Wed. Dec 1st, 2021


In 1961, Osamu Shimomura and Frank Johnson isolates a protein from jellyfish Bright green Under UV light. Corals, too, can fluoresce within a wide range of colors, thanks to similar proteins. Now scientists at Harvard University have genetically modified the three-banded panther worm to enable the animal to emit the same green tinge. New paper Published in the journal Developmental cell. Their hope is to unravel the mystery of rebirth.

Most animals show some kind of regeneration: hair regrowth, for example, or weaving a broken bone together. But some animals are particularly capable of amazing regenerative achievements, and studying the processes by which they accomplish these can have significant implications for human aging. If a salamander loses a leg, The limb will grow again, For example, when some geckos can detach their tails as a distraction to avoid predators and then re-grow them. Zebra fish can regenerate a lost or damaged fin, as well as repair damaged heart, retina, pancreas, brain or spinal cord. Cut a planarian flatworm, a jellyfish or a marine anemone in half and it will regenerate its whole body.

And then there’s the three-banded Panther Worm (Hofstenia miamia), A tiny creature that looks a lot like a thick grain of rice, has been named for its trademark trio of cream-colored stripes all over its body. If a panther worm is cut into three parts, each part will turn into a fully formed worm in eight weeks. These insects are found primarily in the Caribbean, the Bahamas and Bermuda, as well as in Japan, and they are voracious predators, if they are hungry enough and cannot find another prey, not to mention a few bites from their fellow panther worms. . They also offer a promising new model for studying the mechanics of regeneration.

Co-author Mansi Srivastava, an evolutionary biologist at Harvard University, has been studying the three-banded Panther Worm since 2010, when he was a postdoctoral scholar in Peter Raddian’s lab at the Whitehead Institute in MIT. They collected 120 or more worms in Bermuda and brought them back to Cambridge. Insects did not adapt immediately to laboratory life: Srivastava and Reddin had to find the right salinity level for their water and find an acceptable food source. The worms did not take care of the liver. Radian was feeding his planarian flatworms, and some took refuge in man-eaters to survive. Eventually, the researchers realized that panthers like insects Brian Shrimp (Aka Sea monkey), And the animals eventually began to improve and reproduce.

A 1960 report claimed that worms could reproduce their detached heads, but scientifically there was very little follow-up. Preliminary experiments by Radian and Srivastava prove that panther worms can not only regenerate their heads, they can regenerate any part of the body like the Planarian flatworm – although the two are only remotely related. Srivastava is now running his own laboratory at Harvard, researching the rebirth of Panther worms.

In 2019, Srivastava and his lab revealed the complete genome sequence of Panther Worm, as well as identified many of their “DNA switches” that appear to control genes for whole-body regeneration. Specifically, they identified a portion of the noncoding DNA that controls whether a type of “master control gene”, known as the initial growth response (EGR), has been activated for regeneration. EGR, in turn, can turn on or off other genes involved in various processes. If EGR is not activated, worm regeneration cannot occur.



Source link

By admin

Leave a Reply

Your email address will not be published. Required fields are marked *