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“AT THE INTERSECTION of non-coding transcription, DNA repair, chromatin structure, and cellular senescence. Recent paradigm-setting studies are now revealing that non-coding RNAs, other than microRNAs, also play intriguing roles in the maintenance of chromatin structure, in the DNA damage response, and in adult human stem cell aging.” http://journal.frontiersin.org/article/10.3389/fgene.2013.00136/full View in LinkedIn

JUNK DNA, REPEATS, TRANSPOSONS AND VIRAL ELEMENTS. “Over evolutionary time, viruses actively exchange genetic material with their host cells. However, just because a non-coding RNA expressed by a virus exhibits hallmarks of a known class of host cell non-coding RNAs does not mean that it necessarily functions comparably. Viruses are extremely clever at altering the bits of host cell genome that they acquire to meet their own needs.” https://lnkd.in/dD7FjZ4 View in LinkedIn

CONSERVED REPEATS. “The telomeres in human cells consist of thousands of repeats of the sequence TTAGGG. This sequence is remarkably conserved from primitive organisms to humans. The sequence is found in all invertebrates and in some trypanosomes and slime molds.” http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

TELOMERE METRICS. “Harley et al. observed that the mean telomere length decreased by 2 to 3 kilobase pairs (kbp) during the serial passage of several strains of normal human diploid fibroblasts. The decrease was found to be progressive and averaged 50 base pairs for each population doubling. The telomere shortening seen in aging normal human fibroblasts also occurs in vivo in skin epidermal cells, peripheral blood leukocytes and colon mucosa epithelia.” http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

REPETITIVE DNA. “Telomeres are structures found at the ends of linear chromosomes and consist of repetitive DNA sequences. Telomeres apparently prevent recombination and allow the attachment of chromosome ends to the nuclear envelope.” http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

DISORDER AND FINALITY. “The number of population doublings that a normal cell is capable of undergoing may be the in vitro demonstration of longevity determination. The molecular disorders that herald its approach are age changes. In vivo, these age changes lead to an increase in vulnerability to disease or pathology which results in death well before maximum longevity is reached.” http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

INCREASING MOLECULAR DISORDER. “It is because of these considerations that I propose that telomere shortening may be the molecular equivalent of longevity determination, not aging, and that the increasing molecular disorder that is known to occur in normal cells as telomeres shorten is equivalent to age changes. As indicated earlier hundreds of biological changes occur in normal cells as the age in vitro representing increasing molecular disorder and all compromise the internal milieu that ultimately leads to the Phase III Phenomenon.” http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

INEXORABLE ENTROPY. “The crucial suggestion is that the events that occur after reproductive success that fail to maintain the system and increase the likelihood of dying are called age changes. That is, there is an increase in molecular disorder for which repair processes increasingly fail to correct. The second law of thermodynamics applies, that is, entropy increases.” http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html View in LinkedIn

QUIET FREE-FALL. “The state of survival beyond reproductive success can be regarded as a period of "coasting" or "free-wheeling", that is, developmental processes have ended and the ability to maintain those systems declines.” http://protein.bio.msu.ru/biokhimiya/contents/v62/full/62111380.html 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