Korean Journal of Microbiology (미생물학회지)

The Microbiological Society of Korea (한국미생물학회)
권호 표지

Effects of spTho1 Deletion and Over-Expression on mRNA Export in Fission Yeast

분열효모에서 spTho1 유전자의 결실과 과발현이 생장 및 mRNA Export에 미치는 영향

  • Cho, Ye-Seul (Basic Science Research Institute, School of Biological Science and Chemistry, College of Natural Sciences, Sungshin Women's University) ;
  • Yoon, Jin-Ho (Basic Science Research Institute, School of Biological Science and Chemistry, College of Natural Sciences, Sungshin Women's University)
  • 조예슬 (성신여자대학교 자연과학대학 생명과학.화학부 및 기초과학연구소) ;
  • 윤진호 (성신여자대학교 자연과학대학 생명과학.화학부 및 기초과학연구소)
  • Received : 2010.11.29
  • Accepted : 2010.12.17
  • Published : 2010.12.31
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Abstract

Tho1 is a RNA-binding protein that assembles co-transcriptionally onto the nascent mRNA and is thought to be involved in mRNP biogenesis and mature mRNA export to cytoplasm in budding yeast. In fission yeast Schizosaccharomyces pombe, a homologue of THO1 (spTho1) was identified based on sequence alignment. A deletion mutant in a diploid strain was constructed by replacing one of spTho1-coding region with an ura4+ gene using one-step gene disruption method. Tetrad analysis showed that the spTho1 was not essential for growth. The spTho1 mutant did not show any defects of bulk mRNA export. However, over-expression of spTho1 from strong nmt1 promoter caused the growth defects and accumulation of poly(A)$^+$ RNA in the nucleus. These results suggest that spTho1 is involved in mRNA export from the nucleus to cytoplasm though it is not essential.

출아효모 Saccharomyces cerevisiae에서 RNA-binding 단백질인 Tho1은 mRNA가 전사되는 동안 초기 mRNA에 결합하여 mRNP 생성과 성숙한 mRNA의 핵에서 세포질로의 방출에 관여하는 것으로 여겨진다. 분열효모 Schizosaccharomyces pombe에서도 Tho1과 유사한 단백질을 암호화하는 유전자(spTho1로 명명)를 찾아 그 특성을 조사하였다. 이배체 S.pombe 균주에 하나의 spTho1 유전자만을 결실시킨 후 4분체분석을 수행한 결과, 이 유전자는 생장에 반드시 필요하지 않았다. 또한 spTho1 결실 돌연변이는 mRNA의 핵에서 세포질로의 방출도 정상적으로 보였다. 그러나 티아민에 의해 발현이 조절되는 강력한 프로모터를 이용하여 spTho1를 과발현시키면, 세포의 생장이 억제되었으며 $poly(A)^+$ RNA가 핵 안에 축적되었다. 이와 같은 결과들은 spTho1 유전자가 필수적이지는 않지만 mRNA의 핵에서 세포질로의 방출에 관여하고 있음을 시사한다.

Keywords

References

  1. Alfa, C., P. Fantes, J. Hyams, M. Mcleod, and E. Warbrick. 1993. Experiments with Fission Yeast. Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, N.Y., USA.
  2. Chavez, S. and A. Aguilera. 1997. The yeast HPR1 gene has a functional role in transcriptional elongation that uncovers a novel source of genome instability. Genes Dev. 11, 3459-3470. https://doi.org/10.1101/gad.11.24.3459
  3. Chavez, S., T. Beilharz, A.G. Rondon, H. Erdjument-Bromage, P. Tempst, J.Q. Svejstrup, T. Lithgow, and A. Aguilera. 2000. A protein complex containing Tho2, Hpr1, Mft1 and a novel protein, Thp2, connects transcription elongation with mitotic recombination in Saccharomyces cerevisiae. EMBO J. 19, 5824-5834. https://doi.org/10.1093/emboj/19.21.5824
  4. Dufu, K., M.J. Livingstone, J. Seebacher, S.P. Gygi, S.A. Wilson, and R. Reed. 2010. ATP is required for interactions between UAP56 and two conserved mRNA export proteins, Aly and CIP29, to assemble the TREX complex. Genes Dev. 24, 2043-2053. https://doi.org/10.1101/gad.1898610
  5. Fasken, M.B. and A.H. Corbett. 2009. Mechanisms of nuclear mRNA quality control. RNA Biol. 6, 237-241. https://doi.org/10.4161/rna.6.3.8330
  6. Forsburg, S.L. 1993 Comparison of Schizosaccharomyces pombe expression systems. Nucleic Acids Res. 21, 2955-2956. https://doi.org/10.1093/nar/21.12.2955
  7. Hedges, S.B. 2002. The origin and evolution of model organisms. Nat. Rev. Genet. 3, 838-849. https://doi.org/10.1038/nrg929
  8. Jimeno, S., R. Luna, M. Garcia-Rubio, and A. Aguilera. 2006. Tho1, a novel hnRNP, and Sub2 provide alternative pathways for mRNP biogenesis in yeast THO mutants. Mol. Cell. Biol. 26, 4387-4398. https://doi.org/10.1128/MCB.00234-06
  9. Jimeno, S., A.G. Rondón, R. Luna, and A. Aguilera. 2002. The yeast THO complex and mRNA export factors link RNA metabolism with transcription and genome instability. EMBO J. 21, 3526-3355. https://doi.org/10.1093/emboj/cdf335
  10. Kohler, A. and E. Hurt. 2007. Exporting RNA from the nucleus to the cytoplasm. Nat. Rev. Mol. Cell Biol. 8, 761-773. https://doi.org/10.1038/nrm2255
  11. Libri, D., K. Dower, J. Boulay, R. Thomsen, M. Rosbash, and T.H. Jensen. 2002. Interactions between mRNA export commitment, 3'-end quality control, and nuclear degradation. Mol. Cell. Biol. 22, 8254-8266. https://doi.org/10.1128/MCB.22.23.8254-8266.2002
  12. Maundrell, K. 1993. Thiamine-repressible expression vectors pREP and pRIP for fission yeast. Gene 123, 127-130. https://doi.org/10.1016/0378-1119(93)90551-D
  13. Moreno, S., A. Klar, and P. Nurse. 1991. Molecular genetic analysis of fission yeast Schizosaccharomyces pombe. Methods Enzymol. 194, 795-823. https://doi.org/10.1016/0076-6879(91)94059-L
  14. Piruat, J.I. and A. Aguilera. 1998. A novel yeast gene, THO2, is involved in RNA pol II transcription and provides new evidence for transcriptional elongation-associated recombination. EMBO J. 17, 4859-4872. https://doi.org/10.1093/emboj/17.16.4859
  15. Rondon, A.G., S. Jimeno, and A. Aguilera. 2010. The interface between transcription and mRNP export: From THO to THSC/TREX-2. Biochim. Biophys. Acta. 1799, 533-538. https://doi.org/10.1016/j.bbagrm.2010.06.002
  16. Saguez, C., J.R. Olesen, and T.H. Jensen. 2005. Formation of export-competent mRNP: escaping nuclear destruction. Curr. Opin. Cell Biol. 17, 287-293. https://doi.org/10.1016/j.ceb.2005.04.009
  17. Strasser, K., S. Masuda, P. Mason, J. Pfannstiel, M. Oppizzi, S. Rodriguez-Navarro, A.G. Rondon, A. Aguilera, K. Struhl, R. Reed, and E. Hurt. 2002. TREX is a conserved complex coupling transcription with messenger RNA export. Nature 417, 304-308. https://doi.org/10.1038/nature746