Runx3 Is Involved in Hair Shape Determination

The study demonstrated that the Runx3 gene played a significant role in hair shape determination by influencing mesenchymal/epithelial interactions during hair follicle development. Runx3 was expressed in the dermal papilla and dermal sheath throughout the hair cycle and in various skin appendages. Runx3 null mice exhibited a less dense pelage with more prominent outer guard hairs and a significant reduction in zigzag hairs, which were also shorter and had fewer bends. The study concluded that Runx3 influenced hair shape and structure, particularly affecting auchene and zigzag hair types, likely due to its role in the mesenchymal compartment of the hair follicle. The findings suggested potential interactions between Runx3 and Sox18 and highlighted the involvement of the BMP pathway in hair follicle morphogenesis and differentiation.