Cao Xibing, Fan Guoqiang, Cao Lin, Deng Minjie, Zhao Zhenli, Niu Suyan, Wang Zhe, Wang Yuanlong
Institute of Paulownia, Henan Agricultural University, No 95 Wenhua Road, Jinshui Area, Zhengzhou, 450002 Henan People's Republic of China ; College of Forestry, Henan Agricultural University, No 95 Wenhua Road, Jinshui Area, Zhengzhou, 450002 Henan People's Republic of China.
Genes Genomics. 2017;39(1):77-86. doi: 10.1007/s13258-016-0473-8. Epub 2016 Oct 20.
Drought stress adversely affects plant productivity. Growth and timber production of Paulownia trees are limited under drought stress. Changes in gene expression patterns and miRNA in different ploidy of have been investigated. However, the responses of to drought stress at the microRNA (miRNA) level have not been reported so far. To identify miRNA candidates and their target genes involved in the drought stress response in diploid and tetraploid , four small RNA and four degradome libraries from diploid and autotetraploid under normal and drought stress conditions were constructed and sequenced. A total of 41 conserved and 90 novel miRNAs were identified. Among these miRNAs, 67 (26 conserved and 41 novel) and 53 (six conserved and 47 novel) were significantly differentially expressed in response to drought stress in diploid and autotetraploid , respectively. Degradome analysis identified 356 candidate miRNA target genes that encoded proteins with functions that included plant defense, transcriptional regulation, and hormone metabolism. In particular, miR4 and miR156 were identified only in autotetraploid under drought stress. These results will help us build a foundation for future studies of the biological functions of miRNA-mediated gene regulation in .
干旱胁迫对植物生产力产生不利影响。在干旱胁迫下，泡桐树的生长和木材产量受到限制。人们已经研究了不同倍性泡桐中基因表达模式和miRNA的变化。然而，迄今为止，泡桐在干旱胁迫下miRNA水平的响应尚未见报道。为了鉴定参与二倍体和四倍体泡桐干旱胁迫响应的miRNA候选物及其靶基因，构建并测序了来自正常和干旱胁迫条件下二倍体和同源四倍体泡桐的4个小RNA文库和4个降解组文库。共鉴定出41个保守miRNA和90个新miRNA。在这些miRNA中，二倍体和四倍体泡桐中分别有67个（26个保守miRNA和41个新miRNA）和53个（6个保守miRNA和47个新miRNA）在干旱胁迫下显著差异表达。降解组分析鉴定出356个候选miRNA靶基因，这些基因编码的蛋白质具有植物防御、转录调控和激素代谢等功能。特别是，miR4和miR156仅在干旱胁迫下的同源四倍体泡桐中被鉴定出来。这些结果将有助于我们为今后研究泡桐中miRNA介导的基因调控的生物学功能奠定基础。
