Bioscience and Biotechnology Center, Nagoya University, Nagoya, Aichi 464-8601, Japan
Bioscience and Biotechnology Center, Nagoya University, Nagoya, Aichi 464-8601, Japan.
Plant Physiol. 2018 Apr;176(4):3081-3102. doi: 10.1104/pp.17.00858. Epub 2018 Feb 23.
Water submergence is an environmental factor that limits plant growth and survival. Deepwater rice () adapts to submergence by rapidly elongating its internodes and thereby maintaining its leaves above the water surface. We performed a comparative RNA sequencing transcriptome analysis of the shoot base region, including basal nodes, internodes, and shoot apices of seedlings at two developmental stages from two varieties with contrasting deepwater growth responses. A transcriptomic comparison between deepwater rice cv C9285 and nondeepwater rice cv Taichung 65 revealed both similar and differential expression patterns between the two genotypes during submergence. The expression of genes related to gibberellin biosynthesis, trehalose biosynthesis, anaerobic fermentation, cell wall modification, and transcription factors that include ethylene-responsive factors was significantly different between the varieties. Interestingly, in both varieties, the jasmonic acid content at the shoot base decreased during submergence, while exogenous jasmonic acid inhibited submergence-induced internode elongation in cv C9285, suggesting that jasmonic acid plays a role in the submergence response of rice. Furthermore, a targeted de novo transcript assembly revealed transcripts that were specific to cv C9285, including submergence-induced biotic stress-related genes. Our multifaceted transcriptome approach using the rice shoot base region illustrates a differential response to submergence between deepwater and nondeepwater rice. Jasmonic acid metabolism appears to participate in the submergence-mediated internode elongation response of deepwater rice.
水淹是限制植物生长和存活的环境因素。深水稻 () 通过快速伸长节间并使叶片保持在水面上方来适应水淹。我们对两个具有不同深水生长反应的品种的幼苗处于两个发育阶段的茎基部区域（包括基部节点、节间和茎尖）进行了比较 RNA 测序转录组分析。深水稻 cv C9285 和非深水稻 cv Taichung 65 之间的转录组比较显示，在水淹过程中，两种基因型之间存在相似和不同的表达模式。与赤霉素生物合成、海藻糖生物合成、厌氧发酵、细胞壁修饰和包括乙烯响应因子在内的转录因子相关的基因的表达在品种之间有显著差异。有趣的是，在两个品种中，茎基部的茉莉酸含量在水淹期间下降，而外源茉莉酸抑制了 cv C9285 中水淹诱导的节间伸长，表明茉莉酸在水稻的水淹反应中起作用。此外，靶向从头转录组装揭示了 cv C9285 特有的转录本，包括水淹诱导的生物胁迫相关基因。我们使用水稻茎基部区域的多方面转录组方法说明了深水稻和非深水稻对水淹的不同反应。茉莉酸代谢似乎参与了深水稻水淹介导的节间伸长反应。
