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BACK TO CHROMATIN. “Telomere-mediated activation of the DNA damage response appears to be intimately linked to the chromatin structure. Specifically, it was shown that chronic DNA damage from the processed telomeres also affects histone expression leading to their depletion and to the depletion of the central histone chaperones.” http://journal.frontiersin.org/article/10.3389/fgene.2013.00136/full View in LinkedIn

DIFFERENT HELPER CELL GROUPS. "Depending on their sex and their stage of development, plant reproductive cell lineages are associated with different supporting cell populations. In the stamen, male meiotic cells are invested by a layer of sporophytic (somatic) tapetal cells, which are essential for postmeiotic development and, particularly, the synthesis of the sporopollenin pollen wall and its coating." http://www.sciencedirect.com/science/article/pii/S1534580713000427 View in LinkedIn

TELOMERES AND DNA DAMAGE. “Telomere length is highly connected with the replicative lifespan of metazoan cells. Telomeres shorten with each successive round of DNA replication until one telomere reaches a threshold of “shortness” that emits a chronic DNA damage signal that causes the cell to cease dividing and enter senescence. Mechanistically, the short telomeres are seen as chronic DNA damage by the cell, resulting in the activation of the DNA damage response, which causes a G1 cell cycle arrest.” http://journal.frontiersin.org/article/10.3389/fgene.2013.00136/full View in LinkedIn

OUTSOURCED FUNCTIONS. "It is also evident that certain functions vital for protecting transgenerational genome integrity in animal germ cells, such as the suppression of transposition in the germ cell genome, has been partially “outsourced” to gametophytic helper cells in plants." (Targeted at suppressing parasitic mobile genetic elements by transposing silencing). http://www.sciencedirect.com/science/article/pii/S1534580713000427 View in LinkedIn

HUMAN ALU REPEAT. “Over 5% of the mammalian genome consists of short interspersed elements (SINEs), typified by the human Alu repeat. These are RNA polymerase III transcribed sequences whose expression is usually silenced. However, upon prolonged exposure to DNA damaging agents that predominantly cause double strand breaks, transcription from the human Alu elements and murine SINEs is strongly induced.” http://journal.frontiersin.org/article/10.3389/fgene.2013.00136/full View in LinkedIn

JOB DONE. “Thus, the forces of natural selection diminish after animals reach reproductive success because survival beyond that event has diminished value for the survival of the species. Energy is better spent on guaranteeing reproductive success than it is for increasing individual longevity. Thus, after reproductive success the forces of natural selection do not favor increased longevity. However, after reproductive success an animal has the potential to survive for a period of time determined by the level of excess physiological capacity reached at sexual maturation.” http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

EXCESS BUFFER. “Once animals reach sexual maturation and raise progeny to independence, the excess physiological capacity, like that engineered into a space vehicle, allows each to continue beyond the vital goal. The further longevity of each is determined by the excess capacity present at the time the goal was reached. In animals that goal, of course, is reproductive success.” http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

BUFFER SYSTEMS. “Greater, or redundant physiological capacity increases the likelihood for animal survival to reproductive success just as redundant vital systems in complex machines, like space vehicles, better insures that they will achieve their goals.” http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

REPRODUCTIVE DRIVE. “Species continuation depends on the survival of a sufficient number of members of that species to live long enough to reproduce and raise progeny to independence. This fundamental premise leads to the belief that the best way to insure that this occurs is for natural selection to favor those animals having greater physiological capacity in vital organs.” http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

REVERSE VIEW. “I would like to suggest an alternative hypothesis for the role of telomeres in aging. I propose that the shortening of telomeres in normal dividing cells is not an expression of aging, but rather an expression of longevity determination. The distinction between longevity determination and aging is significant.” http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn