The control of translation is a fundamental mechanism in the regulation of gene expression. Among the cis-acting elements that play a role in translation regulation are upstream open reading frames (uORFs) and upstream AUG (uAUGs) located in the 5'UTR of mRNAs. We present here a genome-wide analysis of uAUGs and uORFs in a curated set of human and rodent mRNAs. Our study shows that the occurrence of uAUGs is suppressed more strongly than that of uORFs and that in-frame uAUGs are more strongly suppressed than out-of-frame uAUGs. A very similar pattern of uAUG/uORF frequency was also observed in mouse mRNAs. The analysis of orthologous 5'UTR sequences revealed a remarkable degree of evolutionary conservation only of those uORFs which acquired some functional activity. Our data suggest that besides leaky scanning and reinitiation, which likely occur with variable and gene-specific efficiency, the ribosome-shunt mechanism, eventually coupled to reinitiation after uORF translation, may be a widespread mode of translation regulation in eukaryotes.
|Titolo:||uAUG and uORFs in human and rodent 5'untranslated mRNAs|
MIGNONE, FLAVIO (Secondo)
|Parole Chiave:||mRNA translation; Post-transcriptional regulation; Ribosome shunting; Scanning model|
|Data di pubblicazione:||2005|
|Digital Object Identifier (DOI):||10.1016/j.gene.2004.11.041|
|Appare nelle tipologie:||01 - Articolo su periodico|