Genome-wide analysis of OFP gene family in pepper (Capsicum annuum L.)

Abstract

Ovate family proteins (OFPs) are transcriptional inhibitors that regulate plant growth and development and play important roles in the synthesis of secondary cell walls during pollen development. This study identified the pepper <i>OFP</i> gene family based on the genome-wide analysis and used bioinformatics methods to provide a fundamental profile of the gene family. 74 <i>OFP</i> genes with typical Ovate domain were identified in cultivated pepper Zunla-1, wild pepper Chiltepin and CM334. Chromosome mapping revealed that <i>CazOFP</i> genes were unevenly distributed on 11 chromosomes and Chr00 in Zunla-1, <i>CacOFP</i> genes on 12 chromosomes in Chiltepin, and <i>CamOFP</i> genes on 12 chromosomes and two Scaffflods in CM334. Gene structure analysis revealed that <i>CaOFP</i> genes possessed 1-3 exons, and the analysis of physicochemical properties suggested that <i>CaOFP</i>s were hydrophilic. Many <i>cis</i>-acting elements were identified in the promoter region of <i>CaOFP</i> genes, including ABRE, ARE, Box 4, G-box, TC-rich, and TCT-motif. The expression patterns of pepper at different growth stages showed that <i>CaOFP</i> genes were actively involved in the growth and fruit development of pepper, and <i>CazOFP16</i> and <i>CazOFP17</i> were actively involved in response to multiple hormones and stress events. qRT-PCR was also used to verify the expression of <i>CazOFP</i> gene in two developmental stages of seven pepper varieties with different fruit shapes, and it was found that <i>CaOFP</i> genes may be involved in the formation of fruit type in pepper. This study provides theoretical and practical evidence for future research on the <i>OFP</i> gene family.