The Phosphate Deprivation Response is Mediated by an Interaction between Brassinosteroid Signaling and Zinc in Tomato

Demirer, G. S.; Gibson, D. J.; Yue, X.; Pan, K.; Elishav, E.; Khandal, H.; Horev, G.; Tarkowska, D.; Canto-Pastor, A.; Kong, S.; Maloof, J.; Savaldi-Goldstein, S.; Brady, S.

doi:10.1101/2022.09.21.508943

bioRxiv · 10.1101/2022.09.21.508943

The Phosphate Deprivation Response is Mediated by an Interaction between Brassinosteroid Signaling and Zinc in Tomato

Demirer, G. S.·Gibson, D. J.·Yue, X.·Pan, K.·Elishav, E.·Khandal, H.·Horev, G.·Tarkowska, D.·Canto-Pastor, A.·Kong, S.·Maloof, J.·Savaldi-Goldstein, S.·Brady, S.

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Abstract

Phosphate is a necessary macronutrient for basic biological processes, plant growth, and agriculture. Plants modulate their root system architecture and cellular processes to adapt to phosphate deprivation albeit with a growth penalty. Excess application of phosphate fertilizer, on the other hand, leads to eutrophication and has a negative environmental impact. Moreover, phosphate mined from rock reserves is a finite and non-recyclable resource and its levels are nearing complete depletion. Here, we show that Solanum pennellii, a wild relative of tomato, is partially insensitive to phosphate deprivation. Furthermore, it mounts a constitutive response under phosphate sufficiency. We demonstrate that activated brassinosteroid signaling through a tomato BZR1 ortholog gives rise to the same constitutive phosphate deficiency response, which is dependent on zinc over-accumulation. Collectively, these results reveal an additional strategy by which plants can adapt to phosphate starvation.

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Demirer, G. S., Gibson, D. J., Yue, X., Pan, K., Elishav, E., Khandal, H., Horev, G., Tarkowska, D., Canto-Pastor, A., Kong, S., Maloof, J., Savaldi-Goldstein, S., Brady, S.. 2022-09-22. The Phosphate Deprivation Response is Mediated by an Interaction between Brassinosteroid Signaling and Zinc in Tomato. https://doi.org/10.1101/2022.09.21.508943

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