基因＂配方＂ z-bo 2020-08-18 620

　　By understanding the secrets of how lizard tails can regenerate, researchers may be able to develop methods to stimulate the regeneration of human limbs. A research team at Arizona State University took one step closer to solving this puzzle. Scientists have discovered the genetic "secret recipe" for tail regeneration in lizards, which can be attributed to the ability to use genetic ingredients to mix together in appropriate amounts.

　　An interdisciplinary research team used a new generation of molecular and computer analysis tools to study the genes that initiate tail regeneration. The team studied the green chameleon lizard (Anolis carolinensis). When it is hunted by predators, it often breaks its tail and then grows back.

　　"Basically, lizards and humans share the same toolbox genes," said lead author Kenro Kusumi, a professor at Arizona State University's School of Life Sciences, who is also the associate dean of the Free School of Arts and Sciences. "Lizards are the animals most closely related to humans. They can regenerate entire appendages (such as tails). We found that they activate at least 326 genes in the specific region of tail regeneration, including those involved in embryonic development, hormone signal response and wound healing. Gene."

　　Other animals, such as newts, tadpoles and fish, can regenerate their tails, but most of them grow on the top. During tail regeneration, they all activate genes in the so-called "Wnt signaling pathway", which is a process required to regulate stem cells in many organs, including the brain, hair follicles and blood vessels. However, lizards have a unique tissue growth pattern, which is distributed throughout the tail.

　　"Regeneration is not an instantaneous process," said Elizabeth Hutchins, co-author of the paper and a graduate student in the Molecular and Cell Biology Program at Arizona State University. "In fact, it takes more than 60 days for a lizard to regenerate a functional tail. The lizard forms a complex regeneration structure that allows cells to grow into tissues along multiple points of the tail."

　　"We have identified a cell type that is extremely important for tissue regeneration," said Janet Wilson-Rawls, co-author of the paper and associate professor in the Arizona State University School of Life Sciences. "Just like mice and humans, lizards also have satellite cells that can develop into tissues such as skeletal muscle."

　　"Using next-generation technology to sequence all genes expressed during regeneration, we have solved the mystery of what genes are needed for lizard tail regeneration," Kusumi said. "By discovering the genetic secret of lizard regeneration, and then using the same genes in human cells, it is possible in the future to grow new cartilage, muscle, and even spinal cord."

　　Researchers hope their findings will help develop new ways to treat spinal cord injuries, repair birth defects, and treat diseases such as arthritis.