Chromosome doubling mediates superior drought tolerance in Lycium ruthenicum via abscisic acid signaling
Chromosome doubling mediates superior drought tolerance in Lycium ruthenicum via abscisic acid signaling
复制标题
染色体加倍通过脱落酸信号介导黑果枸杞的优异耐旱性
DOI：
10.1038/s41438-020-0260-1
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发表时间：
2020-04-01
影响因子：
8.7
通讯作者：
Chen, Jinhuan
中科院分区：
文献类型：
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作者：
Rao, Shupei;Tian, Yuru;Chen, Jinhuan
植物不断受到不利的外部刺激的影响，这影响了它们的生产力和生长。基因组成和表达模式的差异导致同源多倍体植物表现出不同的生理现象，其中增强的环境适应性是多倍体化赋予的强大表型。二倍体和同源四倍体植物在分子水平上的抗逆性差异机制尚不清楚。在这项研究中，通过高质量的单个RNA分子的单分子实时（SMRT）测序获得的全长转录谱作为背景，与下一代转录组和蛋白质组技术相结合，以探测同源四倍体的分子机制的变化。在自然条件下，四倍体的阿坝含量比二倍体高78.4%，在严重干旱胁迫下表现出上级的抗逆性。二倍体和同源四倍体在正常生长条件下观察到的转录组谱的实质性差异主要与阿坝生物合成和信号转导途径有关，并且编码关键合成酶的9-顺式环氧类胡萝卜素双加氧酶1（NCED 1）和NCED 2显著上调。ABF 5-like基因表达的增加是促进阿坝信号通路和下游靶基因激活的关键因素。此外，阿坝还在翻译水平上强烈诱导渗透调节蛋白的表达，从而提高植物的抗逆性。我们认为阿坝影响四倍体和二倍体植物抗旱性的内在机制，以了解提高多倍体植物非生物胁迫耐受性的生理和分子机制。
Plants are continuously affected by unfavorable external stimuli, which influences their productivity and growth. Differences in gene composition and expression patterns lead homologous polyploid plants to exhibit different physiological phenomena, among which enhanced environmental adaptability is a powerful phenotype conferred by polyploidization. The mechanisms underlying the differences in stress tolerance between diploids and autotetraploids at the molecular level remain unclear. In this research, a full-length transcription profile obtained via the single-molecule real-time (SMRT) sequencing of high-quality single RNA molecules for use as background was combined with next-generation transcriptome and proteome technologies to probe the variation in the molecular mechanisms of autotetraploids. Tetraploids exhibited an increase in ABA content of 78.4% under natural conditions and a superior stress-resistance phenotype under severe drought stress compared with diploids. The substantial differences in the transcriptome profiles observed between diploids and autotetraploids under normal growth conditions were mainly related to ABA biosynthesis and signal transduction pathways, and 9-cis-epoxycarotenoid dioxygenase 1 (NCED1) and NCED2, which encode key synthetic enzymes, were significantly upregulated. The increased expression of the ABRE-binding factor 5-like (ABF5-like) gene was a pivotal factor in promoting the activation of the ABA signaling pathway and downstream target genes. In addition, ABA strongly induced the expression of osmotic proteins to increase the stress tolerance of the plants at the translational level. We consider the intrinsic mechanisms by which ABA affects drought resistance in tetraploids and diploids to understand the physiological and molecular mechanisms that enhance abiotic stress tolerance in polyploid plants.