PtNF-Ys基因在油松花发育早期的表达与功能分析OA

To elucidate the causes of the long juvenile phase and low seed yield in Pinus tabuliformis seed orchards and explore the underlying regulatory mechanisms,this study focused on the flowering-related genes during early stages of flower bud differentiation.The aim was to reveal the gene expression characteristics during this period and clarify the biological functions of the nuclear factor Y(NF-Y)family members.Transcriptome sequencing(RNA-seq)was performed on apical meristems collected from adult trees in the Wucheng National Seed Orchard of P.tabuliformis,Shanxi,China,from mid-July to mid-October.The results revealed that the expression levels of PtNF-YB8 and many other NF-Y genes increased significantly in mid-October.Multiple cis-elements,including gibberellin(GA)-responsive and light-responsive elements,were found within the PtNF-YB8 promoter.Furthermore,exogenous GA treatment of apical buds significantly up-regulated the expression level of PtNF-YB8.Subcellular localization assays in tobacco cells showed that the PtNF-YB8 protein was localized in both the cytoplasm and the nucleus.Heterologous overexpression of PtNF-YB8 in Arabidopsis resulted in a distinct delayed flowering phenotype.Yeast two-hybrid assays confirmed that PtNF-YB8 interacts with PtNF-YC9 and PtNF-YC10.In conclusion,PtNF-YB8 may function by forming complexes with NF-Y members,such as PtNF-YC9/10,to facilitate signal transduction and negatively regulate flowering time.These findings provide a theoretical basis for elucidating the flowering regulatory network in conifers and developing techniques for high and stable yields in seed orchards.