Abstract

Non-coding RNAs are a class of RNAs with multiple roles in plant life. Covalently closed circular RNA molecules (circRNAs) have been recently shown to be a group of RNA isoforms that show widespread tissue-specific expression in plants, often cooperating with the corresponding linear mRNAs to regulate gene function. However, no previous study of poplar has identified circRNAs in the cambium and determined their potential roles in the cambium or xylem development. In the present study, we sequenced RNAs in the cambium of poplar seedlings at two developmental stages, and identified and characterized 4912 circRNAs. Alternative back-splicing circularization events for 87 genes were identified among the circRNAs derived from different chromosomes. A total of 1138 circRNAs originated from 928 host genes, which were classified among the three major functional categories by GO analysis. Thirty-nine circRNAs were differentially expressed between cambium samples of stems at two developmental stages. Twenty-four DEcircRNAs interacted with 98 miRNAs as targets, of which some were associated with cambium growth and development. The results suggest that circRNAs play important roles in the cambium in relation to the regulation of stem growth and development in poplar seedlings.

中文翻译：

---

杨树幼苗发育中茎干中circRNAs的鉴定与鉴定

摘要

非编码RNA是一类在植物生命中具有多种作用的RNA。最近，共价闭合的环状RNA分子（circRNA）被证明是一组RNA亚型，在植物中表现出广泛的组织特异性表达，通常与相应的线性mRNA协同调节基因功能。然而，以前的杨树研究尚未发现在形成层中的circRNA，并确定了它们在形成层或木质部发育中的潜在作用。在本研究中，我们在两个发育阶段对杨树幼苗形成层中的RNA进行了测序，并鉴定和表征了4912个circRNA。在衍生自不同染色体的circRNA中鉴定出87个基因的其他反向剪接环化事件。共有1138个来自928个宿主基因的circRNA，通过GO分析将其划分为三个主要功能类别。39个circRNA在两个发育阶段的茎形成层样品之间差异表达。24个DEcircRNA与98个miRNA作为靶标相互作用，其中一些与形成层的生长和发育有关。结果表明，circRNAs在形成层中起着重要的作用，与杨树幼苗茎生长的发育有关。