论文题目: ABA signalling is fine-tuned by antagonistic HAB1 variants

论文编号:
作者: Zhijuan Wang(王志娟), Hongtao Ji（纪洪涛）, Bingjian Yuan（袁冰剑）, Shuangfeng Wang（王双凤）, Chao Su（苏超）, Bin Yao（姚斌）, Hongtao Zhao（赵红桃）, Xia Li（李霞）
刊物名称: Nature Communications
卷期页码: , ,
发表年度: 2015
DOI: http://doi.org/10.1038/ncomms9138
摘要: 　　Group A protein type 2C phosphatases (PP2Cs) are negative regulators of abscisic acid (ABA) signalling and plant adaptation to stress. However, our knowledge of the regulation of PP2C activity is limited. Here we report that the PP2C HAB1 undergoes alternative splicing to produce two splice variants, which encode HAB1.1 and HAB1.2, that play opposing roles in ABA-mediated seed germination and ABA-mediated post-germination developmental arrest. HAB1.2 is predominately formed in the presence of ABA and prevents seed germination and post-germinative growth. HAB1.2 interacts with OST1, but cannot inhibit OST1 kinase activity; thus, it functions as a positive regulator of ABA signalling. We also identified an RNA-recognition motif-containing protein, RBM25, as a potential regulator of HAB1 alternative splicing and molecular diversity. Our results reveal a mechanism for turning ABA signalling on and off and for plant adaptation to abiotic stress.