Immunolocalization of Enzymes, Binding Proteins, and Receptors Sufficient for Retinoic Acid Synthesis and Signaling During the Hair Cycle
retinoic acid RA cellular retinol-binding protein retinol dehydrogenase retinal dehydrogenase 1 retinal dehydrogenase 2 retinal dehydrogenase 3 cellular RA-binding protein 2 hair follicle sebaceous gland interfollicular epidermis hair cycle epithelial-mesenchymal interactions Crabp2 RA receptors CRBP RDH RALDH1 RALDH2 RALDH3 CRABP2 skin
TLDR Retinoic acid production and signaling in hair follicles are regulated by location and timing, affecting hair growth and cycling.
The study investigated the localization of enzymes, binding proteins, and receptors involved in retinoic acid (RA) synthesis and signaling during the hair cycle in C57BL/6J mice. It found that the RA biosynthesis pathway, including cellular retinol-binding protein, retinol dehydrogenase, retinal dehydrogenase 1-3, and cellular RA-binding protein 2, was present in various layers of the hair follicle, sebaceous gland, and interfollicular epidermis in a hair cycle-dependent manner. This suggests that RA biosynthesis is regulated spatially and temporally within the hair follicle, influencing hair growth, differentiation, and cycling. The study also provided new insights into epithelial-mesenchymal interactions and the differentiation states within the RA pathway, as well as the nuclear versus cytoplasmic localization of Crabp2 and RA receptors.