[Aging as a metagenetic process].
Genomes of eukaryotic cells are so complicated that spontaneous processes lead inevitably to a continuous formation of egoistic genetic elements from the normal ones. These elements convert the intracellular Cosmos into Chaos and therefore they can be named chaonogenes. They behave as endogenous genetic parasites and are able to evaluate. The rate of their evolution is very rapid, which unevitably results in senescence and death of not only cells and multicellular organisms but also of populations and species, because chaonogens are transmitted from somatic cells to gametes. Populations of chaonogenes are very sensitive to environmental changes, and different sets of intracellular or extracellular changes are commonly used in nature to put obstracles in deleterious evolution of chaonogenes or to stop their evolution. These changes can be moderate (as at mitosis) or crude (as at meiosis), or they can be predicted (as programmed biochemical changes in the course of mitosis, meiosis and gametogenesis) or unpredicred (mutations, somatic crossingover, random association of gamets), but in all the cases they lead eventually to some degree of rejuvenation. In somatic cell populations, the process of senescence in slowed down by means of epigenetically determined changes and mitotic divisions, at which both kinds of changes (programmed and accidental) are moderate, and for this reason only a small part of dividing cells dies. At meiosis both kinds of changes are so acute that the majority of cells die, but the formation of gametes and zygotes becomes almost completely rejuvenated. Only mutations leading to very acute changes in intracellular conditions (whose products act on chaonogenes similarly as new antibiotics on bacteria) can save aging populations of multicellular organisms from death (as do L. N. Gumilev's "mutations of passionarity"), and only accidentally appearing "catastrophic" macromutations can give rise to new (and, of the same time, young) species. It is concluded that the induction of acute temporal biochemical changes in the inner environment is to slow down processes of human senescence and to lead to rejuvenation.
Vakhmin
Iu B
IuB
Institute of Cytology RAS, St. Petersburg.
D016922:Cellular Senescence / Q000235:genetics*; D004247:DNA; D006801:Humans; D008540:Meiosis; D008938:Mitosis
D004247:DNA
Starenie kak metageneticheskiĭ protsess.