Modulation of Escherichia coli RNase E. Action by RraAS2, a Streptomyces coelicolor Ortholog of RraA

Streptomyces coelicolor의 RraA 동족체인 RraAS2에 의한 Escherichia coli RNase E 활성조절

  • 안상미 (중앙대학교 자연과학대학 생명과학과) ;
  • 신은경 (중앙대학교 자연과학대학 생명과학과) ;
  • 염지현 (중앙대학교 자연과학대학 생명과학과) ;
  • 이강석 (중앙대학교 자연과학대학 생명과학과)
  • Published : 2008.06.30

Abstract

RraA is a recently discovered protein inhibitor that regulates the enzymatic activity of RNase E, which plays a major role in the decay and processing of RNAs in Escherichia coli. It has also been shown to regulate the activity of RNase ES, a functional Streptomyces coelicolor ortholog of RNase E, which has 36% identity to the amino-terminal region of RNase E. There are two open reading frames in S. coelicolor genome that can potentially encode proteins having more than 35.4% similarity to the amino acid sequence of RraA. DNA fragment encoding one of these RraA orthologs, designated as RraAS2 here, was amplified and cloned in to E. coli vector to test whether it has ability to regulate RNase E activity in E. coli cells. Co-expression of RraAS2 partially rescued E. coli cells over-producing RNase E from growth arrest, although not as efficiently as RraA, induced by the increased ribonucleolytic activity in the cells. The copy number of ColEl-type plasmid in these cells was also decreased by 14% compared to that in cells over-producing RNase E only, indicating the ability of RraAS2 to inhibit RNase E action on RNA I. We observed that the expression level of RraAS2 was lower than that of RraA by 4.2 folds under the same culture condition, suggesting that because of inefficient expression of RraAS2 in E. coli cells, co-expression of RraAS2 was not efficiently able to inhibit RNase E activity to the level for proper processing and decay of all RNA species that is required to restore normal cellular growth to the cells over-producing RNase E.

최근 Escherichia coli에서 RNA의 분해와 가공과정에 중추적인 역할을 하는 리보핵산 내부분해효소인 RNase E의 효소활성을 조절하는 단백질 조절자인 RraA가 밝혀졌으며, 이 단백질은 E. coli RNase E의 효소활성 부위와 36%의 유사성을 가지는, Streptomyces coelicolor RNase ES의 효소활성을 조절하는 것으로 알려져 있다. S. coelicolor의 유전체에는 RraA와 아미노산 서열이 35.4% 이상 유사한 단백질을 코딩하는 유전자가 두 개 존재하는데, 그 중 하나인 rraAS2를 클로닝하여 E. coli RNase E의 효소활성을 조절하는지를 알아보았다. 그 결과 세포내에서 RraAS2를 발현시키면 RNase E의 과발현에 의해 저해된 세포의 생장을 RraA와 같이 효과적으로는 아니지만, 어느 정도 복원시키는 것을 확인하였다. 또한 RraAS2가 발현됨으로서 RNase E의 과발현에 의해 증가된 ColE1-타입 플라스미드의 복제 수를 14% 감소시키는 것을 관찰하였다. 이러한 결과는 RraAS2가 RNase E의 RNA I분자에 대한 효소 활성을 저해하는 능력을 가지고 있음을 시사한다. 동일한 배양조건에서 E. coli 세포내에서의 RNase E에 대한 RraAS2의 상대적인 발현양이 RraA에 비해 6.2배 낮은 것을 확인하였고, 이로 인해 RraAS2가 RNase E의 과발현에 의한 세포 생장의 저해를 복원하는데 필요한 모든 RNA의 가공과 분해속도를 효과적으로 조절하지는 못한다는 것을 추론할 수 있다.

