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研究発表を行った学会；
・第４０回日本発生生物学会・第５９回日本細胞生物学会　合同大会、2007年 5月28~30日(福岡)

タイトル；The fission yeast ptr5+ gene required for nuclear mRNA export encodes the nucleoporin Nup85p.
発表者；　渡邉　常義　氏
　　　（熊本大学大学院自然科学研究科理学専攻生命科学コース　谷研究室）
Abstract；
To analyze the mechanisms of mRNA export from the nucleus, we have isolated ptr [poly(A)+RNA transport] 1 to 11, which accumulate poly(A)+RNA in the nucleus at the nonpermissive temperature in fission yeast Schizosaccharomyces pombe.
The ptr5-1 mutant rapidly accumulates poly(A)+RNA in the nucleus after shifting to the nonpermissive temperature and shows dot-like or ring-like signals at the nuclear periphery. We cloned the ptr5+ gene and found that it encodes the nucleoporin Nup85p. The ptr5-1 mutant has a single nucleotide mutation (496G to A), resulting in replacement of 166E with K. To examine whether protein transport is also detective in ptr5-1 at the nonpermissive temperature, we performed protein transport assay using a NLS-NES-GFP fusion protein as a reporter. The results showed that ptr5-1 has no defects in protein transport, suggesting that the export block is specific for mRNA in ptr5-1. Thus, Ptr5p/Nup85p seems to be specifically involved in mRNA export. Then, to examine functional interaction with known mRNA export factors, we constructed a double mutant with ptr5-1 and rae1-167, of which the wild type gene encodes an essential mRNA export factor Rae1p. The ptr5-1 rae1-167 double mutant showed synthetic lethality, suggesting that Ptr5p/Nup85p is involved in nuclear mRNA export through Rae1p.