Expression dynamics and functional roles of KLF4 during embryonic hair follicle development in cashmere goats

Cashmere, produced by the secondary hair follicles of cashmere goats, is known for its fineness, softness, and excellent heat retention properties. With the growing demand from the textile industry, improving both cashmere yield and quality has become an urgent challenge. Hair follicle development during the embryonic stage results from coordinated interactions between multiple cell types and tissue structures. Therefore, it is essential to elucidate the key regulatory factors and molecular mechanisms involved in hair follicle development in cashmere goats. In this study, transcriptome sequencing analysis of key developmental stages in embryonic cashmere goat skin revealed significant enrichment of the KLF family of transcription factors among differentially expressed genes. The expression of KLF4 was relatively low at embryonic day 75 and significantly increased by embryonic day 125. KLF4 was predominantly localized to the inner root sheath, hair bulb, and epidermal layer of the skin. Functional cell assays demonstrated that KLF4 overexpression suppressed proliferation, promoted apoptosis in secondary dermal papilla cells, and disrupted cell cycle progression. Further transcriptomic analyses and bioinformatic target gene prediction revealed a functional association between changes in KLF4 expression and alterations in Vdr expression, accompanied by modulation of Wnt/β-catenin signaling activity. These findings provide a potential theoretical basis for future molecular breeding strategies aimed at increasing follicle density and optimizing fiber quality.