SNF1-related protein kinase 2 directly regulate group C Raf-like protein kinases in abscisic acid signaling

Kamiyama, Y.; Hirotani, M.; Ishikawa, S.; Minegishi, F.; Katagiri, S.; Takahashi, F.; Nomoto, M.; Ishikawa, K.; Kodama, Y.; Tada, Y.; Takezawa, D.; Peck, S. C.; Shinozaki, K.; Umezawa, T.

doi:10.1101/2020.02.04.933978

bioRxiv · 10.1101/2020.02.04.933978

SNF1-related protein kinase 2 directly regulate group C Raf-like protein kinases in abscisic acid signaling

Kamiyama, Y.·Hirotani, M.·Ishikawa, S.·Minegishi, F.·Katagiri, S.·Takahashi, F.·Nomoto, M.·Ishikawa, K.·Kodama, Y.·Tada, Y.·Takezawa, D.·Peck, S. C.·Shinozaki, K.·Umezawa, T.

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Abstract

ABSTRUCTA phytohormone abscisic acid (ABA) has a major role in abiotic stress responses in plants, and subclass III SNF1-related protein kinase 2 (SnRK2) mediates ABA signaling. In this study, we identified Raf36, a group C Raf-like protein kinase in Arabidopsis, as an interacting protein with SnRK2. A series of reverse genetic and biochemical analyses revealed that Raf36 negatively regulates ABA responses and is directly phosphorylated by SnRK2s. In addition, we found that Raf22, another C-type Raf-like kinase, functions partially redundantly with Raf36 to regulate ABA responses. Comparative phosphoproteomic analysis using Arabidopsis wild-type and raf22raf36-1 plants identified proteins that are phosphorylated downstream of Raf36 and Raf22 in planta. Together, these results reveal a novel subsection of ABA-responsive phosphosignaling pathways branching from SnRK2.

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Kamiyama, Y., Hirotani, M., Ishikawa, S., Minegishi, F., Katagiri, S., Takahashi, F., Nomoto, M., Ishikawa, K., Kodama, Y., Tada, Y., Takezawa, D., Peck, S. C., Shinozaki, K., Umezawa, T.. 2020-02-04. SNF1-related protein kinase 2 directly regulate group C Raf-like protein kinases in abscisic acid signaling. https://doi.org/10.1101/2020.02.04.933978

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