Scientists have discovered organisms with cells that can live “forever”.
A free-living, ciliated protozoa called Tetrahymena thermophilia has cells that are immortal.
Check it. Decoding Immortality
“The Fountain of Youth may have just been discovered, not in a Florida spring, but in a murky Australian pond. Far from myth, the findings of Nobel Prize-winning scientist Elizabeth Blackburn, an enzyme that can keep cells young, may just prove to be the key to immortality.” –Smithsonianchannel
Smithsonian Channel “Decoding Immortality” Narration
For da Nerdz:
Check it. Tetrahymena extract protects Paramecium from oxygen-free radicals
“Cells of Paramecium tetraurelia will age and die, while cells of Tetrahymena thermophilia are immortal. Both are free-living, ciliated protozoa. Whole cells and homogenates of both Paramecium andTetrahymena were treated with iron(+2) to induce peroxidation of membrane lipids and other cellular constituents. Paramecium is far more susceptible to such peroxidative damage than Tetrahymena. Indeed, addition of Tetrahymena extract protects Paramecium from peroxidative damage. Tetrahymena’s protective molecules block the initial attack of oxygen-free radicals on Paramecium constituents.” –AGE@springerlink.com
Photo Credit: CDC/Dr. L.L. Moore, Jr.
Check it. The Telomere Lengthening Mechanism in Telomerase-Negative Immortal Human Cells Does Not Involve the Telomerase RNA Subunit
“According to the telomere hypothesis of senescence, the progressive shortening of telomeres that occurs upon division of normal somatic cells eventually leads to cellular senescence. The immortalisation of human cells is associated with the acquisition of a telomere maintenance mechanism which is usually dependent upon expression of the enzyme telomerase. About one third of in vitro immortalised human cell lines, however, have no detectable telomerase but contain telomeres that are abnormally long. The nature of the alternative telomere maintenance mechanism (referred to as ALT, for Alternative Lengthening of Telomeres) that must exist in these telomerase-negative cells has not been elucidated.” –Oxfordjournals
Of Interest
How Stress Affects Our Telomeres (Chromosome / DNA)
Check it. Hayflick limit
“The Hayflick limit (or Hayflick Phenomenon) is the number of times a normal cell population will divide before it stops replicating due to the telomeres shortening to a critical length.
The Hayflick limit was discovered by Leonard Hayflick in 1961,at the Wistar Institute, Philadelphia, when Hayflick demonstrated that a population of normalhuman fetal cells in a cell culture divide between 40 and 60 times. It then enters a senescence phase (refuting the contention by Alexis Carrel that normal cells are immortal). Each division (mitosis) shortens the telomeres on the DNA of the cell. Telomere shortening in humans eventually makes cell division impossible, and it is presumed to correlate with aging. This mechanism appears to prevent genomic instability and the development of cancer.”
Check it. Schrodinger’s Dance
“At every given moment our body is undergoing cellular division, known as mitosis. To replace old cells, new cells grow, cells in our organs are replaced, our hair, our skin, our tissues, repaired and renewed, cells are replicating and dividing. replicating and dividing. replicating and dividing. Replicating and dividing.”