Signaling Couples Hair Follicle Stem Cell Quiescence With Reduced Histone H3 K4/K9/K27me3 for Proper Tissue Homeostasis
April 2016
in “
Nature communications
”
TLDR Certain signals are important for reducing specific chemical markers on hair follicle stem cells during rest periods, which is necessary for healthy hair growth.
The study found that in adult mouse skin and hair follicle stem cells (HFSCs), levels of histone H3 K4/K9/K27me3 were actively reduced during the quiescent phase (G0) of the cells. This reduction in histone methylation did not correlate with changes in mRNA levels for specific genes during quiescence. The study also demonstrated that this hypomethylation state was necessary for the proper progression of the hair cycle. Inhibition of BMP signaling, which is known to prevent HFSC proliferation, resulted in increased histone methylation during quiescence, suggesting a link between signaling pathways and epigenetic regulation. Additionally, manipulating cultured skin epithelial cells to remove proliferation factors and add BMP4 led to a decrease in histone methylases and an increase in demethylases mRNA levels. The researchers concluded that signaling pathways are linked to the reduction of H3 K4/K9/K27me3 levels in HFSCs during quiescence, which is important for maintaining proper tissue homeostasis.
