Extending the Spacing between the Shine-Dalgarno Sequence and P-Site Codon Reduces the Rate of mRNA Translocation

JOURNAL OF MOLECULAR BIOLOGY

卷:432

Article

Wakabayashi, Hironao^1,2  Warnasooriya, Chandani^1,2  Ermolenko, Dmitri N.^1,2 

[1] Univ Rochester, Sch Med & Dent, Dept Biochem & Biophys, Rochester, NY 14642 USA

[2] Univ Rochester, Ctr RNA Biol, Rochester, NY 14642 USA

关键词: translation pausing;    frameshifting;    toeprinting assay;    translocation kinetics;    Forster resonance energy transfer;   

DOI  :  10.1016/j.jmb.2020.06.008

来源: Elsevier

【 摘 要 】

By forming base-pairing interactions with the 3' end of 16S rRNA, mRNA Shine-Dalgarno (SD) sequences positioned upstream of open reading frames facilitate translation initiation. During the elongation phase of protein synthesis, intragenic SD-like sequences stimulate ribosome frameshifting and may also slow down ribosome movement along mRNA. Here, we show that the length of the spacer between the SD sequence and P-site codon strongly affects the rate of ribosome translocation. Increasing the spacer length beyond 6 nt destabilizes mRNA-tRNA-ribosome interactions and results in a 5- to 10-fold reduction of the translocation rate. These observations suggest that during translation, the spacer between the SD sequence and P-site codon undergoes structural rearrangements, which slow down mRNA translocation and promote mRNA frameshifting. (C) 2020 Elsevier Ltd. All rights reserved.

【 授权许可】

Free