Molecular Elements of the Regulatory Control of Keratin Filament Modulator AHF/Trichohyalin in the Hair Follicle
July 2008
in “
Experimental Dermatology
”
keratin filament AHF trichohyalin THH hair follicle ubiquitin-dependent proteolysis hair cycle growth phase resting phase bone morphogenetic protein-4 BMP-4 keratinocytes nuclear lamin C lamin A degradation mechanical strength hair shaft expression RT-PCR western blotting adenovirus infection epidermal keratinocytes keratin hair growth hair loss protein degradation hair strength gene expression PCR protein analysis virus infection skin cells
TLDR The study concluded that a protein important for hair strength is regulated by certain molecular processes and is affected by growth phases.
The study from January 12, 2009, conducted by Sachiya Yamamoto and colleagues, explored the regulation of AHF/trichohyalin (THH), a key protein in keratin filament assembly in hair follicles. They discovered that AHF, the mouse equivalent of human THH, is regulated by ubiquitin-dependent proteolysis and is abundant during the growth phase of the hair cycle but decreases during the resting phase. Bone morphogenetic protein-4 (BMP-4) was found to promote the transcription of THH in human keratinocytes. Additionally, the study revealed that nuclear lamin C, but not lamin A, is crucial for protecting THH from degradation. These findings suggest that the mechanical strength of the hair shaft is influenced by AHF/THH, with BMP-4 enhancing its expression and lamin C preventing its degradation. The research involved cellular and molecular experiments, not human subjects, and used techniques such as RT-PCR, western blotting, and adenovirus infection in normal human epidermal keratinocytes with sample sizes of n = 3 for quantitative data.
