Translational efficiency of redundant ACG initiator codons is enhanced by a favorable sequence context and remedial initiation

Shun Jia Chen, Chou Yuan Ko, Chih Wei Yen, Chien Chia Wang

Research output: Contribution to journalArticlepeer-review

16 Scopus citations

Abstract

Earlier studies showed that the redundancy of ACG initiation codons enhanced the efficiency of translation initiation by 3- to 6-fold. Evidence presented here shows that this "redundancy effect" can be attributed to a favorable sequence context and, to a lesser extent, remedial initiation. In the case of redundant ACG initiator codons, the second ACG not only acts as a remedial initiation site for scanning ribosomes that skip the first ACG but also enhances the activity of the preceding initiator by providing a preferable "A" at its relative +4 position. Hence, non-successive ACG codons can be as effective as successive ACG codons in initiation, if positioned within a similar context. In contrast, redundant GUG initiation codons (GUG/GUG) bear an unfavorable "G" nucleotide at both the +4 and -3 positions relative to the first and second GUGs, respectively, such that redundant GUG codons act more poorly as translation initiation sites than does a single GUG with a favorable "A" nucleotide in the +4 position (~2.5-fold). Thus, the sequence context plays a much more important role than remedial initiation in modulating the efficiency of translational initiation from redundant non-AUG codons.

Original languageEnglish
Pages (from-to)818-827
Number of pages10
JournalJournal of Biological Chemistry
Volume284
Issue number2
DOIs
StatePublished - 9 Jan 2009

Fingerprint

Dive into the research topics of 'Translational efficiency of redundant ACG initiator codons is enhanced by a favorable sequence context and remedial initiation'. Together they form a unique fingerprint.

Cite this