Bos taurus and Bison bison Conservative Retrotransposon Recombination Products

Galina Glazko ^1* Gleb Yu. Kosovsky ² Olga I. Skobel ²

• ¹ BoiMecial Informatics, University of Arkansas for Medical Sciences, Little Rock, United States
• ² Afanas`ev Research Institute of Fur-Bearing Animal Breeding and Rabbit Breeding,, Moscow Province, Russia

Background: Without identifying and studying genomic characteristics associated with domestication, managing farm animal genetic resources is overwhelmingly difficult. Accumulated data confirm that mobile genetic elements participate in domestication processes and, in particularly, they generate widely abundant microRNAs. Methods: The recombination products between the long interspersed nuclear element and endogenous retrovirus LINE/ERV/LINE, located in a closely linked conserved block of 12 genes, and microRNAs formed by these recombination products in domesticated-wild pair of mammals were compared in silico. For this comparison, the reference genomes of domesticated cattle (Bos taurus) and its closely related wild species counterpart, bison (Bison bison) were used. Results: It was found that the above-noted highly conserved recombination products (more than 81.5% identity) were present in the corresponding block of 12 genes in bison. They are sources of 51 microRNAs in bison and 129 microRNAs in cattle, including 50 microRNAs, similar for both species. 79 microRNAs were found only in cattle trinomial recombination products and 98% of them were from the mir-30 family, including cattle-specific bta-miR-30a-5p and bta-miR-30e-5p. The mir-30 family is closely associated with biological processes influencing the quantity and quality of agricultural products. Conclusion: Trinomial retrotransposon recombination products were fixed both in the cattle genome and in the genome of its closely related wild species, the bison. It was found that these products could be involved in the response to intensive artificial selection and domestication process since interspecific differentiation of microRNAs is associated with regulatory networks that have a significant impact on economically important trait formation.