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bioRxiv · 10.1101/660928

Non-coding RNAs control metabolic state in mycobacteria

Ramesh, A.·Mehta, D.·K, A.·A, A.·Gupta, R.
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Abstract

Non-coding RNAs play pivotal roles in bacterial signaling. However, RNAs from certain phyla (specially high-GC actinobacteria) remain elusive. Here, by revamping existing approaches we discover a family of structurally conserved RNAs in actinobacteria. These RNAs function by the recruiting ANTAR proteins to select transcripts; regulating them via translational repression. By overlapping with ORF start sites, these RNAs provide mechanisms by which even leader-less transcripts are regulated. In mycobacteria, transcripts marked by ANTAR-target RNAs are few but encode important redox enzymes especially involved in lipid metabolism. Notably, the cellular response to ANTAR-regulation is hierarchical, wherein immediate metabolic changes induced by ANTAR-RNA binding are amplified through a global transcriptomic response. This includes several genes from oxidative/reductive pathways; ultimately switching cells towards reductive metabolism. This discovery of ANTAR-target RNAs and associated regulation places RNAs as crucial players in controlling metabolic flexibility of mycobacteria, proposing a prominent role for ANTAR regulation across actinobacteria.

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Ramesh, A., Mehta, D., K, A., A, A., Gupta, R.. 2019-06-05. Non-coding RNAs control metabolic state in mycobacteria. https://doi.org/10.1101/660928

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