Scientists have found out what prevents one of the jellyfish species from aging. Article about it published in PNAS.
Jellyfish have two life forms. They are born as drifting larvae, then attach themselves to the seafloor and develop into sprout-like polyps. Bottom dwellers clone themselves, forming tight colonies that develop into free-swimming jellyfish of the usual type. But the immortal jellyfish Turritopsis dohrniican reverse this cycle. They turn into amorphous bodies from which polyps grow and thus avoid dying of old age.
Maria Pascual-Torner of the University of Oviedo in Spain and her colleagues sequenced the genome of this jellyfish to elucidate the genetic mechanisms that allow “eternal” life. They found that the immortal jellyfish had twice as many copies of genes associated with DNA repair and protection. These copies can produce more protective and reparative proteins. The jellyfish also had unique mutations that prevent the destruction of telomeres, the ends of chromosomes that slow cell division and shorten the body as it ages.
Then, to determine exactly how T. dohrnii When it returns to its polyp form, scientists have found which genes are active during this reverse metamorphosis. They found that the jellyfish suppresses developmental genes, returning cells to their original state, and activating other genes that allow newly formed cells to re-specialize.
The study’s authors hope that the genes they discovered may also play a role in human aging. Thus, possibly in the future, scientists will be able to develop a “cure” for old age.