mRNA structure determines specificity of a polyQ-driven phase separation

Langdon, E. M.; Billingsly, P.; Ghanbari Niaki, A.; McLaughlin, G.; Weidmann, C.; Gerbich, T.; Termini, C. M.; Weeks, K. M.; Myong, S.; Gladfelter, A.

doi:10.1101/233817

bioRxiv · 10.1101/233817

mRNA structure determines specificity of a polyQ-driven phase separation

Langdon, E. M.·Billingsly, P.·Ghanbari Niaki, A.·McLaughlin, G.·Weidmann, C.·Gerbich, T.·Termini, C. M.·Weeks, K. M.·Myong, S.·Gladfelter, A.

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Abstract

RNA promotes liquid-liquid phase separation (LLPS) to build membrane-less compartments in cells. How distinct molecular compositions are established and maintained in these liquid compartments is unknown. Here we report that secondary structure allows mRNAs to self-associate and determines if an mRNA is recruited to or excluded from liquid compartments. The polyQ-protein Whi3 induces conformational changes in RNA structure and generates distinct molecular fluctuations depending on the RNA sequence. These data support a model in which structure-based, RNA-RNA interactions promote assembly of distinct droplets and protein-driven, conformational dynamics of the RNA maintain this identity. Thus, the shape of RNA can promote the formation and coexistence of the diverse array of RNA-rich liquid compartments found in a single cell.\n\nOne Sentence SummaryIdentity in cellular, phase-separated compartments arises from RNA-RNA complexes encoded by mRNA secondary structures.

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Langdon, E. M., Billingsly, P., Ghanbari Niaki, A., McLaughlin, G., Weidmann, C., Gerbich, T., Termini, C. M., Weeks, K. M., Myong, S., Gladfelter, A.. 2017-12-13. mRNA structure determines specificity of a polyQ-driven phase separation. https://doi.org/10.1101/233817

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