Study Of The Relationship Between The Expressions Of Telomere Related Factors And Cell Replicative Senescence

Cellular senescence is one of the important cellular processes in life. Understanding of the origin and regulation mechanism of senescence is useful to recognize our life and deal with aging related disease. Recent investigations indicated that telomere shortening leads to normal cell senescence. The length of telomere is controled by telomere-related factors. The study of the relationship between telomere-related factors and cell replicative senescence contributes to elucidate the mechanism of aging.Cellular replicative senescence has been defined by Hayflick as the ultimate and irreversible loss of replicative capacity in human primary diploid fibroblasts culture after a reproducible number of population doublings(PD). There are good arguments to see this process as a cellular model for aging. Human embryo lung fibroblasts (HEL) characteristic replicative senescence, due to the fact that HEL is a kind of diploid fibroblasts. Thus HEL will be a good model to mimick cell replicative senescence.More and more novel telomere-related factors have been identified, and they regulate the length and the conformation of telomere. For example TRF1 can regulate POT1 binding to telomeric ssDNA, whereas Tankyrasel can regulate the binding of TRF1 to telomeric dsDNA. They play important role in the process of cell replicative senescence. The role of those factors in cell senescence and regulation of telomere length and structure has been well defined inthe tumor cells. However, how they function in the cell replicative senescence of normal cells is still unclear. Moreover hTR is an important component of telomerase. hTR is expressed in normal cells although the telomerase activity is absent in those cells, implying that hTR might be involved in other processes such as cell senescence. In this study, the relationship between...