Trichohyalin

Trichohyalin is a protein that plays a crucial role in the structure and function of hair. It is primarily found in the innermost layer of the hair follicle, known as the inner root sheath. Trichohyalin is involved in the process of keratinization, which is the formation of the tough, fibrous protein keratin that makes up hair.

Structure and Function

Trichohyalin is a large protein that consists of multiple repeating units called filaggrin repeats. These repeats are rich in amino acids such as serine, histidine, and glutamine. The filaggrin repeats in trichohyalin are responsible for its ability to bind to keratin filaments, helping to stabilize the structure of the hair shaft.

Trichohyalin also plays a role in the formation of the hair cuticle, which is the outermost layer of the hair shaft. It helps to organize the keratin filaments within the cuticle cells, providing strength and protection to the hair.

Role in Hair Growth

During the growth phase of the hair cycle, known as anagen, trichohyalin is synthesized and deposited in the inner root sheath cells. As the hair shaft elongates, trichohyalin is gradually incorporated into the hair cuticle, contributing to its structure and integrity.

Clinical Significance

Mutations in the gene encoding trichohyalin have been associated with certain hair disorders. For example, mutations in the trichohyalin gene have been found in individuals with Netherton syndrome, a rare genetic disorder characterized by abnormal hair growth, skin inflammation, and impaired skin barrier function.

See Also

• Hair follicle
• Keratinization
• Netherton syndrome