Superpower Research

An article in the NY Times, Seeking Superpowers in the Axolotl Genome, discusses a regenerative amphibian, the Axolotl. Also known as the Mexican walking fish, this salamander has the capability of regrowing most of its body parts. While some animals are able to regenerate to some degree, these little guys are almost limitless. Jeremiah Smith, an associate professor from the University of Kentucky states, "as long as you don't cut off their heads, they can grow back a nearly perfect replica of just about any body part, including up to half of their brain". This is why researchers are working on improving maps of their DNA. These creatures can only be found in canals in the far south of Mexico City due to habitat degeneration and imported fishing. However, captive axolotl are thriving in laboratories. Unlike most amphibians, these salamanders reach sexual maturity and spend their lives as large tadpole babies. Their genome is about ten times the size of that of a human, however, a team of researchers have published in Genome Research the most complete assembly of DNA yet. Dr. Keinath and her colleagues mapped more than 100,000 pieces of DNA on chromosomes making this the largest genome to be assembled at this level. They used an approach referred to as linkage mapping, which relies on trend that DNA sequences that are physically close together on a chromosome tend to be inherited together. Using such technique, axolotls and their close relatives, tiger salamanders were crossed to track patterns of gene inheritance. The researchers were able to identify the axolotls' sequences of DNA and where they sat along the 14 chromosomes. This data is providing information for the process of human regenerative medicine.

Regeneration of the body is a fascinating and useful capability. More research into this ability would be positive because it could eventually lead to regenerative human, or other species who lack this feature, medicine. If humans were able to regenerate body parts, it could have a detrimental impact. The ability to regenerate could cut back on health care costs because transplants may be lessened, it could prolong life or improve the quality of life.

Decoding the Axolotl genome: Insights into tissue regeneration

In biology salamanders have become a model for evolutionary and developmental studies. In this study it focuses on one salamander, which is the Mexican axolotl (Ambystoma mexicanum). They choose this salamander in particular because they are known for their ability to regenerate body parts. If this salamander looses a body part, within weeks the limb will grow back with, muscles, bones, and tissue. To understand regenerate and why it is very limited in most species, scientists need to have access to genome data. In the Axolotl due to their size, there are 32 billion base pairs, which is 10x larger than the human genome.


International team of researchers have now assembled, annotated, and sequenced the complete axolotl genome, which is the largest genome to ever be decoded. They did this using the PacBio-platform, which a sequencing technology that produces long reads to span large repetitive regions. Those who analyzed the assembled genome discovered many features that seem to point uniqueness of the axolotl. It was also discovered that an essential development gene named PAX3 is completely missing from the genome and it function has been taken over by another genome named PAX7. Both of these genes play a key role in muscle and neural development.

https://www.sciencedaily.com/releases/2018/01/180124131716.htm

https://www.mpg.de/11886639/decoding-the-axolotl-genome