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4.7亿年前的植物殖民地殖民地。这种转变恰逢3维（3D）生长的演变，并且很可能促进了这种过渡。 3D生长是所有土地植物的一个不变且关键的特征，在全球范围内表现出的多种形态是3D生长过程的差异调节的结果。然而，我们对在遗传水平上如何调节3D生长几乎不了解。使用开花植物的3D生长的研究很难随着3D生长在合子的前几个部门的开始。因此，破坏这些植物的3D生长将导致胚胎致死性，并为实验研究提供狭窄的时间范围。相反，在苔藓的Physcomitrium patens中，3D生长（配子体发育）是持久的二维（2D）丝状相，可以无限期地培养。 P. Patens不需要启动3D生长即可生存，因此是遗传剖析3D生长的理想模型系统。 P. p.patens中的2D至3D生长转变取决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的变化，并在形成具有径向有组织的叶状叶绿体的配子载体中。在广泛的发育环境中，生长素一直与细胞分裂平面取向有关，并被视为开发配子载体中的除法平面取向的“启发性信号”。我们已经隔离了许多“没有配子载体”突变体，这些突变体未能指定3D生长，因为它们在细胞分裂分裂方面表现出缺陷。该提议将利用这些“ NOG”突变体来阐明复杂的生长素 - 循环蛋白串扰，这些串扰是P. Patens中2d至3D增长过渡的基础，并将提供对植物中3D生长的前所未有的洞察力。 NOG突变体中的响应并通过生长素/细胞分裂素信号的细胞特异性破坏获得转录组重新定位3D生长缺陷