Mu-Crystallin, Thyroid Hormone-Binding Protein, Is Expressed Abundantly in the Murine Inner Root Sheath Cells

The study identified μ-crystallin as a thyroid hormone-binding protein abundantly expressed in the inner root sheath cells of mouse hair follicles during the anagen phase of the hair growth cycle. The expression of μ-crystallin was localized to the cuticle layer and Huxley's layer of the inner root sheath, with increased mRNA levels during mid- and late anagen phases, and absent during catagen and telogen phases. The research suggested that μ-crystallin might play a structural role in hair follicle development and influence hair growth by modulating thyroid hormone availability, although its precise function in hair follicles needed further investigation.