Hydrocortisone modulates the expression of c-ets-1 and 72 kDa type IV collagenase in chicken dermis during early...

At the onset of chicken feather morphogenesis, dermal cells migrate along bundles of collagen fibers to colonize areas where bud outgrowth takes place. Chicken embryos treated with hydrocortisone during the critical phase of dermal rearrangement show featherless skin areas in which the dermis exhibits an increase of interstitial collagen. We had previously demonstrated that c-ets-1 is a nuclear transcription factor expressed in the dermis at the beginning of feather morphogenesis. Here we study, by in situ mRNA hybridization, the expression of c-ets-1 in the dermis of chicken embryos treated with hydrocortisone. We found that, among the two distinct products (p54 and p68) encoded by the chicken c-ets-1, the expression of the p68 product increased while expression of p54 decreased after hydrocortisone treatment. Since Ets-1 regulates matrix-metalloproteinases genes, we analyzed the expression of the 72 kDa type IV collagenase in both normal and hydrocortisone-treated embryos. We demonstrated that 72 kDa type IV collagenase mRNA expression decreased in the dermis after hydrocortisone treatment and that its expression correlated with that of p54c-ets-1. Taken together, these results indicate that hydrocortisone modulates c-ets-1 expression. In addition, they raise the interesting possibility that c-ets-1 might be involved in an altered pattern of feather development mediated by the accumulation of collagen due to a decrease in collagenase activities.