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bioRxiv · 10.64898/2026.05.14.725281

GABA antagonises ABA perception and signalling in plants

Long, Y.·Feng, C.·Luo, Y.·Zhou, H.·Lin, P.·Liu, B.·Guo, L.·Jia, A.·Zhang, X.·Zhou, Y.·Song, C.-P.
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Abstract

Abscisic acid (ABA) is a central regulator of plant growth and stress responses. However, it also negatively impact germination, growth, and reproductive performance, highlighting the need for mechanisms that fine-tune its signalling. Here, we identify {gamma}-aminobutyric acid (GABA) as an endogenous antagonist of plant ABA receptor. We show that GABA binds the clade A protein phosphatase-ABI1, disrupting its association with the ABA receptor PYL1, blocking ABA binding, thereby attenuating ABA signalling. GABA modulates ABA-control of stomatal aperture and seed germination, demonstrating its broad physiological influence. Notably, GABA accumulation during stress coincides with the subsequent decline in ABA, consistent with a delayed feedback signal of ABA activity. Together, this work identifies GABA as an antagonist of ABA and provides a mechanism balancing plant stress resilience and growth.

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Long, Y., Feng, C., Luo, Y., Zhou, H., Lin, P., Liu, B., Guo, L., Jia, A., Zhang, X., Zhou, Y., Song, C.-P.. 2026-05-18. GABA antagonises ABA perception and signalling in plants. https://doi.org/10.64898/2026.05.14.725281

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