Crossing paths: Investigating the role of auxin and cytokinin in 3D growth specification

交叉路径：研究生长素和细胞分裂素在 3D 生长规范中的作用

• 批准号: 2748819
• 金额: --
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2748819
• 关键词: Crossing; paths; Investigating; role; auxin

One of the most important events in history was the colonization of land by plants approximately 470 million years ago. This transition coincided with, and was likely facilitated by, the evolution of 3-dimensional (3D) growth. 3D growth is an invariable and pivotal feature of all land plants, and the diverse morphologies exhibited across the globe are a result of the differential regulation of 3D growth processes. Yet, we know very little about how 3D growth is regulated at the genetic level.Studies of 3D growth are difficult using flowering plants as 3D growth begins within the first few divisions of the zygote. Disrupting 3D growth in these plants would therefore cause embryo lethality and provide a narrow timeframe for experimental investigation. Conversely, in the moss Physcomitrium patens, 3D growth (gametophore development) is preceded by a protracted 2-dimensional (2D) filamentous phase that can be cultured indefinitely. P. patens does not need to initiate 3D growth to survive, and thus is an ideal model system to genetically dissect 3D growth. The 2D to 3D growth transition in P. patens is dependent on auxin and cytokinin signaling, is accompanied by highly coordinated changes in cell division plane orientation and culminates in the formation of gametophores with radially organised leaf-like phyllids. Auxin has been consistently implicated in cell division plane orientation within a broad range of developmental contexts and has been implicated as the 'instructive signal' for division plane orientation in developing gametophores.We have isolated a number of 'no gametophores' (nog) mutants that fail to specify 3D growth because they exhibit defects in cell division orientation. This proposal will exploit these 'nog' mutants to unravel the complex auxin-cytokinin crosstalk underpinning the 2D to 3D growth transition in P. patens and will provide unprecedented insight into the regulation of 3D growth in plants.Project Objectives:-Identify the mutations in no gametophore' (nog) mutants that fail to specify 3D growth- Characterize the auxin and cytokinin responses in nog mutants and obtain transcriptomes-Recapitulate 3D growth defects through cell-specific disruption of auxin/cytokinin signaling

历史上最重要的事件之一是大约 4.7 亿年前植物在陆地上的殖民。这种转变与 3 维 (3D) 生长的演变同时发生，并且可能受到 3 维 (3D) 生长的演变的促进。 3D 生长是所有陆地植物的不变且关键的特征，全球范围内呈现出的多样化形态是 3D 生长过程差异调节的结果。然而，我们对如何在基因水平上调控 3D 生长知之甚少。使用开花植物进行 3D 生长研究很困难，因为 3D 生长是在受精卵的最初几个分裂中开始的。因此，破坏这些植物的 3D 生长将导致胚胎致死，并为实验研究提供狭窄的时间范围。相反，在 Physcomitrium patens 苔藓中，3D 生长（配子体发育）之前是一个可以无限培养的延长的 2 维 (2D) 丝状阶段。 P. patens 不需要启动 3D 生长即可生存，因此是从基因角度剖析 3D 生长的理想模型系统。 P. patens 的 2D 到 3D 生长转变依赖于生长素和细胞分裂素信号传导，伴随着细胞分裂平面方向的高度协调变化，并最终形成具有放射状组织的叶状叶状体的配子体。生长素一直与广泛的发育环境中的细胞分裂平面方向有关，并且被认为是配子体发育过程中分裂平面方向的“指导信号”。我们已经分离出许多“无配子体”（nog）突变体无法指定 3D 生长，因为它们在细胞分裂方向上表现出缺陷。该提案将利用这些“nog”突变体来解开支撑 P. patens 2D 到 3D 生长转变的复杂的生长素-细胞分裂素串扰，并将为植物 3D 生长的调控提供前所未有的见解。 项目目标：-识别 P. patens 中的突变无配子体' (nog) 突变体无法指定 3D 生长 - 表征 nog 突变体中的生长素和细胞分裂素反应并获得转录组 - 通过细胞特异性破坏生长素/细胞分裂素信号传导来重现 3D 生长缺陷