| First Author | Nakajima T | Year | 2013 |
| Journal | J Invest Dermatol | Volume | 133 |
| Issue | 2 | Pages | 354-60 |
| PubMed ID | 22931914 | Mgi Jnum | J:196486 |
| Mgi Id | MGI:5488568 | Doi | 10.1038/jid.2012.293 |
| Citation | Nakajima T, et al. (2013) Roles of MED1 in quiescence of hair follicle stem cells and maintenance of normal hair cycling. J Invest Dermatol 133(2):354-60 |
| abstractText | MED1 (mediator complex subunit 1) is expressed by human epidermal keratinocytes and functions as a coactivator of several transcription factors. To elucidate the role of MED1 in keratinocytes, we established keratinocyte-specific Med1-null (Med1(epi-/-)) mice using the K5Cre/LoxP system. Development of the epidermis and appendages of Med1(epi-/-) mice were macroscopically and microscopically normal until the second catagen of the hair cycle. However, the hair cycle of Med1(epi-/-) mice was spontaneously repeated after the second telogen, which does not occur in wild-type (WT) mice. Hair follicles of Med1(epi-/-) mice could not enter anagen after 6 months of age, resulting in sparse pelage hair in older Med1(epi-/-) mice. Interfollicular epidermis (IFE) of Med1(epi-/-) mice was acanthotic and more proliferative than that of WT mice, whereas these findings were less evident in older Med1(epi-/-) mice. Flow cytometric analysis revealed that the numbers of hair follicle bulge stem cells were reduced in Med1(epi-/-) mice from a few months after birth. These results suggest that MED1 has roles in maintaining quiescence of keratinocytes and preventing depletion of the follicular stem cells. |
