Genome-Wide Identification and Analysis of WD40 Family and Its Expression in F. vesca at Different Coloring Stages

Abstract

WD40 proteins play important roles in the synthesis and regulation of anthocyanin, the regulation of plant morphology and development, and the response to various abiotic stresses. However, the role of WD40 in Fragaria vesca (F. vesca) has not been studied. In this study, a total of 216 FvWD40 family members were identified, which were divided into four subfamilies based on evolutionary tree analysis. Subcellular localization predictions show that FvWD40 family members are mainly localized in chloroplasts, nuclei, and cytoplasm. An analysis of collinearity revealed a total of eight pairs of intraspecific collinearity of the FvWD40 gene family, and interspecific collinearity showed that the FvWD40 gene family covaried more gene pairs with Arabidopsis thaliana (Arabidopsis) than with rice (Oryza sativa). Promoter cis-acting elements revealed that the FvWD40 gene family contains predominantly light, hormone, and abiotic stress response elements. Tissue-specific expression analysis showed that a number of members including FvWD40-111 and FvWD40-137 were highly expressed in all tissues, and a number or members including FvWD40-97 and FvWD40-102 were lowly expressed in all tissues. The FvWD40 gene family was found to be expressed at all four different coloring stages of F. vesca by qRT-PCR, with lower expression at the 50% coloring stage (S3). FvWD40-24, FvWD40-50, and FvWD40-60 showed the highest expression during the white fruit stage (S1) period, suggesting that these genes play a potential regulatory role in the pre-fruit coloring stage. FvWD40-62, FvWD40-88 and FvWD40-103 had the highest expression at the 20% coloration stage (S2), and FvWD40-115, FvWD40-170, FvWD40-184 and FvWD40-195 had the highest expression at the full coloration stage (S4). These results suggest a potential role for these genes during fruit coloration. This study lays a foundation for further research on the function of the WD40 gene family.