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VERY STRANGE SYSTEM. "Imagine if you looked exactly like your grandmother but nothing at all like your mother. In fact, your mother would only have half of the genetic information that you have. While this seems very unrealistic, it's actually how many plants reproduce by using an alternating life cycle." https://lnkd.in/dUu-njs View in LinkedIn

TELOMERES AND AGING."Telomeres are the protective caps on the ends of chromosomes that affect how quickly cells age. They are combinations of DNA and protein that protect the ends of chromosomes and help them remain stable. As they become shorter, and as their structural integrity weakens, the cells age and die quicker." However, lifestyle may affect telomere activity.” http://www.ucsf.edu/news/2013/09/108886/lifestyle-changes-may-lengthen-telomeres-measure-cell-aging View in LinkedIn

FRAGMENT FROM NATURE these next two weekends deal with plants as alien creatures with confoundingly complex life styles, such as alternation of generations. Plants asexually make spores, which are single haploid cells (one set of chromosomes, n) that can make another plant when stuck in the ground. They also use sperm and egg to reproduce. But the two are linked: the sexual plant makes an asexual plant (n), and that in turn completes the cycle by making the sexual plant (2n), and each event makes a new generation, by alternating sexual and asexual reproduction. Weird. View in LinkedIn

SOMA VS STEM CELLS. “In mammals with a limited growth phase, telomerase activity in somatic tissues is restricted to stem cell derivatives with high proliferation potential. But other animals, like some fish, grow throughout their life with little senescence. All somatic cells require a high proliferation capacity and telomerase should be active in all cells, irrespective of fish age” http://onlinelibrary.wiley.com/doi/10.1016/S0014-5793(98)01020-5/full View in LinkedIn

NUCLEAR REPLICOMETER. “In early efforts to determine the location of the replicometer, early experiments in which the nuclei of old and young cultured cells were fused to the enucleated cytoplasm of opposite aged cytoplasts revealed that the replicometer was located in the nucleus.” http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

TICK TOCK. “Eukaryotic chromosome termini consist of telomeres, short sequence repeats. According to the telomere hypothesis, DNA replication leads to telomere shortening, resulting in a cellular mitotic clock. Telomerase resets it by telomere synthesis.” https://lnkd.in/dm7mtBZ View in LinkedIn

EVENT COUNTER MINIMA. “An intracellular counting mechanism must be present. These data included: 1) the Phase III Phenomenon itself; 2) our observation that cryogenically preserved cells "remember" at what doubling level they were preserved; and 3) the enormous literature describing hundreds of biological changes occurring in normal cells well before they lose their replicative capacity.” http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

REPLICOMETER. “The sought-after mechanism should not be called a clock or chronometer because these are devices used for the measurement of the passage of time. Because the replicative limit of normal cells is not directly the result of the passage of time but the number of DNA replications, the putative mechanism should be more properly referred to as an event counter.” http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

THE CELLULAR COUNTER for age, "the holy grail in cytogerentology. Because cell mortality and immortality are inextricably linked to aging and cancer, the importance of this goal would be difficult to exaggerate.” http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

IMPERCEPTIBLE AGING. “Animals that do not reach a fixed size in adulthood either do not age or the rate is undetectable. Fascinating recent findings reveal that in the rainbow trout (Oncorhynchus mykiss), an animal with imperceptible age changes, and unlike animals that do age, high telomerase activity has been found in the cells of all of the organs analysed.” https://lnkd.in/esfPTAR View in LinkedIn