Co-Expression Pattern of Artemis Serine 516 Phosphorylation with Indicators Involving in Differentiation, Proliferation and Apoptosis of Human Anagen Hair Follicles: An Immunofluorescence Double-Staining Study.

Abstract

Artemis belongs to the SNM1 gene family, and plays a role in repairing ionizing-radiation-induced DNA double-strand breaks and variable (diversity) joining recombination. S534, S538, S516, S645 represent four most rapid phosphorylation sites in Artemis, and serine phosphorylation at amino acid 516 is closely associated with activation. Artemis mutation is perceived as contributing to Omenn syndrome, which manifest features of severe combined immunodeficiency disease, associated with lymphadenopathy, hepatosplenomegaly, erythroderma and baldness. In addition, Artemis phosphorylated at serine 516 (Artemis S516-P) was expressed in scalp hair follicles (HF) as well as other skin appendages, and its expression level is important to mouse hair cycling. However, whether Artemis participated in the regulation of HF growth still unclear. Using immunofluorescence double-staining, we assessed the association between Artemis S516-P with proliferation, apoptosis, and differentiation markers in normal adult anagen scalp HF. The results of double-staining immunofluorescence revealed overlapping expression pattern for Artemis S516-P and keratin16, similar pattern for c-myc and p21, while presenting opposite trends for keratin 10, phospho-p53, Bax, Bcl-2 and keratin 14. Our study provides the clues that Artemis may play roles in regulation of differentiation, proliferation, apoptosis and cell cycling during HF growth and development.