Turritopsis Nutricula
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Nature and Science 2010;8(2) Turritopsis nutricula Hongbao Ma, Yan Yang Brookdale University Hospital and Medical Center, Brooklyn, New York 11212, USA [email protected]; [email protected] Abstract: Turritopsis nutricula is a hydrozoan that can revert to the sexually immature (polyp stage) after becoming sexually mature. It is the only known metazoan capable of reverting completely to a sexually immature, colonial stage after having reached sexual maturity as a solitary stage. It does this through the cell development process of transdifferentiation. This cycle can repeat indefinitely tha offers it biologically immortal. It is not clear if stem cells are involved in this immortality or not. Upto now, there is little academic report in the Turristopsis nutricula studies. To study the mechanism of the biological immortality of Turritopsis nutricula possibly supplies the way finding the biological immortality for human. [Nature and Science 2010;8(2):15-20]. (ISSN: 1545-0740). Keywords: immortal; immortality; sexual maturity; stem cell; transdifferentiation; Turritopsis nutricula 1. Introduction occurs in parts of the organsism, like in the eye of the Turritopsis nutricula is a hydrozoan that can revert salamander. However, the immortal jellyfish has to the sexually immature (polyp stage) after becoming incorporated transdifferentiation into its lifecycle. In sexually mature. It is the only known metazoan capable the process, all of the old cells are regenerated. At the of reverting completely to a sexually immature, end of the cycle, the immortal jellyfish is a young colonial stage after having reached sexual maturity as a polyp, ready to start life anew (Wendy, 2009). solitary stage. It does this through the cell development While colonial animals can have their immortality, process of transdifferentiation. This cycle can repeat solitary animal individuals are to die. Hydrozoan indefinitely that offers it biologically immortal. To cnidarians usually have a complex life cycle, wherein a study the reason of the biological immortality of colonial stage leads to the sexually mature, solitary, Turritopsis nutricula possibly supplies the way finding adult stage. Eggs and sperms from solitary, sexual, the biological immortality for human. adult medusa (jellyfish) develop into an embryo and Turritopsis nutricula is a species of jellyfish with a planula larva, and they then form the colonial polyp very unusual quality: it is biologically immortal. Also stage. Medusae are formed asexually from polyps. known as the immortal jellyfish, this fascinating animal, These medusae have a limited lifespan and die shortly in theory, has the ability to sustain life indefinitely, so after releasing their gametes. long as its nerve center remains intact. The hydrozoan Turritopsis nutricula is diferent, Typically, jellyfish die after reproducing, but the which is biological immortality. The solitary medusa of immortal jellyfish is capable of returning to a polyp this species can revert to its polyp stage after becoming after producing offspring. This essentially means that sexually mature (Bavestrello et al., 1992; Piraino et al., this type of jellyfish is able to return itself to a much 1996). In the laboratory, 100% of these medusae younger state. As a result of reversing its life cycle, the regularly undergo this change. The cells that immortal jellyfish can evade death. If the jellyfish accomplish the building of a new stolon are probably continues to reverse its life cycle following those of the exumbrella. However, it is not known reproduction, it can live on for an indefinite period. In whether the sensory cells, myoepithelial cells, and laboratory tests, the species reverted back to the cnidocytes are derived from the exumbrella or the immature polyp stage 100% of the time. endodermal component. Turritopsis nutricula is capable of rejuvenating In the past, because of men’s desire to be forever itself due to a process called transdifferentiation. young, inspired by legends, epics, myths, stories of the Transdifferentiation occurs when a non-stem cell turns gods and goddesses, they engaged in the quest for the itself into another type of cell. But, it is not clear if so-called ‘fountain of youth’ but nobody was able to stem cells are involved in this immortality or not. As find one. Based on scientific studies, some organisms my opinion, the transdifferentiation in Turritopsis or creatures are considered or thought to be immortal. nutricula has related mechanism to stem cell when the As the nature will, to live eternally is an extracting life cycle reverted. It is important to reveal the dream in all the human history. Stem cell is the original relationship of this Turritopsis nutricula of life tissue and all adult cells come from stem cells transdifferentiation and stem cell. Transdifferentiation (Hongbao Ma 2005a). Germline stem cell is the cell in is rare, and when it does occur, it most commonly the earliest of the cell stage. It is possible to inject the http://www.sciencepub.net 15 [email protected] Nature and Science 2010;8(2) germline