A lizard looks around as it climbs down a window screen
A lizard looks around as it climbs down a window screen in Encinitas, California October 8, 2008. Reuters/Mike Blake

Lizards have the unique ability to regenerate their tail; researchers have studied this ability and have found a way in which human beings can regenerate their limbs. Researchers from Arizona State University discovered the genetic recipe for lizard tail generation.

They studied the genes that turned on when the tail was regenerated in the green anole lizard (Anolis carolinensis). This lizard when caught by a predator loses its tail and then grows it back.

Lead author Kenro Kusumi, professor in ASU's School of Life Sciences and associate dean in the College of Liberal Arts and Sciences explained that lizards share the similar toolbox of genes in humans. They are the most closely related animals to humans "that can regenerate entire appendages." He stated that while regeneration nearly 326 genes in specific regions of the regenerating tail were activated, "including genes involved in embryonic development, response to hormonal signals and wound healing."

Even salamanders, frog tadpoles and fish regenerate their tails but they turn on genes only in the "Wnt pathway" but lizards have a tissue growth that is distributed throughout the tail and that is what makes the regeneration unique. Elizabeth Hutchins, a graduate student in ASU's molecular and cellular biology program and co-author of the paper said that the regeneration was a long process and did not happen overnight. Lizards take 60 days to regenerate their tail. "Lizards form a complex regenerating structure with cells growing into tissues at a number of sites along the tail," explained Hutchins.

Jeanne Wilson-Rawls, co-author and associate professor with ASU's School of Life Sciences stated that there was one particular type of cell that was extremely essential for tissue generation. Human beings have satellite cells that can grow and develop into skeletal muscles and other tissues, this very same cell is present in lizards as well.

"Using next-generation technologies to sequence all the genes expressed during regeneration, we have unlocked the mystery of what genes are needed to regrow the lizard tail," said Kusumi. The discovery can help humans regrow new cartilages, muscles or even spinal cords in the future. Providing new therapeutic approaches to healing injuries, birth defects, and treating diseases such as arthritis

The researchers hope their findings will help lead to discoveries of new therapeutic approaches to spinal cord injuries, repairing birth defects, and treating diseases such as arthritis.

This research was funded by grants from the National Institutes of Health and Arizona Biomedical Research Commission and the findings are published today in the journal PLOS ONE.