巴戟天实时荧光定量PCR内参基因的选择

Selection of reference genes for quantitative real-time PCR in Morinda officinalis

目的选择合适的内参基因,用于巴戟天不同组织和不同处理的叶中目标基因表达量的分析检测。方法以巴戟天不同组织和不同处理的叶为材料,根据巴戟天转录组数据,选择甘油醛-3-磷酸脱氢酶(GAPDH)、细胞色素P450(cytochrome P450,CYP)、微管蛋白α(tubulinalpha,TUA)和肌动蛋白(Actin)基因等10个内参基因作为候选基因。利用实时荧光定量技术,并结合geNorm、NormFinder和BestKeeper等软件分析内参基因的表达稳定性,从而筛选出巴戟天不同组织和不同处理叶中表达稳定的内参基因。选择合适的内参基因对巴戟天的1-脱氧木酮糖-5磷酸合成酶(DXS)和1-脱氧-D-木酮糖-5-磷酸还原异构酶(DXR)基因在不同组织和不同处理的叶中相对表达量进行分析。结果内参基因GAPDH和泛素(UBQ)在巴戟天不同组织中表达最稳定,GAPDH+UBQ的双内参组合能够更加准确地分析目的基因在巴戟天不同组织的相对表达量,而在不同处理的叶中GAPDH和Actin表达稳定性最好,选择GAPDH+Actin的双内参组合可以确保目的基因相对分析表达结果的可靠性。在巴戟天不同组织中,DXS目的基因的相对表达量为根<茎<叶,DXR的相对表达量为茎<根<叶。在巴戟天不同处理的叶中,DXS和DXR基因的相对表达量相对于未处理的叶(CK)都有所提高。结论筛选得到的稳定内参基因为后续巴戟天相关基因表达研究奠定基础,使用2个稳定内参的组合对目的基因进行均一化处理有利于提高目的基因表达分析的准确性。

Objective To select the appropriate reference genes for calibrating the quantitative real-time PCR detection of gene expression in different tissues and leaves with different treatments of Morinda officinalis. Methods With different groups and different processing leaves of M. officinalis as materials, 10 internal genes, including GAPDH, CYP, TUA, Actin and so on, were selected as candidate genes according to the M. officinalis transcriptome data. The expression stability of internal reference genes was analyzed by using real-time fluorescence quantification technique combined with software such as ge Norm, Norm Finder and Best Keeper, so as to select stable reference genes in different tissues and leaves of M. officinalis with different treatments. Finally, appropriate internal reference genes were selected to analyze the relative expression levels of DXS and DXR genes in different tissues and leaves with different treatments. Results Internal reference genes GAPDH and UBQ were the most stable in different tissues of M. officinalis, the double internal reference combination of GAPDH + UBQ can more accurately analyze the relative expression levels of target genes in different tissues of M. officinalis, while the most stable reference genes in leaves with different treatments were GAPDH and Actin;The selection of the double reference combination of GAPDH + Actin can ensure the reliability of the target gene expression results. In different tissues of M. officinalis, the relative expression of DXS target gene was in sequence of root < stem < leaf, while the relative expression of DXR was stem < root < leaf. The relative expression levels of DXS and DXR genes in leaves with different treatments were increased compared with those untreated leaves(CK). Conclusion The selected stable internal reference genes lay a foundation for the subsequent study on the expression of related genes of M. officinalis. Using the combination of two stable internal references to homogenize the target genes is conducive to improving the accuracy of the analysis of the expression of target genes.