毛竹PhcircRNA1的鉴定和调控通路分析

Identification and Regulatory Pathway Analysis of PhcircRNA1 in Phyllostachys edulis

环状RNA(circRNAs)是一类经过反向剪切后,3′末端和5′末端共价结合形成的闭合环状单链非编码RNA,在环境胁迫下对植物生长发育有着重要调控作用。为探索circRNA在毛竹响应胁迫过程中的调控作用,本研究构建了circRNA-miRNA-mRNA调控通路。在分析毛竹的全转录组测序数据后,选择并鉴定了1个在紫外线胁迫(UV)和高温胁迫(42℃)下均差异表达的circRNA(PhcircRNA1),并利用生物信息学分析其调控的miRNA和靶基因。通过核糖核酸酶R(RNase R)法鉴定其转录的稳定性,并通过实时荧光定量PCR(qRT-PCR)方法分析了PhcircRNA1、靶miRNA(Ph-miR156)和靶mRNA的表达特征。本研究进一步选择GLR3.1(Glutamate Receptor–Like Gene 3.1)靶基因作为研究对象,观察毛竹水培苗根尖生长至1 cm后的circRNA-miRNA-mRNA表达调控趋势。结果表明,在UV胁迫和高温胁迫下,PhcircRNA1和靶mRNA表达量都有明显下降趋势,而miRNA表达量增高。在毛竹根尖细胞中,PhcircRNA1和GLR3.1表达量变化一致,和Ph-miR156相反。结果表明PhcircRNA1可能通过竞争性内源RNA(ceRNA)机制参与毛竹非生物胁迫响应,并在毛竹生长发育中起重要作用。本研究为进一步研究PhcircRNA1的功能奠定了理论基础。

Circular RNAs(circRNAs)are unique type of noncoding RNAs,it has closely circled by 3′and 5′end covalent ligase through reverse alternative splicing(AS).The circRNA plays an important role in responses to environmental stress influencing plant growth and development.In this study,we constructed a circRNA-miRNA-mRNA regulatory pathway,and explored the regulatory role of circRNA in response to stress in bamboo.After analyzing the transcriptome data of Phyllostachys edulis,a circRNA(PhcircRNA1)differentially expressed under both UV stress and high temperature stress(42℃)was screened and identified,and its regulated miRNA and target genes were analyzed by bioinformatic method.Stability of its transcription was analyzed by Ribonuclease R(RNase R)and the expression pattern of PhcircRNA1,target miRNA(PhmiR156)and target mRNA was validated by quantitative real time PCR(qRT-PCR).Furtherly,one of target gene,GLR3.1(Glutamate Receptor–Like Gene 3.1)was selected as the research interest,and the regulation trend of circRNA-miRNA-mRNA expression in root tip with the length of more than 1 cm of Moso bamboo hydroponic seedlings were investigated.The results indicated that under UV stress and high temperature,the expression of PhcircRNA1 and target mRNA decreased significantly,while the expression of miRNA increased.However,the expression pattern of PhcircRNA1 and GLR3.1 in root tips were the same,which was inverse to that of Ph-miR156.These findings provide hints that PhcircRNA1 may participate in response to abiotic stress in moso bamboo through the competitive endogenous RNA(ceRNA)mechanism and play a crucial role in the growth and development of moso bamboo.This study laid a foundation for further research on the function of PhcircRNA1.