors.initials: YT
authors.lastname: Wang
authors.affiliation: Institute of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli County 350, Taiwan, Republic of China.
authors.forename: Wan-Yi
authors.initials: WY
authors.lastname: Hsiao
authors.affiliation: Institute of Molecular and Genomic Medicine, National Health Research Institutes, Miaoli County 350, Taiwan, Republic of China.
authors.forename: Shao-Win
authors.initials: SW
authors.lastname: Wang
mesh_terms: D021581:Active Transport, Cell Nucleus; D001483:Base Sequence; D002453:Cell Cycle / Q000235:genetics; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism; D003593:Cytoplasm / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D005095:Exoribonucleases / Q000235:genetics* / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D005947:Glucose / Q000172:deficiency / Q000494:pharmacology; D006801:Humans; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D011767:Pyruvate Decarboxylase / Q000235:genetics* / Q000378:metabolism; D039381:RNA Cap-Binding Proteins / Q000235:genetics / Q000378:metabolism; D020871:RNA Stability; D012331:RNA, Fungal / Q000235:genetics* / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D012568:Schizosaccharomyces / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; D005095:Exoribonucleases; D005656:Fungal Proteins; D005947:Glucose; D017346:Protein Serine-Threonine Kinases; D011767:Pyruvate Decarboxylase; D039381:RNA Cap-Binding Proteins; D012331:RNA, Fungal; D016601:RNA-Binding Proteins; D029702:Schizosaccharomyces pombe Proteins; D014157:Transcription Factors; C519160:Ccr4 protein, S pombe; C508496:Dcp2 protein, S pombe; C526510:PATL1 protein, human; C087019:ran1 protein, S pombe; C087281:dhp1 protein, S pombe
keywords: P-bodies; decapping; fission yeast