Mouse notch: expression in hair follicles correlates with cell fate determination.

The study investigated the role of cell-cell interactions in skin development, focusing on the mouse homolog of Notch (mNotch) and its expression in hair follicles. Researchers cloned mNotch and used double-labeled in situ hybridization to analyze its expression pattern during skin development. They found that high levels of mNotch are expressed in the epithelial compartment of hair follicles, particularly in matrix cells as they begin to differentiate into various cell types. mNotch mRNA expression was consistent throughout the hair follicle's growth phase and into the second hair cycle. The cells expressing high levels of mNotch were transitioning from mitotic precursors to differentiating cell types, separate from the inductive interactions with the dermal papilla. These findings suggest that mNotch plays a significant role in follicular differentiation and possibly in determining cell fate within the hair follicle.