Khan Madiha, Ragni Laura, Tabb Paul, Salasini Brenda C, Chatfield Steven, Datla Raju, Lock John, Kuai Xiahezi, Després Charles, Proveniers Marcel, Yongguo Cao, Xiang Daoquan, Morin Halima, Rullière Jean-Pierre, Citerne Sylvie, Hepworth Shelley R, Pautot Véronique
Department of Biology, Carleton University, Ottawa, Ontario, Canada K1S 5B6 (M.K., P.T., B.C.S., S.Ch., J.L., S.R.H.);Institut Jean-Pierre Bourgin, Unité Mixte de Recherche 1318 Institut National de la Recherche Agronomique-AgroParisTech, Bâtiment 2, Institut National de la Recherche Agronomique Centre de Versailles-Grignon, 78026 Versailles cedex, France (L.R., H.M., J.-P.R., S.Ci., V.P.); Plant Biotechnology Institute,National Research Council Canada, Saskatoon, Saskatchewan, Canada S7N 0W9 (R.D., C.Y., D.X.);Department of Biological Sciences, Brock University, St. Catharines, Ontario, Canada L2S 3A1 (X.K, C.D.); andMolecular Plant Physiology, Department of Biology, Faculty of Sciences, Utrecht University, CH-3584 Utrecht, The Netherlands (M.P.).
Department of Biology, Carleton University, Ottawa, Ontario, Canada K1S 5B6 (M.K., P.T., B.C.S., S.Ch., J.L., S.R.H.);Institut Jean-Pierre Bourgin, Unité Mixte de Recherche 1318 Institut National de la Recherche Agronomique-AgroParisTech, Bâtiment 2, Institut National de la Recherche Agronomique Centre de Versailles-Grignon, 78026 Versailles cedex, France (L.R., H.M., J.-P.R., S.Ci., V.P.); Plant Biotechnology Institute,National Research Council Canada, Saskatoon, Saskatchewan, Canada S7N 0W9 (R.D., C.Y., D.X.);Department of Biological Sciences, Brock University, St. Catharines, Ontario, Canada L2S 3A1 (X.K, C.D.); andMolecular Plant Physiology, Department of Biology, Faculty of Sciences, Utrecht University, CH-3584 Utrecht, The Netherlands (M.P.)
Plant Physiol. 2015 Nov;169(3):2166-86. doi: 10.1104/pp.15.00915. Epub 2015 Sep 28.
In the model plant Arabidopsis (Arabidopsis thaliana), endogenous and environmental signals acting on the shoot apical meristem cause acquisition of inflorescence meristem fate. This results in changed patterns of aerial development seen as the transition from making leaves to the production of flowers separated by elongated internodes. Two related BEL1-like homeobox genes, PENNYWISE (PNY) and POUND-FOOLISH (PNF), fulfill this transition. Loss of function of these genes impairs stem cell maintenance and blocks internode elongation and flowering. We show here that pny pnf apices misexpress lateral organ boundary genes BLADE-ON-PETIOLE1/2 (BOP1/2) and KNOTTED-LIKE FROM ARABIDOPSIS THALIANA6 (KNAT6) together with ARABIDOPSIS THALIANA HOMEOBOX GENE1 (ATH1). Inactivation of genes in this module fully rescues pny pnf defects. We further show that BOP1 directly activates ATH1, whereas activation of KNAT6 is indirect. The pny pnf restoration correlates with renewed accumulation of transcripts conferring floral meristem identity, including FD, SQUAMOSA PROMOTER-BINDING PROTEIN LIKE genes, LEAFY, and APETALA1. To gain insight into how this module blocks flowering, we analyzed the transcriptome of BOP1-overexpressing plants. Our data suggest a central role for the microRNA156-SQUAMOSA PROMOTER BINDING PROTEIN-LIKE-microRNA172 module in integrating stress signals conferred in part by promotion of jasmonic acid biosynthesis. These data reveal a potential mechanism by which repression of lateral organ boundary genes by PNY-PNF is essential for flowering.
在模式植物拟南芥中，作用于茎尖分生组织的内源和环境信号会促使花序分生组织命运的获得。这导致地上部分发育模式发生变化，表现为从长叶到产生由伸长节间隔开的花的转变。两个相关的类BEL1同源异型盒基因，PENNYWISE（PNY）和POUND-FOOLISH（PNF），促成了这一转变。这些基因功能的丧失会损害干细胞的维持，并阻碍节间伸长和开花。我们在此表明，pny pnf顶端会错误表达侧器官边界基因叶柄上的叶片1/2（BOP1/2）、拟南芥类结瘤基因6（KNAT6）以及拟南芥同源异型盒基因1（ATH1）。该模块中基因的失活完全挽救了pny pnf的缺陷。我们进一步表明，BOP1直接激活ATH1，而KNAT6的激活是间接的。pny pnf的恢复与赋予花分生组织身份的转录本的重新积累相关，包括FD、类SQUAMOSA启动子结合蛋白基因家族、LEAFY和APETALA1。为深入了解该模块如何阻止开花，我们分析了过表达BOP1的植物的转录组。我们的数据表明，微小RNA156 - SQUAMOSA启动子结合蛋白 - 微小RNA172模块在整合部分由茉莉酸生物合成促进所赋予的胁迫信号中起核心作用。这些数据揭示了一种潜在机制，通过该机制，PNY - PNF对侧器官边界基因的抑制对于开花至关重要。
