The dimorphic diaspore model Aethionema arabicum (Brassicaceae): Distinct molecular and morphological control of responses to parental and germination temperatures
The dimorphic diaspore model Aethionema arabicum (Brassicaceae): Distinct molecular and morphological control of responses to parental and germination temperatures
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二相水硬铝石模型 Aethionema arabicum（十字花科）：对亲本温度和发芽温度反应的独特分子和形态控制
DOI：
10.1101/2023.12.14.571707
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Chandler J
中科院分区：
文献类型：
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作者：
Chandler J
在不可预测的环境条件下，植物通常具有多样化的下注对冲策略，以确保在更大范围的可变环境因素下的适应性。一个显著的例子是一水硬体（种子和果实）的异型性，这种异型性是为了最大化arabicum（芸苔科）的物种生存而进化出来的，在这种异型性中，外部和内源的触发因素允许在同一植物上产生两种不同的一水硬体。利用这一二态一水硬膜模型，我们确定了不同温度下粘液种子（M+种子形态）、分散不裂果实（IND果实形态）和IND果实去皮（果皮）获得的裸露无粘液M -种子的分子、生物物理和生态生理机制。M+种子、IND果实和M -种子的大规模比较转录组和激素分析为它们不同的热响应提供了全面的数据集。种子中共表达基因模块的形态特异性差异，以及种子和果皮激素含量的差异，确定了IND果皮通过产生影响脱落酸（ABA）敏感性的缺氧来强制果皮休眠的作用。这涉及形态特异性转录因子的表达、缺氧反应和细胞壁重塑基因，以及ABA代谢、运输和信号传导的改变。亲本温度影响ABA含量和ABA相关基因表达，改变IND果皮的生物力学特性。阐明一水硬铝石异型性的分子框架可以为了解全球温度变化的发育反应提供帮助。
Plants in habitats with unpredictable conditions often have diversified bet-hedging strategies that ensure fitness over a wider range of variable environmental factors. A striking example is the diaspore (seed and fruit) heteromorphism that evolved to maximize species survival inAethionema arabicum(Brassicaceae) in which external and endogenous triggers allow the production of two distinct diaspores on the same plant. Using this dimorphic diaspore model, we identified contrasting molecular, biophysical, and ecophysiological mechanisms in the germination responses to different temperatures of the mucilaginous seeds (M+seed morphs), the dispersed indehiscent fruits (IND fruit morphs), and the bare non-mucilaginous M−seeds obtained by pericarp (fruit coat) removal from IND fruits. Large-scale comparative transcriptome and hormone analyses of M+seeds, IND fruits, and M−seeds provided comprehensive datasets for their distinct thermal responses. Morph-specific differences in co-expressed gene modules in seeds, as well as in seed and pericarp hormone contents, identified a role of the IND pericarp in imposing coat dormancy by generating hypoxia affecting abscisic acid (ABA) sensitivity. This involved expression of morph-specific transcription factors, hypoxia response, and cell wall remodeling genes, as well as altered ABA metabolism, transport, and signaling. Parental temperature affected ABA contents and ABA-related gene expression and altered IND pericarp biomechanical properties. Elucidating the molecular framework underlying the diaspore heteromorphism can provide insight into developmental responses to globally changing temperatures.