Pan Ting, Sun Xiuqiang, Liu Yangxuan, Li Hui, Deng Guangbin, Lin Honghui, Wang Songhu
CAS Center for Excellence in Molecular Plant Sciences, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China.
Ministry of Education, Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, State Key Laboratory of Hydraulics and Mountain River Engineering, Sichuan University, Chengdu, 610064, China.
Plant Mol Biol. 2018 Feb;96(3):217-229. doi: 10.1007/s11103-017-0684-7. Epub 2017 Nov 24.
1599 novel circRNAs and 1583 heat stress-specific circRNAs were identified in Arabidopsis. Heat stress enhanced accumulation of circRNAs remarkably. Heat stress altered the sizes of circRNAs, numbers of circularized exons and alterative circularization events. A putative circRNA-mediated ceRNA networks under heat stress was established. Heat stress retards plant growth and destabilizes crop yield. The noncoding RNAs were demonstrated to be involved in plant response to heat stress. As a newly-characterized class of noncoding RNAs, circular RNAs (circRNAs) play important roles in transcriptional and post-transcriptional regulation. A few recent investigations indicated that plant circRNAs were differentially expressed under abiotic stress. However, little is known about how heat stress mediates biogenesis of circRNAs in plants. Here, we uncovered 1599 previously-unknown circRNAs and 1583 heat-specific circRNAs, by RNA-sequencing and bioinformatic analysis. Our results indicated that much more circRNAs were expressed under heat stress than in control condition. Besides, heat stress also increased the length of circRNAs, the quantity of circularized exons, and alternative circularization events. Moreover, we observed a positive correlation between expression patterns of some circRNAs and their parental genes. The prediction of ceRNA (competing endogenous RNA) networks indicated that differentially-expressed circRNAs could influence expression of many important genes, that participate in response to heat stress, hydrogen peroxide, and phytohormone signaling pathways, by interacting with the corresponding microRNAs. Together, our observations indicated that heat stress had great impacts on the biogenesis of circRNAs. Heat-induced circRNAs might participate in plant response to heat stress through the circRNA-mediated ceRNA networks.
在拟南芥中鉴定出1599个新型环状RNA（circRNA）和1583个热胁迫特异性circRNA。热胁迫显著增强了circRNA的积累。热胁迫改变了circRNA的大小、环化外显子的数量以及可变环化事件。建立了一个热胁迫下假定的circRNA介导的竞争性内源RNA（ceRNA）网络。热胁迫会抑制植物生长并使作物产量不稳定。已证明非编码RNA参与植物对热胁迫的响应。作为一类新发现的非编码RNA，环状RNA（circRNA）在转录和转录后调控中发挥重要作用。最近的一些研究表明，植物circRNA在非生物胁迫下差异表达。然而，关于热胁迫如何介导植物中circRNA的生物合成知之甚少。在这里，我们通过RNA测序和生物信息学分析，发现了1599个以前未知的circRNA和1583个热特异性circRNA。我们的结果表明，热胁迫下表达的circRNA比对照条件下多得多。此外，热胁迫还增加了circRNA的长度、环化外显子的数量以及可变环化事件。此外，我们观察到一些circRNA的表达模式与其亲本基因之间存在正相关。ceRNA网络预测表明，差异表达的circRNA可能通过与相应的微小RNA相互作用，影响许多参与热胁迫、过氧化氢和植物激素信号通路响应的重要基因的表达。总之，我们的观察结果表明热胁迫对circRNA的生物合成有很大影响。热诱导的circRNA可能通过circRNA介导的ceRNA网络参与植物对热胁迫的响应。
