组织再生依赖于干细胞分裂和增殖。但是, 我们对调控干细胞行为的基因和蛋白质知之甚少. 现在, Sarin等人发现telomerase 中的蛋白质成分, TERT, 在调控干细胞增殖中起重要作用。他们的工作揭示, 激活TERT 可导致头发滤泡干细胞的分裂和增殖, 造成头发迅速成长. 众所周知, telomerase保护染色体的末端, 进而在细胞老化中起关键作用. 现在的这一最新发现揭示了telomerase的另一重要功能: 调控干细胞增殖。
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Conditional telomerase induction causes proliferation of hair follicle stem cells
Kavita Y. Sarin1,3, Peggie Cheung1, Daniel Gilison1,3, Eunice Lee1, Ruth I. Tennen1,2, Estee Wang1, Maja K. Artandi1, Anthony E. Oro2,4 and Steven E. Artandi1,2
TERT, the protein component of telomerase1, 2, serves to maintain telomere function through the de novo addition of telomere repeats to chromosome ends, and is reactivated in 90% of human cancers. In normal tissues, TERT is expressed in stem cells and in progenitor cells3, but its role in these compartments is not fully understood. Here we show that conditional transgenic induction of TERT in mouse skin epithelium causes a rapid transition from telogen (the resting phase of the hair follicle cycle) to anagen (the active phase), thereby facilitating robust hair growth. TERT overexpression promotes this developmental transition by causing proliferation of quiescent, multipotent stem cells in the hair follicle bulge region. This new function for TERT does not require the telomerase RNA component, which encodes the template for telomere addition, and therefore operates through a mechanism independent of its activity in synthesizing telomere repeats. These data indicate that, in addition to its established role in extending telomeres, TERT can promote proliferation of resting stem cells through a non-canonical pathway. Source:Nature 436, 1048-1052 (18 August 2005) | doi: 10.1038/nature03836
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