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bioRxiv · 10.1101/353979

Trans-splicing of mRNAs links gene transcription to translational control regulated by mTOR

Danks, G.·Galbiati, H.·Raasholm, M.·Torres Cleuren, Y. N.·Valen, E.·Navratilova, P.·Thompson, E. M.
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Abstract

In phylogenetically diverse organisms, the 5 ends of a subset of mRNAs are trans-spliced with a spliced leader (SL) RNA. The functions of SL trans-splicing, however, remain largely enigmatic. Here, we quantified translation genome-wide in the marine chordate, Oikopleura dioica, under inhibition of mTOR, a central growth regulator. Translation of trans-spliced TOP mRNAs was suppressed, showing that the SL sequence permits nutrient-dependent translational control of growth-related mRNAs. Under crowded, nutrient-limiting conditions, O. dioica continues to filter-feed, but arrests growth until favorable conditions return. Upon release from such conditions, initial recovery was independent of nutrient-responsive, trans-spliced genes, suggesting animal density sensing as a first trigger for resumption of development. Our results demonstrate a role for trans-splicing in the coordinated translational down-regulation of nutrient-responsive genes under limiting conditions.

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Danks, G., Galbiati, H., Raasholm, M., Torres Cleuren, Y. N., Valen, E., Navratilova, P., Thompson, E. M.. 2018-06-22. Trans-splicing of mRNAs links gene transcription to translational control regulated by mTOR. https://doi.org/10.1101/353979

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