Expression of Hex During Feather Bud Development

The study investigated the expression of the Hex/Prh gene during feather bud development in chick embryos. Hex mRNA was initially detected in the dorsolateral ectoderm and mesenchyme at 5 days, later localizing to the placode and underlying dermis. Hex protein was found in both the epidermis and dermis, with immunoelectron microscopy showing its presence in the nuclei and cytoplasm during the short bud stage. The expression pattern of Hex in the epidermis was similar to Wnt7a, a key player in feather follicle development, but differed in the dermis, indicating Hex's significant role in initiating feather morphogenesis.