Study on the function of gene in .

is an economically important woody oil crop in China, where seed oil quality and yield are critical determinants of commercial value. Although the WD40-repeat transcription factor is known to regulate plant secondary metabolism and development, its specific functions in remain uncharacterized. In this study, we isolated the gene from , which encodes a nuclear-localized protein (molecular weight 38.38 kDa, pI 5.0) sharing 99.71% sequence identity with . Heterologous expression resulted in: (1) significantly increased leaf trichome density (up to 114 trichomes/50 mm²); (2) enhanced seed anthocyanin accumulation (199-318% increase); and (3) substantial alterations in fatty acid composition, including 79% elevation in oleic acid (C18:1), 113% increase in gondoic acid (C20:1), 35% reduction in both linolenic (C18:3) and palmitic acids (C16:0), and 87% decrease in erucic acid (C22:1). Molecular analyses revealed that mediates these phenotypic changes through upregulation of trichome development-related genes (, , ), anthocyanin biosynthesis genes (, , ), and lipid metabolism genes (, ). These findings demonstrate the pleiotropic regulatory roles of in controlling key agronomic traits, establishing it as a valuable molecular target for genetic improvement of .