Transcriptome-wide isolation and expression ofNF-Ygene family in male cone development and hormonal treatment ofPinus tabuliformis

It is known that nuclear factor Y (NF-Y) transcription factors play an important role in flowering time regulation and hormone response (ABA, GA) in angiosperms, but, little known in conifers. Moreover, theNF-Ygene family has not been comprehensively reported in conifers. Here, we identified 9NF-YA, 9NF-YBand 10NF-YCgenes inPinus tabuliformisusing Arabidopsis NF-Y protein sequences as queries. Additionally, by comparing conserved regions and phylogenetic relationships of the PtNF-Ys, we found that NF-Ys were both conserved and altered during evolution.PtTFL2,PtCO,PtNF-YC1andPtNF-YC4were exploited by expression profile in male cone development and correlation analysis. Furthermore, NF-YC1/4 and DPL (DELLA protein ofP. tabuliformis) were interacted by yeast two-hybrid and BiFC assays, which suggested thatNF-YC1/4may be involved in gibberellins signaling pathway. Moreover, the multiple types of phytohormones-responsivecis-elements (ABA, JA, IAA, SA) have been found, and gene expression profile analysis showed that manyNF-Ygenes responded positively to SA and as opposed to IAA and JA, revealing the potential role ofNF-Ysin conifers resistance. In summary, this study provided the basis for further investigation of the function ofNF-Ygenes in conifers.

Automated summary

NF-Y transcription factors play important roles in flowering time regulation and hormone response in angiosperms. This study identified NF-Y genes in Pinus tabuliformis and suggested their potential involvement in signaling pathways and resistance in conifers. The comprehensive investigation of NF-Y genes provides a basis for further exploration of their biological functions in conifers.