Programming gene expression in developing epidermis

摘要: As the major proteins of adult keratinocytes, keratins provide biochemical markers for exploring mouse epidermal embryogenesis. Here, we used a modified method whole-mount in situ hybridization to track skin-specific expression endogenous keratin mRNAs throughout To monitor transcriptional regulation, coupled this with beta-galactosidase human promoter-driven transgene. These studies have radically changed our perception how program gene becomes established during development. Specifically, discovered that (1) basal (K5 and K14) genes are first detected at E9.5 highly regional fashion, surprisingly as early single layered ectodermal stage; (2) patterns do not correlate morphogenesis per se, but rather variations embryonic origin underlying mesenchyme, supporting morphogenetic criteria inductive cues mesenchymal; (3) expressed periderm, notion layer arises from stratification, even though it is simple epithelial-like morphology subsequently sloughed development; (4) later K5 K14 parallel proliferative capacity stratification; (5) K1 K10 E13.5, their differentiation stratification. led us explore whether potential regulators these similarly. We show AP2 (but Sp1) cRNAs hybridize pattern similar to, preceding cRNAs. Finally, using cultured cells, demonstrate has strong effect on cellular environment does normally possess activity.