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Pervasive Translation in Mycobacterium tuberculosis

ABSTRACT: The vast majority of bacterial open reading frames (ORFs) are identified by automated prediction algorithms. However, these algorithms fail to identify ORFs that deviate from the canonical features of ORFs such as a length of >50 codons, and the presence of an upstream Shine-Dalgarno sequence. Here, we use ribosome profiling approaches to experimentally identify actively translated ORFs in Mycobacterium tuberculosis. Most of the ORFs we identify have not been previously described, indicating that the M. tuberculosis transcriptome is pervasively translated. Moreover, the newly described ORFs are predominantly short, with many encoding proteins of ≤50 amino acids. The codon usage of the newly discovered ORFs suggests that most are not undergoing purifying selection, and hence are unlikely to contribute to cell fitness. Nevertheless, we identify ~90 new ORFs, with a median length of 52 codons, that bear the hallmarks of purifying selection. Thus, our data suggest that pervasive translation of short ORFs serves as a rich source for the evolution of new functional proteins

INSTRUMENT(S): Illumina HiSeq 2500

ORGANISM(S): Mycobacterium tuberculosis

SUBMITTER: Todd Gray

PROVIDER: E-MTAB-10695 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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