Identification of NF-Y gene family members and expression analysis during fruit development in Prunus persica

Nuclear factor Y （NF-Y）， also known as heme activator protein （HAP） or CCAAT-binding factor （CBF）， plays pivotal roles in plant growth and development. However， systematic studies on the NF-Y gene family in peach （Prunus persica） remain scarce. The NF-Y gene family members were identified from the genome-wide data of peach cultivar "Zhongyou 14"， and comprehensive bioinformatics analyses were performed on their phylogenetic relationships， chromosomal distribution， protein physicochemical properties， and gene structures. Furthermore， the expression profiles of PpNF-Y genes at different fruit developmental stages of "Zhongyou 14" were examined using quantitative real-time PCR （qRT-PCR）. A total of 24 PpNF-Y gene family members were identified in the peach genome， unevenly distributed across eight chromosomes， encoding proteins of 121-366 amino acids. These members were classified into three subfamilies， all of which contained conserved NF-Y motifs. Expression analysis revealed thatthe 24 PpNF-Y genes exhibited differential expression patterns during fruit development in the peach cultivar "Zhongyou 14". Among them， PpNF-YA4， PpNF-YA9， and PpNF-YB8 showed a biphasic expression trend， with transcript levels initially increasing and then decreasing. Fourteen genes， including PpNF-YA3， displayed a continuous decline in expression throughout fruit development. In contrast， PpNF-YC2 and PpNF-YC3.2 were significantly up-regulated at the later stages of fruit development. Meanwhile， four genes， including PpNF-YA7， exhibited no significant changes in expression levels across the entire fruit developmental period. These findings provide a foundation for further studies on the functional roles of these genes in peach fruit ripening.