Functional evidence for D‐ and T‐loop interactions in tmRNA

FEBS Letters

de Smit, Maarten H.²  Kraal, Barend²  Björk, Karl²  Barends, Sharief²  Pleij, Cornelis W.A.²  Gultyaev, Alexander P.¹ 

[1] Group Theoretical Biology and Phylogenetics, Institute of Evolutionary and Ecological Sciences, Leiden University, Kaiserstraat 63, 2311 GP Leiden, The Netherlands;Department of Biochemistry, Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands

关键词: tmRNA;    Ala-tRNA synthetase;    Elongation factor Tu;    SmpB;    tRNA folding;    trans-Translation;   

DOI  :  10.1016/S0014-5793(02)02306-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

During bacterial protein synthesis, stalled ribosomes can be rescued by tmRNA, a molecule with both tRNA and mRNA features. The tRNA region of tmRNA has sequence similarity with tRNA^Ala and also has a clover-leaf structure folded similarly as in canonical tRNAs. Here we propose the L-shape of tmRNA to be stabilized by two tertiary interactions between its D- and T-loop on the basis of phylogenetic and experimental evidence. Mutational analysis clearly demonstrates a tertiary interaction between G₁₃ and U₃₄₂. Strikingly, this in evolution conserved interaction is not primarily important for tmRNA alanylation and for binding to elongation factor Tu, but especially for a proper functioning of SmpB.

【 授权许可】

Unknown