Genome-wide analysis of the GRF gene family their expression profiling in peach (<i>Prunus persica</i>)

Growth-regulating factors (GRFs) are plant-specific transcription factors with vital roles in multiple biological processes. Although GRFs have been identified in various plant species, a comprehensive analysis of <i>GRF</i> genes in peach (<i>Prunus persica</i>) has not yet been reported. In this study, 10 <i>PpGRF</i> genes distributed on 6 chromosomes were identified in peach genome and their properties were analyzed systematically. Expression pattern analysis suggested that most <i>PpGRFs</i> were preferentially expressed in young tissues. Multiple types of cis-elements were observed in PpGRF promoters, and <i>PpGRFs</i> positively respond to ultraviolet B-rays (UVB) and gibberellin (GA) treatments at the transcriptional level. Also, the content of gibberellic acid 3 (GA₃) and indole-3-acetic acid (IAA) changed significantly after UVB irradiation. <i>PpGRF 3</i>, <i>4</i>, <i>5</i>, <i>6</i>, <i>7</i>, <i>9</i> and <i>10</i> positive responses to UVB and GA₃ signals. The evolutionary patterns and expression profiles of PpGRFs detected in this study increase understanding of the important roles in peach.