Genome-Wide Identification, Characterization, and Expression Analysis of the NAC Transcription Factor Family in Sweet Cherry (Prunus avium L.)

The NAC (NAM, ATAF1/2, and CUC2) family is one of the largest plant-specific transcription factor families, playing a crucial role in adaptation to abiotic stresses. However, the <i>NAC</i> gene family in sweet cherry (<i>Prunus avium</i> L.) remains poorly understood. In this study, we identified 130 <i>NAC</i> genes (<i>PaNAC</i>) from the sweet cherry genome, which were unevenly distributed across eight chromosomes. Phylogenetic analysis classified the PaNACs into 21 distinct groups, including 2 sweet cherry-specific groups. Comparative analysis revealed significant variations in gene proportions, exon-intron structures, and motif compositions among different groups. Furthermore, cis-element analysis suggested the potential roles of <i>PaNACs</i> in regulating plant growth, development, hormone signaling, and stress responses. Transcriptomic data revealed tissue-specific expression patterns for several <i>PaNAC</i> genes. qRT-PCR further confirmed that eight selected <i>PaNACs</i> were responsive to various abiotic stresses in Gisela 6, a widely used hybrid rootstock in sweet cherry production that shares high sequence similarity in <i>NAC</i> genes with <i>P. avium</i>. These findings provide valuable insights for future research on the functional characteristics of the <i>PaNAC</i> genes in the growth, development, and responses to abiotic stress in sweet cherry.