‘凤丹’牡丹PoFD基因克隆及表达分析

Cloning and Expression Analysis of PoFD Gene from Paeonia ostii ‘Fengdan’

Flowering Locus D(FD)基因属于bZIP转录因子家族,与FT基因相互作用,在促进植物开花等方面发挥重要作用。本研究以‘凤丹’牡丹为材料,基于‘凤丹’三代全长转录组测序结果,采用RT-qPCR技术克隆PoFD基因,并进行生物信息学和表达模式分析。结果表明,克隆到的PoFD基因含有一个2 712 bp完整的ORF框,编码903个氨基酸。PoFD蛋白分子式为CHNOS,理论等电点(pI)为4.88,为亲水蛋白,无跨膜结构,二级结构中无规则卷曲和α-螺旋所占比例较高,β-转角仅占少部分。荧光定量分析发现,PoFD基因在叶片中表达量最高,推测PoFD基因可能主要作用于叶片调控牡丹花期。牡丹不同花发育时期,PoFD基因在半开期的表达量较高,推测PoFD基因在‘凤丹’开花的中期发挥功能。不同浓度油菜素内酯(brassinosteroids,BR)激素喷施处理下,‘凤丹’牡丹花期具有不同程度的延迟,并且PoFD基因的表达均有所下降,表明PoFD基因可能响应BR调控牡丹花期。本研究为进一步研究PoFD基因在牡丹花期调控中的作用提供理论参考。

Flowering Locus D(FD)gene,a member of the bZIP transcription factor family,plays an important role in promoting plant flowering interacting with the FT gene via interaction with FT gene.In this study,tree peony(Paeonia ostii)variety ‘Fengdan’ was used as the material,the PoFD gene was cloned by RT-qPCR technology based on the results of the three-generation full-length transcriptome sequencing of ‘Fengdan’,and the bioinformatics and expression patterns analysis were performed on it.The results showed that the cloned PoFD gene contained a 2 712 bp complete ORF frame,encoding 903 amino acids.The molecular formula of PoFD protein is CHNOS,and the theoretical isoelectric point(pI)is 4.88.It is a hydrophilic protein and has no transmembrane structure.There are a high proportion of random coils and α-helices in secondary structure,while β-turns account for only a small part.RT-qPCR analysis demonstrated the expression of PoFD gene was the highest in leaves,thus speculating that PoFD gene may mainly function in leaves to regulate the flowering stage of tree peony.In different flower development stages,the expression of PoFD was the highest at the half-open stage,inferring that the PoFD gene may play the role at the middle flowering stage.Compared with the control group,the flowering stage of ‘Fengdan’ delayed at varying degrees while treated with varied concentrations of brassinosteroid(BR),and the expression of PoFD gene decreased,indicating that PoFD gene may regulate tree peony flowering period in response to BR.This study provides a theoretical reference for the follow-up study of the role of PoFD gene in the regulation of tree peony flowering.