Washington, December 15 (ANI): In a research on muscle development in pigs, scientists have found a previously unknown gene that has evolved a function in placental mammals, namely, enabling domestic pigs to develop more muscle and store less fat than their wild ancestor, the wild boar.
Researchers at Uppsala University, Swedish University of Agricultural Sciences and Broad Institute carried out the research.
They discovered a previously unknown gene ZBED6 that is unique to placental mammals.
The gene originates from a so-called jumping gene that integrated in the genome of a primitive mammal at least 150 million years ago and has since then evolved an essential function.
The function enabled domestic pigs to develop more muscle and store less fat than their wild ancestor, the wild boar.
"This is a result of the systematic selection that has been ongoing the last 60 years to breed pigs that produce the lean meat the consumers prefer," said Leif Andersson who led the study.
"This explains why a pork chop today contains much less fat compared with the pork chops produced a hundred years ago," he added.
Some years ago, Leif Andersson and his colleagues discovered a specific mutation in a non-coding DNA sequence that regulates the expression of an important growth factor, IGF2.
This mutation contributes very significantly to the difference in muscle growth between pigs and wild boars. "We have now in collaboration with researchers at the Broad Institute used a sophisticated molecular method to isolate the protein that binds the DNA sequence that is altered in pigs," said Lin Jiang, one of the PhD students associated with the project.
"Surprisingly, the protein is previously unknown and we named it ZBED6. The protein is present in all placental mammals including humans," he added.
The ZBED6 ancestor integrated in the genome of a primitive mammal at least 150 million years before present.
It has since then been domesticated and is now stably integrated in the genome at the same position in all placental mammals.
"Our finding that the DNA-binding parts of the protein are 100 percent identical among all mammals that we have investigated including humans shows that ZBED6 must have evolved an essential function," said Lin Jiang.
The results presented today show that ZBED6 does not only regulate the expression of the IGF2 growth factor in pig muscle, but appears to regulate hundreds if not thousands of other genes n mammals. (ANI)