Kupriyanova Evgenia V, Albert Evgeniy V, Bliznina Aleksandra I, Mamoshina Polina O, Ezhova Tatiana A
Department of Genetics, Faculty of Biology, Lomonosov Moscow State University, 119234, Leninskiye Gory 1/12, Moscow 119234, Russia
Department of Genetics, Faculty of Biology, Lomonosov Moscow State University, 119234, Leninskiye Gory 1/12, Moscow 119234, Russia.
Biol Open. 2017 Jun 15;6(6):832-843. doi: 10.1242/bio.024422.
DNA topoisomerase I alpha (TOP1α) plays a specific role in development and is required for stem cell regulation in shoot and floral meristems. Recently, a new role independent of meristem functioning has been described for TOP1α, namely flowering time regulation. The same feature had been detected by us earlier for , a mutant allele of In this study we clarify the effects of on bolting initiation and analyze the molecular basis of its role on flowering time regulation. We show that mutation leads to a constitutive shade avoidance syndrome, accompanied by leaf hyponasty, petiole elongation, lighter leaf color and early bolting. Other alleles of demonstrate the same shade avoidance response. RNA sequencing confirmed the activation of shade avoidance gene pathways in mutant plants It also revealed the repression of many genes controlling floral meristem identity and organ morphogenesis. Our research further expands the knowledge of TOP1α function in plant development and reveals that besides stem cell maintenance TOP1α plays an important new role in regulating the adaptive plant response to light stimulus and flower development.
DNA拓扑异构酶Iα（TOP1α）在植物发育中发挥特定作用，是茎尖和花分生组织中干细胞调控所必需的。最近，人们发现TOP1α具有一种独立于分生组织功能的新作用，即调控开花时间。我们之前在phyA-201（phyA的一个突变等位基因）中也检测到了同样的特征。在本研究中，我们阐明了phyA-201对抽薹起始的影响，并分析了其在开花时间调控中作用的分子基础。我们发现phyA-201突变会导致组成型避荫综合征，表现为叶片下弯、叶柄伸长、叶片颜色变浅和提前抽薹。phyA的其他等位基因也表现出相同的避荫反应。RNA测序证实了phyA-201突变体植物中避荫基因途径的激活。它还揭示了许多控制花分生组织特性和器官形态发生的基因受到抑制。我们的研究进一步拓展了对TOP1α在植物发育中功能的认识，并揭示了除维持干细胞功能外，TOP1α在调节植物对光刺激的适应性反应和花发育方面发挥着重要的新作用。
