Some of the new miRNAs identified by researchers could explain the diversity in behavior and appearance among dog breeds produced by the domestication process. Photo by John Angelillo/UPI | License Photo
Nov. 20 (UPI) -- How has the domestication process impacted the evolution of gene regulation among dogs, cows, pigs, rabbits and other tamed animals? That's the question researchers at the Earlham Institute are trying to answer.
Specifically, geneticists at Earlham set out to measure the abundance and distribution of miRNAs in different tissue types among domesticated animals.
MicroRNAs, or miRNAs, are small non-coding RNA molecules that regulate gene expression inside the cells of plants, animals and some viruses.
MiRNA molecules are the reason why millions of cells distributed throughout the body, each with essentially the same exact genetic coding, can form a wide variety of tissue types and preform a diversity of biological functions.
"The evolution of different miRNAs in different species might lead to important changes in how genes are used and controlled," Earlham researcher Luca Penso-Dolfin said in a news release. "These modifications, which might happen both in space (different tissues) and time (for example, different developmental stages) are still not fully understood. Further research is needed to better clarify the role of miRNAs in the evolution of mammalian gene regulation."
For the new study, scientists surveyed miRNAs present in the different tissue types -- brains, testicles, hearts and kidneys -- of five different domesticated anime. Researchers compared the survey results to an miRNA database to isolate which microRNA molecules are relatively "new."
Their findings, published this week in the journal Scientific Reports, suggest several of the newly developed miRNAs are related to the domestication process.
Researchers found an especially large concentration of new miRNA molecules in tissue samples collected from canine testicles. Some of these new miRNAs could explain the diversity in behavior and appearance among dog breeds produced by the domestication process.
Understanding the influence of domestication on genetic evolution can help researchers improve care practices for animals, enhance domestic crop varieties and even better understand the development of human diseases.
"Understanding the roles of miRNAs and their co-evolution with target genes in domestication can help not only improve understanding of fundamental biological processes but will also help us to better understand key traits of domestication selection with important applications to food security," Federica Di Palma, director of science at Earlham.