State Key Laboratory of Crop Stress Biology for Arid Areas, College of Agronomy, Northwest A&F University, Yangling, Shaanxi, China.
State Key Laboratory for Agrobiotechnology, Key Laboratory of Crop Heterosis Utilization (MOE), Beijing Key Laboratory of Crop Genetic Improvement, China Agricultural University, Beijing, China.
Plant Biotechnol J. 2018 Mar;16(3):714-726. doi: 10.1111/pbi.12822. Epub 2017 Sep 20.
Plant can acquire tolerance to environmental stresses via transcriptome reprogramming at transcriptional and alternative splicing (AS) levels. However, how AS coordinates with transcriptional regulation to contribute to abiotic stresses responses is still ambiguous. In this study, we performed genome-wide analyses of AS responses to drought stress (DS), heat stress (HS) and their combination (HD) in wheat seedlings, and further compared them with transcriptional responses. In total, we found 200, 3576 and 4056 genes exhibiting significant AS pattern changes in response to DS, HS and HD, respectively, and combined drought and heat stress can induce specific AS compared with individual one. In addition, wheat homeologous genes exhibited differential AS responses under stress conditions that more AS events occurred on B subgenome than on A and D genomes. Comparison of genes regulated at AS and transcriptional levels showed that only 12% of DS-induced AS genes were subjected to transcriptional regulation, whereas the proportion increased to ~40% under HS and HD. Functional enrichment analysis revealed that abiotic stress-responsive pathways tended to be highly overrepresented among these overlapped genes under HS and HD. Thus, we proposed that transcriptional regulation may play a major role in response to DS, which coordinates with AS regulation to contribute to HS and HD tolerance in wheat.
植物可以通过转录组重编程在转录和选择性剪接（AS）水平上获得对环境胁迫的耐受性。然而，AS 如何与转录调控协调以响应非生物胁迫仍然不清楚。在这项研究中，我们对小麦幼苗对干旱胁迫（DS）、热胁迫（HS）及其组合（HD）的 AS 反应进行了全基因组分析，并进一步将其与转录反应进行了比较。总的来说，我们发现分别有 200、3576 和 4056 个基因对 DS、HS 和 HD 表现出显著的 AS 模式变化，并且与单一胁迫相比，干旱和热胁迫的组合可以诱导特定的 AS。此外，小麦同源基因在胁迫条件下表现出不同的 AS 反应，即在 B 亚基因组上发生的 AS 事件比在 A 和 D 基因组上更多。在 AS 和转录水平上受调控的基因的比较表明，只有 12%的 DS 诱导的 AS 基因受到转录调控，而在 HS 和 HD 下，这一比例增加到约 40%。功能富集分析表明，在 HS 和 HD 下，这些重叠基因中与非生物胁迫反应途径高度富集。因此，我们提出转录调控可能在 DS 反应中起主要作用，它与 AS 调控协调，有助于小麦对 HS 和 HD 的耐受。
