Burmese Python Genome Reveals Their Extreme Eating Abilities

The first complete and annotated snake genome of the Burmese python reveals that the reptile rapidly evolved a number of gene changes to deal with it metabolism and digestion.

Researchers from the University of Colorado, Denver , sequenced the genome of the Burmese python, one of the five largest snakes in the world. They discovered a number of rapidly evolved genes that are associated with extreme characteristics like increased metabolism and growth of internal organs.

"The bottom line is that snakes have undergone incredible changes at all levels of their biology, from the physiological to the molecular. Snakes appear to have functionally evolved much more than other species. They are a crucible of evolution," David Pollock, Associate Professor of Biochemistry and Molecular Genetics at the CU School of Medicine, said in a statement. "

Pollock along with fellow researcher Todd Castoe who is the lead author, discovered that the snakes bear a huge number of proteins, which the ancestors adapted in response to the extreme conditions.

"One of the fundamental questions of evolutionary biology is how vertebrates with all the same genes display such vastly different characteristics," said Castoe, a former postdoctoral fellow at the CU School of Medicine now at the University of Texas at Arlington. "The Burmese python is a great way to study that because it is so extreme. We'd like to know how snakes uses genes we all have to do things no other vertebrate can do."

The researchers noted that extreme characteristics in the snake that include rapid metabolism, shape of spine and skull and cell cycle regulations are all linked with positive selection in hundreds of genes.

Positive selections are rare and this is what makes the snakes extraordinary. Protein adaptation and rapid alteration in the genome structure gives the Burmese python an edge over other snakes with same genes.

Burmese python, the carnivorous nocturnal rainforest dweller, easily gulps its own sized birds and mammals. It attacks the prey using pointy teeth and wraps its body around the prey and kills it. They generally are found near human habitation and can even digest large preys like pigs and goats and even alligator and deer.

After feeding on prey, the gene expression of a Burmese python undergoes great changes that are linked with 35-100 percent size increase mainly the heart, kidney, liver and small intestine. These changes take place in a day or two. During this period the metabolism of the snake shoots highs.

"Genes that were fully off are now full on. Snakes eat animals as big as themselves. Once they catch something that size, they need to digest it quickly before it rots in their stomach, and they have to turn a lot of genes on to do it. What we are seeing now can apply to people," Pollock concluded. "We can link mutations to physiological effects and perhaps find a way to stop those mutations before they cause disease. There are any number of possibilities and we are only starting to unravel them."

The study published in the journal Proceedings of the National Academy of Sciences (PNAS) throws light on how evolution functions at molecular level.