Shuai Peng, Su Yanyan, Liang Dan, Zhang Zhoujia, Xia Xinli, Yin Weilun
College of Biological Sciences and Technology, National Engineering Laboratory of Tree Breeding, Beijing Forestry University, China.
College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China.
FEBS Lett. 2016 Oct;590(20):3616-3627. doi: 10.1002/1873-3468.12419. Epub 2016 Oct 4.
Phased, secondary, small interfering RNA (phasiRNA) perform essential biological functions in plants. However, limited information is available on the role of phasiRNA genes in Populus (poplar), especially during drought stress. In this study, we identified 20 PHAS loci generating 91 phasiRNA in the genome of the model forest tree Populus trichocarpa (P. trichocarpa; western balsam-poplar) using the control and drought libraries. Our analysis indicated that six PHAS (PtPHA14-20) initiated by two Populus-specific miRNAs (miR6445 and miR6427) were specific to Populus. In addition, a total of 47 phasiRNA were found to be drought responsive, and five of them were confirmed by RT-qPCR. The phase cleavage of three PHAS loci by miRNA, and degradation of nine transcript targets by phasiRNA were experimentally confirmed based on degradome data. The identification of these Populus phasiRNA will contribute to a better understanding of their function and regulation during drought stress.
阶段性次级小干扰RNA（phasiRNA）在植物中发挥着重要的生物学功能。然而，关于phasiRNA基因在杨树中的作用，尤其是在干旱胁迫期间的作用，目前可用信息有限。在本研究中，我们利用对照文库和干旱文库，在模式林木毛果杨（P. trichocarpa；西部香脂杨）的基因组中鉴定出20个PHAS位点，这些位点产生了91种phasiRNA。我们的分析表明，由两种杨树特异性miRNA（miR6445和miR6427）启动的6个PHAS（PtPHA14 - 20）是杨树特有的。此外，共发现47种phasiRNA对干旱有响应，其中5种通过RT - qPCR得到证实。基于降解组数据，通过实验证实了miRNA对3个PHAS位点的切割以及phasiRNA对9个转录本靶标的降解。这些杨树phasiRNA的鉴定将有助于更好地理解它们在干旱胁迫期间的功能和调控。
