Coordination of proximal-distal and adaxial-abaxial patterning during early ovule development of Arabidopsis thaliana

拟南芥胚珠早期发育过程中近端-远端和近轴-远轴模式的协调

• 批准号: 19166016
• 负责人: Professor Dr. Kay Schneitz
• 金额: --
• 依托单位: Professur für Entwicklungsbiologie der Pflanzen
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2005
• 资助国家: 德国
• 起止时间: 2004-12-31 至 2012-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/19166016?language=en
• 关键词: Coordination; proximal; distal; adaxial; abaxial

Sexual reproduction is a salient aspect of plants. Within the flower of angiosperms the gynoecium carries one or multiple ovules, the major female reproductive organs. The ovule harbors the egg cell, it is the site where fertilization occurs and the embryo develops during seed formation. Apart from their exciting biology, the ovules of the model plant Arabidopsis thaliana have gained attraction as a prominent model system to study organogenesis. A major question relates to the molecular basis of pattern formation in the early ovule primordium. In previous research we identified a number of genes with a role in early ovule development. Our genetic evidence suggests that NOZZLE (NZZ), encoding a putative transcription factor, coordinates proximaldistal and adaxia-abaxial (anterior-posterior) pattern formation in the early ovule by negatively regulating the INNER NO OUTER (INO) autoregulatory feedback loop. INO is a member of the YABBY family, which is implied in the regulation of abaxial identity in lateral organs, and affects outer integument development. The idea is that precocious activation of INO eventually results in aberrant P-D pattern formation. Thus, differentiation along the adaxial-abaxial axis in the chalaza may not begin before development along the P-D axis has proceeded to a certain extent. We also obtained in vitro data indicating that the NZZ and at least some YABBY proteins, including INO, interact directly. The first goal of this proposal is to test if the NZZ-INO interaction occurs in vivo using biochemical, in vivo imaging and molecular-genetic approaches. The second line of experiments aims at a better understanding of the molecular basis of this interaction and assesses the generality of the NZZ-YABBY protein interactions. The third goal consists in the molecular characterisation of a new genetic factor involved in early outer integument development.

有性生殖是植物的一个显著方面。在被子植物的花中，雌蕊携带一个或多个胚珠，这是雌性的主要生殖器官。胚珠孕育着卵细胞，是受精发生的地方，也是种子形成过程中胚胎发育的地方。模式植物拟南芥（Arabidopsis thaliana）的胚珠除了具有令人兴奋的生物学特性外，还作为研究器官发生的重要模式系统而受到关注。一个主要的问题涉及到早期胚珠原基模式形成的分子基础。在之前的研究中，我们发现了一些在早期胚珠发育中起作用的基因。我们的遗传证据表明，喷嘴（NZZ）编码一种推定的转录因子，通过负调控INNER NO OUTER （INO）自调节反馈回路，协调胚珠早期近端-远端和轴-背（前后）模式的形成。INO是YABBY家族的一员，该家族参与调节外侧器官的背面身份，并影响外被的发育。这个想法是过早激活INO最终导致异常的P-D模式形成。因此，在沿P-D轴发育到一定程度之前，合带内沿正-背轴的分化可能不会开始。我们还获得了体外数据，表明NZZ和至少一些YABBY蛋白，包括INO，直接相互作用。本提案的第一个目标是使用生化，体内成像和分子遗传学方法测试NZZ-INO相互作用是否在体内发生。第二组实验旨在更好地理解这种相互作用的分子基础，并评估NZZ-YABBY蛋白相互作用的普遍性。第三个目标包括参与早期外被发育的新遗传因素的分子特征。