BR-bodies provide selectively permeable condensates that stimulate mRNA decay and prevent release of decay intermediates

Al-Husini, N.; Tomares, D. T.; Pfaffenberger, Z.; Muthunayake, N. S.; Samad, M. A.; Zuo, T.; Bitar, O.; Aretakis, J. R.; Bharmal, M. H. M.; Gega, A.; Biteen, J. S.; Childers, W. S.; Schrader, J. M.

doi:10.1101/690628

bioRxiv · 10.1101/690628

BR-bodies provide selectively permeable condensates that stimulate mRNA decay and prevent release of decay intermediates

Al-Husini, N.·Tomares, D. T.·Pfaffenberger, Z.·Muthunayake, N. S.·Samad, M. A.·Zuo, T.·Bitar, O.·Aretakis, J. R.·Bharmal, M. H. M.·Gega, A.·Biteen, J. S.·Childers, W. S.·Schrader, J. M.

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Abstract

Biomolecular condensates play a key role in organizing RNAs and proteins into membraneless organelles. Bacterial RNP-bodies (BR-bodies) are a biomolecular condensate containing the RNA degradosome mRNA decay machinery, but the biochemical function of such organization remains poorly defined. Here we define the RNA substrates of BR-bodies through enrichment of the bodies followed by RNA-seq. We find that long, poorly translated mRNAs, small RNAs, and antisense RNAs are the main substrates, while rRNA, tRNA, and other conserved ncRNAs are excluded from these bodies. BR-bodies stimulate the mRNA decay rate of enriched mRNAs, helping to reshape the cellular mRNA pool. We also observe that BR-body formation promotes complete mRNA decay, avoiding the build-up of toxic endo-cleaved mRNA decay intermediates. The combined selective permeability of BR-bodies for both, enzymes and substrates together with the stimulation of the sub-steps of mRNA decay provide an effective organization strategy for bacterial mRNA decay.

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Al-Husini, N., Tomares, D. T., Pfaffenberger, Z., Muthunayake, N. S., Samad, M. A., Zuo, T., Bitar, O., Aretakis, J. R., Bharmal, M. H. M., Gega, A., Biteen, J. S., Childers, W. S., Schrader, J. M.. 2019-07-05. BR-bodies provide selectively permeable condensates that stimulate mRNA decay and prevent release of decay intermediates. https://doi.org/10.1101/690628

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