Arginine Changes the Conformation of the Arginine Attenuator Peptide Relative to the Ribosome Tunnel

JOURNAL OF MOLECULAR BIOLOGY

卷:416

Article

Wu, Cheng¹  Wei, Jiajie¹  Lin, Pen-Jen²  Tu, Liwei³  Deutsch, Carol³  Johnson, Arthur E.^2,4,5  Sachs, Matthew S.¹ 

[1] Texas A&M Univ, Dept Biol, College Stn, TX 77843 USA

[2] Texas A&M Hlth Sci Ctr, Dept Mol & Cellular Med, College Stn, TX 77843 USA

[3] Univ Penn, Dept Physiol, Philadelphia, PA 19104 USA

[4] Texas A&M Univ, Dept Biochem & Biophys, College Stn, TX 77843 USA

[5] Texas A&M Univ, Dept Chem, College Stn, TX 77843 USA

关键词: translational regulation;    nascent peptide;    photocross-linking;    upstream open reading frame;    ribosome exit tunnel;   

DOI  :  10.1016/j.jmb.2011.12.064

来源: Elsevier

【 摘 要 】

The fungal arginine attenuator peptide (AAP) is a regulatory peptide that controls ribosome function. As a nascent peptide within the ribosome exit tunnel, it acts to stall ribosomes in response to arginine (Arg). We used three approaches to probe the molecular basis for stalling. First, PEGylation assays revealed that the AAP did not undergo overall compaction in the tunnel in response to Arg. Second, site-specific photocross-linking showed that Arg altered the conformation of the wild-type AAP, but not of nonfunctional mutants, with respect to the tunnel. Third, using time-resolved spectral measurements with a fluorescent probe placed in the nascent AAP, we detected sequence-specific changes in the disposition of the AAP near the peptidyltransferase center in response to Arg. These data provide evidence that an Arg-induced change in AAP conformation and/or environment in the ribosome tunnel is important for stalling. (C) 2012 Elsevier Ltd. All rights reserved.

【 授权许可】

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