Structures of tRNAs with an expanded anticodon loop in the decoding center of the 30S ribosomal subunit
2007 (English)In: RNA: A publication of the RNA Society, ISSN 1355-8382, Vol. 13, no 6, 817-823 p.Article in journal (Refereed) Published
During translation, some +1 frameshift mRNA sites are decoded by frameshift suppressor tRNAs that contain an extra base in their anticodon loops. Similarly engineered tRNAs have been used to insert nonnatural amino acids into proteins. Here, we report crystal structures of two anticodon stem–loops (ASLs) from tRNAs known to facilitate +1 frameshifting bound to the 30S ribosomal subunit with their cognate mRNAs. ASLCCCG and ASLACCC (5'–3' nomenclature) form unpredicted anticodon–codon interactions where the anticodon base 34 at the wobble position contacts either the fourth codon base or the third and fourth codon bases. In addition, we report the structure of ASLACGA bound to the 30S ribosomal subunit with its cognate mRNA. The tRNA containing this ASL was previously shown to be unable to facilitate +1 frameshifting in competition with normal tRNAs (Hohsaka et al. 2001), and interestingly, it displays a normal anticodon–codon interaction. These structures show that the expanded anticodon loop of +1 frameshift promoting tRNAs are flexible enough to adopt conformations that allow three bases of the anticodon to span four bases of the mRNA. Therefore it appears that normal triplet pairing is not an absolute constraint of the decoding center.
Place, publisher, year, edition, pages
2007. Vol. 13, no 6, 817-823 p.
frameshift suppressor tRNAs, ribosome, +1 frameshift, processivity errors, anticodon stem–loop
IdentifiersURN: urn:nbn:se:uu:diva-10996DOI: 10.1261/rna.367307PubMedID: 17416634OAI: oai:DiVA.org:uu-10996DiVA: diva2:38764
Forskningen utfördes vid MRC-LMB i Cambridge.2008-01-302008-01-302010-02-22Bibliographically approved