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bioRxiv · 10.1101/504373

Pyrophosphate modulates stress responses via SUMOylation

Patir-Nebioglu, G.·Andres, Z.·Krebs, M.·Fink, F.·Drzewicka, K.·Stankovic-Valentin, N.·Segami, S.·Schuck, S.·Büttner, M.·Hell, R.·Maeshima, M.·Melchior, F.·Schumacher, K.
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Abstract

Pyrophosphate (PPi), a byproduct of macromolecule biosynthesis is maintained at low levels by soluble inorganic pyrophosphatases (sPPase) found in all eukaryotes. In plants, H+-pumping pyrophosphatases (H+-PPase) convert the substantial energy present in PPi into an electrochemical gradient. We show here, that both cold- and heat stress sensitivity of fugu5 mutants lacking the major H+-PPase isoform AVP1 is caused by reduced SUMOylation. In addition, we show that increased PPi concentrations interfere with SUMOylation in yeast and we provide evidence that SUMO activating E1-enzymes are inhibited by micromolar concentrations of PPi in a non-competitive manner. Taken together, our results do not only provide a mechanistic explanation for the beneficial effects of AVP1 overexpression in plants but they also highlight PPi as an important integrator of metabolism and stress tolerance.

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Patir-Nebioglu, G., Andres, Z., Krebs, M., Fink, F., Drzewicka, K., Stankovic-Valentin, N., Segami, S., Schuck, S., Büttner, M., Hell, R., Maeshima, M., Melchior, F., Schumacher, K.. 2018-12-22. Pyrophosphate modulates stress responses via SUMOylation. https://doi.org/10.1101/504373

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