Payne C T, Zhang F, Lloyd A M
Molecular Cell and Developmental Biology and the Institute for Cellular and Molecular Biology, University of Texas, Austin, Texas 78712-1095, USA.
Genetics. 2000 Nov;156(3):1349-62. doi: 10.1093/genetics/156.3.1349.
Arabidopsis trichome development and differentiation is a well-studied model for plant cell-fate determination and morphogenesis. Mutations in TRANSPARENT TESTA GLABRA1 (TTG1) result in several pleiotropic defects including an almost complete lack of trichomes. The complex phenotype caused by ttg1 mutations is suppressed by ectopic expression of the maize anthocyanin regulator R. Here it is demonstrated that the Arabidopsis trichome development locus GLABRA3 (GL3) encodes an R homolog. GL3 and GLABRA1 (GL1) interact when overexpressed together in plants. Yeast two-hybrid assays indicate that GL3 participates in physical interactions with GL1, TTG1, and itself, but that GL1 and TTG1 do not interact. These data suggest a reiterated combinatorial model for the differential regulation of such diverse developmental pathways as trichome cell-fate determination, root hair spacing, and anthocyanin secondary metabolism.
拟南芥表皮毛的发育与分化是研究植物细胞命运决定和形态发生的一个经典模型。透明种皮光滑1（TTG1）基因的突变会导致多种多效性缺陷，包括几乎完全缺乏表皮毛。玉米花青素调节因子R的异位表达可抑制ttg1突变引起的复杂表型。本文证明拟南芥表皮毛发育基因座GLABRA3（GL3）编码一个R的同源物。当GL3和GLABRA1（GL1）在植物中共同过表达时会相互作用。酵母双杂交实验表明，GL3参与与GL1、TTG1以及自身的物理相互作用，但GL1和TTG1不相互作用。这些数据提示了一个重复组合模型，用于差异调控诸如表皮毛细胞命运决定、根毛间距以及花青素次生代谢等多种不同的发育途径。
