背景:升高的环境温度会显著影响植物生长,发展,和繁殖。揭示植物的温度调节机制非常重要,为了增加我们对植物热形态发生的基本理解,因为它在应用科学方面的潜力,并帮助植物育种者提高植物的热恢复能力。热形态发生,对温暖温度的发育反应,主要在幼苗和开花时间的调节中进行了研究。植物色素B和植物色素相互作用因子(PIF),特别是PIF4,是这一反应的关键组成部分。然而,其他成人营养组织和生殖结构的热响应尚未得到系统评估,特别是关于phyB和PIF的参与。
结果:我们在组合和整合表型平台中筛选了野生型和几种phyB-PIF4途径拟南芥突变体系的温度响应,用于土壤中的根系生长,射击,花序,和种子。我们的发现表明,phyB-PIF4通常参与整个植物发育过程中温度信号的传递,包括生殖阶段。此外,我们确定了芽和根组织之间对高环境温度的相关响应。通过监测生殖器官中转录水平的变化来补充这种整合和自动化的表型。在高环境温度下生长的植物的雌蕊的转录组学分析确定了关键要素,这些要素可以深入了解温度诱导的受精率降低背后的分子机制。这些包括生长素代谢的下调,涉及生长素信号传导的基因上调,miRNA156和miRNA160途径,和花粉管引诱剂。
结论:我们的发现表明,phyB-PIF4参与温度信号的解释在整个植物发育过程中普遍存在,包括与繁殖直接相关的过程。
BACKGROUND: The increasing ambient temperature significantly impacts plant growth, development, and reproduction. Uncovering the temperature-regulating mechanisms in plants is of high importance, for increasing our fundamental understanding of plant thermomorphogenesis, for its potential in applied science, and for aiding plant breeders in improving plant thermoresilience. Thermomorphogenesis, the developmental response to warm temperatures, has been primarily studied in seedlings and in the regulation of flowering time. PHYTOCHROME B and PHYTOCHROME-INTERACTING FACTORs (PIFs), particularly PIF4, are key components of this response. However, the thermoresponse of other adult vegetative tissues and reproductive structures has not been systematically evaluated, especially concerning the involvement of phyB and PIFs.
RESULTS: We screened the temperature responses of the wild type and several phyB-PIF4 pathway Arabidopsis mutant lines in combined and integrative phenotyping platforms for root growth in soil, shoot, inflorescence, and seed. Our findings demonstrate that phyB-PIF4 is generally involved in the relay of temperature signals throughout plant development, including the reproductive stage. Furthermore, we identified correlative responses to high ambient temperature between shoot and root tissues. This integrative and automated phenotyping was complemented by monitoring the changes in transcript levels in reproductive organs. Transcriptomic profiling of the pistils from plants grown under high ambient temperature identified key elements that may provide insight into the molecular mechanisms behind temperature-induced reduced fertilization rate. These include a downregulation of auxin metabolism, upregulation of genes involved auxin signalling, miRNA156 and miRNA160 pathways, and pollen tube attractants.
CONCLUSIONS: Our findings demonstrate that phyB-PIF4 involvement in the interpretation of temperature signals is pervasive throughout plant development, including processes directly linked to reproduction.