Wu Renhong, Citovsky Vitaly
Department of Biochemistry and Cell Biology, State University of New York, Stony Brook, NY 11794-5215, United States.
Biochem Biophys Res Commun. 2017 Jul 1;488(3):547-553. doi: 10.1016/j.bbrc.2017.05.084. Epub 2017 May 17.
Plants use specialized root outgrowths, termed root hairs, to enhance acquisition of nutrients and water, help secure anchorage, and facilitate interactions with soil microbiome. One of the major regulators of this process is GLABRA2 (GL2), a transcriptional repressor of root hair differentiation. However, regulation of the GL2-function is relatively well characterized, it remains completely unknown whether GL2 itself functions in complex with other transcriptional regulators. We identified GIR1 and GIR2, a plant-specific two-member family of closely related proteins that interact with GL2. Loss-of-function mutants of GIR1 and GIR2 enhanced development of root hair whereas gain-of-function mutants repressed it. Thus, GIR1 and GIR2 might function as adaptor proteins that associate with GL2 and participate in control of root hair formation.
植物利用称为根毛的特化根生长物来增强养分和水分的获取，帮助稳固锚定，并促进与土壤微生物群的相互作用。该过程的主要调节因子之一是GLABRA2（GL2），它是根毛分化的转录抑制因子。然而，尽管对GL2功能的调节已有相对充分的了解，但GL2本身是否与其他转录调节因子形成复合物发挥作用仍完全未知。我们鉴定出了GIR1和GIR2，它们是植物特有的、由两个密切相关的蛋白质组成的家族，能与GL2相互作用。GIR1和GIR2的功能缺失突变体增强了根毛的发育，而功能获得突变体则抑制了根毛发育。因此，GIR1和GIR2可能作为衔接蛋白与GL2结合，并参与根毛形成的调控。
