Phospholipase C-δ1 Is an Essential Molecule Downstream of Foxn1, the Gene Responsible for the Nude Mutation, in Normal Hair Development

The study investigated the role of phospholipase C-δ1 (PLC-δ1) in hair development, particularly in relation to the Foxn1 gene, which is responsible for the nude mutation in mice. Researchers found that both PLC-δ1 knockout mice and nude mice exhibited similar hair abnormalities, such as lack of cuticle and bending, due to decreased expression of hair keratins. The study demonstrated that PLC-δ1 is a crucial molecule downstream of Foxn1, as its expression was induced in Foxn1-transfected cells and was significantly reduced in the skin of nude mice. The impaired activation of PLC downstream effectors in these mice further supported the conclusion that insufficient expression of PLC-δ1 leads to hairlessness in nude mice.