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bioRxiv · 10.1101/697847

Proteins required for vacuolar function are targets of lysine polyphosphorylation in yeast

McCarthy, L.·Bentley-DeSousa, A.·Denoncourt, A.·Tseng, Y.-C.·Gabriel, M.·Downey, M.
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Abstract

Polyphosphates (polyP) are long chains of inorganic phosphates that can be attached to lysine residues of target proteins as a non-enzymatic post-translational modification. This modification, termed polyphosphorylation, may be particularly prevalent in bacterial and fungal species that synthesize and store large quantities of polyP. In this study, we applied a proven screening strategy to evaluate the polyphosphorylation status of over 200 candidate targets in the budding yeast S. cerevisiae. We report 8 new polyphosphorylated proteins that interact genetically and physically with a previously identified network of targets implicated in ribosome biogenesis. The expanded target network includes vacuolar proteins Prb1 and Apl5, whose modification with polyP suggests a model for feedback regulation of polyP synthesis, while raising additional questions regarding the location of polyphosphorylation in vivo.

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McCarthy, L., Bentley-DeSousa, A., Denoncourt, A., Tseng, Y.-C., Gabriel, M., Downey, M.. 2019-07-10. Proteins required for vacuolar function are targets of lysine polyphosphorylation in yeast. https://doi.org/10.1101/697847

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