Regulation of Keratin Gene Expression in Hair Follicle Differentiation

The study from 1991 investigated the regulation of keratin gene expression during hair follicle differentiation, focusing on the transcriptional activation of 50-100 keratin genes as follicle bulb cells differentiate into cortical or cuticle keratinocytes. Researchers isolated genes from several conserved gene families and used in situ hybridization to examine expression patterns, revealing distinct transcriptional hierarchies in different cell types. They identified conserved sequence motifs in keratin gene promoter regions that may determine cell specificity. The study also found conserved DNA motifs and expression patterns in sheep and human cuticle keratin genes, and demonstrated that regulatory DNA elements and proteins of hair keratin genes are functionally conserved across mammals, as evidenced by the expression of sheep wool follicle genes in transgenic mice.