Keywords

References

  1. Apirion, D. and A.B. Lassar. 1978. A conditional lethal mutant of Escherichia coli which affects the processing of ribosomal RNA. J. Biol. Chem. 253, 1738-1742
  2. Callaghan, A.J., M.J. Marcaida, J.A. Stead, K.J. McDowall, W.G. Scott, and B.F. Luisi. 2005. Structure of Escherichia coli RNase E catalytic domain and implications for RNA turnover. Nature 437, 1187-1191 https://doi.org/10.1038/nature04084
  3. Carpousis, A.J., G.V. Houwe, C. Ehretsmann, and H.M. Krisch. 1994. Co-purification of E. coli RNase E and PNPase: Evidence for a specific association between two enzymes important in RNA processing and degradation. Cell. 76, 889-900 https://doi.org/10.1016/0092-8674(94)90363-8
  4. Condon, C., J. Rourera, D. Brechemier-Baey, and H. Putzer. 2002. Ribonuclease M5 has few, if any, mRNA substrates in Bacillus subtilis. J. Bacterial. 184, 2845-2849 https://doi.org/10.1128/JB.184.10.2845-2849.2002
  5. Feng, Y., H. Huang, J. Liao, and S.N. Cohen. 2001. Escherichia coli poly(A)-binding proteins that interact with components of degradosomes or impede RNA decay mediated by polynucleotide phosphorylase and RNase E. J. Biol. Chem. 276, 31651-31656 https://doi.org/10.1074/jbc.M102855200
  6. Gao, I., K. Lee, M. Zhao, J. Qiu, X. Zhan, A. Saxena, C.J. Moore, S.N. Cohen, and G. Georgiou. 2006. Differential modulation of E. coli mRNA abundance by inhibitory proteins that alter the composition of the degradosome. Mol. Microbiol. 61, 394-406 https://doi.org/10.1111/j.1365-2958.2006.05246.x
  7. Gurevitz, M. and D. Apirion. 1983. Interplay among processing and degradative enzymes and a precursor ribonucleic acid in the selective maturation and maintenance of ribonucleic acid molecules. Biochemistry 22, 4000-4005 https://doi.org/10.1021/bi00286a002
  8. Gurevitz, M., S.K. Jain, and D. Apirion. 1983. Identification of a precursor molecular for the RNA moiety of the processing enzyme RNase P. Proc. Natl. Acad. Sci. USA 80, 4450-4454
  9. Huang, H., J. Liao, and S.N. Cohen. 1998. Poly(A)- and poly(U)- specific RNA 3'tail shortening by E. coli ribonuclease E. Nature 391, 99-102 https://doi.org/10.1038/34219
  10. Jain, C. and J.G. Belasco. 1995. RNase E autoregulates its synthesis by controlling the degradation rate of its own mRNA in Escherichia coli: unusual sensitivity of the rne transcript to RNase E activity. Genes Dev. 9, 84-96 https://doi.org/10.1101/gad.9.1.84
  11. Kalapos, M.P., H. Paulusb, and N. Sarkara. 1997. Identification of ribosomal protein S1 as a poly(A) binding protein in Escherichia coli. Biochimie 79, 493-502 https://doi.org/10.1016/S0300-9084(97)82741-1
  12. Kim, S., H. Kim, I. Park, and Y. Lee. 1996. Mutational analysis of RNA structures and sequences postulated to affect 3' processing of M1 RNA, the RNA component of Escherichia coli RNase P. J. Biol. Chem. 271, 19330-19337 https://doi.org/10.1074/jbc.271.32.19330
  13. Lee, K., J.A. Bernstein, and S.N. Cohen. 2002. RNase G complementation of rne null mutation identifies functional interrelationships with RNase E in Escherichia coli. Mol. Microbiol. 43, 1445-1456 https://doi.org/10.1046/j.1365-2958.2002.02848.x
  14. Lee, K. and S.N. Cohen. 2003. A Streptomyces coelicolor functional orthologue of Escherichia coli RNase E shows shuffling of catalytic and PNPase-binding domains. Mol. Microbiol. 48, 349-360 https://doi.org/10.1046/j.1365-2958.2003.03435.x
  15. Lee, K., X. Zhan, J. Gao, J. Qiu, Y. Feng, R. Meganathan, S.N. Cohen, and G. Georgiou. 2003. RraA: a protein Inhibitor of RNase E activity that globally modulates RNA abundance in E. coli. Cell. 114, 623-634 https://doi.org/10.1016/j.cell.2003.08.003
  16. Leroy, A., N.F. Vanzo, S. Sousa, M. Dreyfus, and A.J. Carpousis. 2002. Function in Escherichia coli of the non-catalytic part of RNase E: role in the degradation of ribosome-free mRNA. Mol. Microbiol. 45, 1231-1243 https://doi.org/10.1046/j.1365-2958.2002.03104.x
  17. Li, Z. and M.P. Deutscher. 2002. RNase E plays an essential role in the maturation of Escherichia coli tRNA precursors. RNA 8, 97-109 https://doi.org/10.1017/S1355838202014929
