Turritopsis dohrnii (immortal jellyfish)
Turritopsis dohrnii, commonly known as the "immortal jellyfish," is a unique species of jellyfish capable of regenerating its cells in response to life-threatening situations, allowing it to revert to its juvenile form and restart its life cycle. Discovered in the Mediterranean Sea in 1883, its remarkable ability to reverse aging was only recognized in the 1990s. This process, referred to as transdifferentiation, enables the jellyfish to transform specialized cells into different types, akin to a butterfly reverting to a caterpillar. The adult Turritopsis dohrnii is small, reaching only about 0.18 inches (4.5 mm) in size, with distinct features such as a nearly transparent body and bright red stomachs.
While this jellyfish's regenerative capabilities hold significant interest for scientific research—particularly in the fields of stem cell biology and potential medical applications for human health—Turritopsis dohrnii remains vulnerable to predators, especially before reaching sexual maturity. Researchers continue to explore the mechanisms behind its unique life cycle and regenerative processes in hopes of unlocking secrets that could inform treatments for diseases and enhance our understanding of aging. Despite its extraordinary abilities, the Turritopsis dohrnii exemplifies the delicate balance of life in the marine ecosystem.
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Turritopsis dohrnii (immortal jellyfish)
The Turritopsis dohrnii is a type of jellyfish that can regenerate its cells when faced with a life-threatening crisis, earning it the nickname "immortal jellyfish." After reaching adulthood, the organism can revert to its earliest stage of development in response to physical damage or starvation and begin its life cycle again. The process may be compared to a butterfly transforming back into a caterpillar or a chicken turning back into an egg and hatching again. The species was discovered in the Mediterranean Sea in 1883, but its ability to reverse aging was not observed until the 1990s. Scientists have continued to study the creature in hopes of replicating the process to determine how to recycle damaged cells in the human body and cure diseases such as cancer.
Life Cycle
Turritopsis dohrnii has also been referred to as the "Benjamin Button jellyfish" (after the short story and subsequent film character who ages backward). It develops from a fertilized egg into a planula (larva). The planula attaches to the ocean floor, where it grows into a blob-like state known as a polyp colony. The polyps form into free-swimming medusae that reach the adult stage in a few weeks. Fully grown Turritopsis dohrnii are tiny, the size of a human pinky nail at about 0.18 inches (4.5 mm). They have bright red stomachs that can be seen through their nearly transparent bell-shaped bodies. They also have dozens of white tentacles that outline their bodies.
When Turritopsis dohrnii is physically harmed or facing starvation, it can survive through a unique process known as transdifferentiation. It has a "rebirth" and transforms back to the beginning of its life cycle as a polyp. In the span of a few weeks, the polyp releases medusae that are genetically identical to the original jellyfish. During this process, the jellyfish absorbs its cells and then recycles them into other types of specialized cells, such as turning muscle cells into nerve cells. Despite their ability to regenerate, Turritopsis dohrnii are very fragile and often fall victim to predators. The transdifferentiation process only occurs after the jellyfish has reached sexual maturity, leaving it vulnerable before that stage.
Importance to Science
The process of transdifferentiation is important to scientists and researchers because it is identical to the process that occurs in human stem cells. During transdifferentiation, an adult cell, which is specialized for a particular type of tissue, can transform into a different type. By harnessing this power, scientists could essentially replace damaged cells with new cells and possibly affect the aging process and cure disease. While scientists have been studying Turritopsis dohrnii for several decades, they still do not know exactly how it ages in reverse. They continue to study the species as well as the potential for transdifferentiation in other jellyfish.
Bibliography
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