stem cell into adult human body to get the cells. After sexually reproducing, the jellyfish eternal life (Ma Hongbao 2007). However, the reveal reabsorbs all of its external parts and turns into a cyst, of the transdifferentiation mechanism of the jellyfish which looks like an ameba-esque blob. The cyst then Turritopsis nutricula will offer the chance to explore attaches to the ground and grows into a stalk-shaped the possibility of the eternal life for human. polyp colony. These polyps begin a new cycle, where they form into mature jellyfish - all genetically 2. Description identical. This specimen of Turritopsis nutricula Diameter of Turritopsis nutricula is about 5 mm. It vibrantly shows its majestic being, with its deep red has an equally high and bell-shaped figure. The walls stomach clearly showing. are uniformly thin. The bright red, big stomach has a cruciform shape in its cross section. Young specimens 2.1 Turritopsis nutricula have only 8 tentacles along the edge, while adult Classification specimens have 80-90 tentacles. Kingdom – Animalia Turritopsis nutricula is the first case in which a Phylum – Cnidaria metazoan is capable of reverting completely to a Class – Hydrozoa sexually immature, colonial stage after having reached Order – Hydroida sexual maturity as a solitary stage (Gilbert, 2006). Family – Clavidae Jellyfish usually die after propagating but Genus – Turritopsis Turritopsis nutricula reverts to a sexually immature Species – T. nutricula stage after reaching adulthood and is capable of rejuvenating itself. The jellyfish and its reversal of the Turritopsis nutricula is a Hydrozoan, which is a ageing process is now the focus of research by marine class of Cnidarians including the Portuguese Man-of- biologists and geneticists. It is thought to achieve the War, Hydra, and freshwater jellyfish. Hydrozoans are, feat through the cell development process of for the most part, colonial animals. Turritopsis transdifferentiation, in which cells transform from one nutricula is a colonial organism as a polyp, though it is type to another. an independent, pelagic creature. The organism has a The switching of cell roles is usually seen only diameter of 5 millimeters, or one fifth of an inch. when parts of an organ regenerate. However, it appears Although a young specimen would only have 8 to occur normally in the Turritopsis life cycle (Lech tentacles, an adult would have between 80 and 90 Mintowt-Czyz, 2009). tentacles. It has an obvious red stomach in the center of Turritopsis nutricula, a type of jellyfish, is gaining the main part of its body. Once eggs are fertilized, they notoriety for its uncanny and unprecedented capacity to develop in the stomach and in the screen formed by the de-evolve instead of dying. These jellyfish are the first cave in the planula, or free-swimming, ciliated form of evidenced metazoan, or multi-celled creature, to some Cnidarian species. The eggs must then be demonstrate the ability to revert back to a colonial deposited on the seabed in colonies of the larval stage stage after reaching sexual maturity. After sexually of polyps. The jellyfish will then hatch in 2 days and reproducing, most animals inevitably die. Turritopsis will become sexually mature after just 2 weeks, which nutricula, however, undergo a transformation in which it then can revert back to a polyp in the process of they return to a stage of sexual immaturity after transdifferentiation. T. Nutricula can be found reproducing, only to mature and reproduce again, then worldwide. return to sexual immaturity, and so on. What does this mean? Turritopsis nutricula do not die, by nature, and 2.2 Hydra are believed to have an indefinite potential lifespan. Classification: Turritopsis nutricula are about 5 mm in diameter in Kingdom – Animalia sexually mature stage. They have 8-24 tentacles when Phylum – Cnidaria they are young and up to 90 tentacles as mature adults. Class – Hydrozoa Shaped like a bell, their external walls are transparent Subclass – Leptolinae and their stomachs are large and have a distinctive red Order – Anthomedusae color. Suborder – Capitata Turritopsis nutricula rejuvenate from sexually Family – Hydridae mature to colonial through two processes: cell Genus – Hydra transformation and cell transdifferentiation. Transdifferentiation is one cell transform into a 3. Distribution, range and related species completely different type of cell. By Turritopsis nutricula are originally from the transdifferentiating, these cells are able to change their Caribbean but have spread all over the world. entire make-up, much like the much-publicized stem Turritopsis nutricula are found in temperate to tropical http://www.sciencepub.net 16 [email protected] Nature and Science 2010;8(2) regions in all of the world's oceans. It is believed to be spreading across the world as ships are discharging 3.6 Hydra viridissima ballast water in ports. Since the species is immortal, the The Green Hydra or formally called Hydra number of individuals is spiking. "We are looking at a viridissima can be found in both temperate and tropical worldwide silent invasion" said Smithsonian Tropical fresh waters.