  18. Li, Z., S. Pandit, and M.P. Deutscher. 1999. RNase G (CafA protein) and RNase E are both required for the 5' maturation of 16S ribosomal RNA. EMBO J. 18, 2878-2885 https://doi.org/10.1093/emboj/18.10.2878
  19. Lin-Chao, S. and S.N. Cohen. 1991. The rate of processing and degradation of antisense RNA I regulates the replication of ColE1-type plasmids in vivo. Cell. 65, 1233-1242 https://doi.org/10.1016/0092-8674(91)90018-T
  20. Lin-Chao, S., T.T. Wong, K.J. McDowall, and S.N. Cohen. 1994. Effects of nucleotide sequence on the specificity of rne-dependent and RNase E-mediated cleavages of RNA I encoded by the pBR322 plasmid J. Biol. Chem. 269, 10797-10803
  21. Liou, G.G., W.N. Jane, S.N. Cohen, N.S. Lin, and S. Lin-Chao. 2001. RNA degradosomes exist in vivo in Escherichia coli as multicomponent complexes associated with the cytoplasmic membrane via the N-terminal region of ribonuclease E. Proc. Natl. Acad. Sci. USA 98, 63-68
  22. Masse, E., F.E. Escorcia, and S. Gottesman. 2003. Coupled degradation of a small regulatory RNA and its mRNA targets in Escherichia coli. Genes Dev. 17, 2374-2383 https://doi.org/10.1101/gad.1127103
  23. McDowall, K.J. and S.N. Cohen. 1996. The N-terminal domain of the rne gene product has RNase E activity and is non-overlapping with the arginine-rich RNA-binding motif. J. Mol. Biol. 255, 349-355 https://doi.org/10.1006/jmbi.1996.0027
  24. Miczak, A., V.R. Kaberdin, C.L. Wei, and S. Lin-Chao. 1996. Proteins associated with RNase E in a multicomponent ribonucleolytic complex. Proc. Natl. Acad. Sci. USA 93, 3865-3869
  25. Morita, T., H. Kawamoto, T. Mizota, T. Inada, and H. Aiba. 2004. Enolase in the RNA degradosome plays a crucial role in the rapid decay of glucose transporter mRNA in the response to phosphor-sugar stress in Escherichia coli. Mol. Microbiol. 54, 1063-1075 https://doi.org/10.1111/j.1365-2958.2004.04329.x
  26. Morita, T., Y. Mochizuki, and H. Aiba. 2006. Translational repression is sufficient for gene silencing by bacterial small non-coding RNAs in the absence of mRNA destruction. Proc. Natl. Acad. Sci. USA 103, 4858-4863
  27. Mudd, E.A. and C.F. Higgins. 1993. Escherichia coli endoribonuclease RNase E : autoregulation of expression and site-specific cleavage of mRNA. Mol. Microbiol. 9, 557-568 https://doi.org/10.1111/j.1365-2958.1993.tb01716.x
  28. Py, B., C.F. Higgins, H.M. Krisch, and A.J. Carpousis. 1996. A DEAD-box RNA helicase in the Escherichia coli RNA degradosome. Nature 381, 169-172 https://doi.org/10.1038/381169a0
  29. Taraseviciene, L., G.R. Bjork, and B.E. Uhlin. 1995. Evidence for an RNA binding region in the Escherichia coli processing endoribonuclease RNase E. J. Biol. Chem. 270, 26391-26398 https://doi.org/10.1074/jbc.270.44.26391
  30. Vanzo, N.F., Y.S. Li, B. Py, E. Blum, C.F. Higgins, L.C. Raynal, H.M. Krisch, and A.J. Carpousis. 1998. Ribonuclease E organizes the protein interactions in the Escherichia coli RNA degradosome. Genes Dev. 12, 2770-2781 https://doi.org/10.1101/gad.12.17.2770
  31. Walsh, A.P., M.R. Tock, M.H. Mallen, V.R. Kaberdin, A.V. Gabain, and K.J. McDowall. 2001. Cleavage of poly (A) tails on the 3'-end of RNA by ribonuclease E of Escherichia coli. Nucleic Acids Res. 29, 1864-1871 https://doi.org/10.1093/nar/29.9.1864
  32. Yeom, J.H. and K. Lee. 2006. RraA rescues Escherichia coli cells over-producing RNase E from growth arrest by modulating the ribonucleolytic activity. Biochem. Biophys. Res. Commun. 345, 1372-1376 https://doi.org/10.1016/j.bbrc.2006.05.018
  33. Yeom, J.H., E. Shin, H. Go, S. Sim, and K. Lee. 2008. Functional implications of the conserved action of regulators of ribonuclease activity. J. Microbiol. Biotechnol. Article in press
  34. Yeom, J.H., H. Go, E. Shin, H.L. Kim, S.H. Han, C.J. Moore, J. Bae, and K. Lee. 2008. Inhibitory effects of RraA and RraB on RNAse E-related enzymes imply conserved functions in the regulated enzymatic cleavage of RNA. FEMS Microbiol. Lett. Article in press