Alternative translation start sites are conserved in eukaryotic genomes.

ABSTRACT: Alternative start AUG codons within a single transcript can contribute to diversity of the proteome; however, their functional significance remains controversial. Here, we provide comparative genomics evidence that alternative start codons are under negative selection in vertebrates, insects and yeast. In genes where the annotated start codon (sAUG) resides within the suboptimal nucleotide context, the downstream in-frame AUG codons (dAUG) among the first ∼30 codon sites are significantly more conserved between species than in genes where the sAUG resides within the optimal context. Proteomics data show that this difference is not an annotation artifact and that dAUGs are in fact under selection as alternative start sites. The key optimal, and sometimes suboptimal, context-determining nucl

SUBMITTER: Bazykin GA 

PROVIDER: S-EPMC3025576 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature