The protein kinase FvRIPK1 regulates plant morphogenesis by ABA signaling using seed genetic transformation in strawberry.

A strawberry RIPK1, a leu-rich repeat receptor-like protein kinase, is previously demonstrated to be involved in fruit ripening as a positive regulator; however, its role in vegetable growth remains unknown. Here, based on our first establishment of -mediated transformation of germinating seeds in diploid strawberry by /, a reporter gene that functioned in chlorophyll biosynthesis, we got mutants. Downregulation of inhibited plant morphogenesis, showing curled leaves; also, this silencing significantly reduced and transcripts and promoted , , and transcripts. Interestingly, the downregulation of the expression could not affect transcripts but remarkably reduced transcripts and promoted , , and transcripts in the contrast of the non-transgenic plants to the /-RNAi plants, in which chlorophyll contents were not affected but had abscisic acid (ABA) response in stomata movement and drought stress. The distinct expression level of and , together with the similar expression level of and in the - and -RNAi plants, suggested that FvRIPK1 regulated plant morphogenesis probably by ABA signaling. In addition, FvRIPK1 interacted with FvSnRK2.6 and phosphorylated each other, thus forming the FvRIPK1-FvSnRK2.6 complex. In conclusion, our results provide new insights into the molecular mechanism of FvRIPK1 in plant growth.