Zhan Xiangqiang, Qian Bilian, Cao Fengqiu, Wu Wenwu, Yang Lan, Guan Qingmei, Gu Xianbin, Wang Pengcheng, Okusolubo Temiloluwa A, Dunn Stephanie L, Zhu Jian-Kang, Zhu Jianhua
Shanghai Center for Plant Stress Biology, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai 200032, China.
Department of Plant Science and Landscape Architecture, University of Maryland, 2121 Plant Sciences Building, College Park, Maryland 20742, USA.
Nat Commun. 2015 Sep 25;6:8139. doi: 10.1038/ncomms9139.
The phytohormone abscisic acid (ABA) is important for growth, development and stress responses in plants. Recent research has identified ABA receptors and signalling components that regulate seed germination and stomatal closure. However, proteins that regulate ABA signalling remain poorly understood. Here we use a forward-genetic screen to identify rbm25-1 and rbm25-2, two Arabidopsis mutants with increased sensitivity to growth inhibition by ABA. Using RNA-seq, we found that RBM25 controls the splicing of many pre-mRNAs. The protein phosphatase 2C HAB1, a critical component in ABA signalling, shows a dramatic defect in pre-mRNA splicing in rbm25 mutants. Ectopic expression of a HAB1 complementary DNA derived from wild-type mRNAs partially suppresses the rbm25-2 mutant phenotype. We suggest that RNA splicing is of particular importance for plant response to ABA and that the splicing factor RBM25 has a critical role in this response.
植物激素脱落酸（ABA）对植物的生长、发育和应激反应至关重要。最近的研究已经鉴定出调控种子萌发和气孔关闭的ABA受体及信号传导组分。然而，对调控ABA信号传导的蛋白质仍知之甚少。在此，我们通过正向遗传学筛选鉴定出rbm25-1和rbm25-2，这两个拟南芥突变体对ABA介导的生长抑制更为敏感。通过RNA测序，我们发现RBM25控制许多前体mRNA的剪接。蛋白磷酸酶2C HAB1是ABA信号传导中的关键组分，在rbm25突变体的前体mRNA剪接中表现出显著缺陷。源自野生型mRNA的HAB1互补DNA的异位表达部分抑制了rbm25-2突变体的表型。我们认为RNA剪接对植物对ABA的反应尤为重要，并且剪接因子RBM25在这一反应中起关键作用。
