Discovery and Profiling of Chinese Qinchuan Bovine microRNAs Involved in Regulating Muscle Proliferation and Differentiation

Background: MicroRNAs (miRNAs) are a family of ~22 nucleotide small RNA molecules which regulate gene expression by fully or partially binding to their complementary sequences. Recently, a large number of miRNAs and their expression patterns have been identified in various species. However, no miRNA to date has been reported to modulate muscle development in beef cattle. Results: we constructed two small RNA libraries for Solexa SBS technology sequencing, and a total of 15,454,182 clean reads were obtained from the fetal bovine library and 13,558,164 clean reads from the adult bovine library. In total, 521 miRNAs including 104 novel miRNA candidates were identified. Furthermore, the nucleotide bias, base edit and family of the known miRNAs were also analyzed. Based on stem-loop qPCR, 25 high-read miRNAs were detected, and the results showed that bta-miRNA-543, miRNA-206, miRNA-1, miRNA-133, miRNA-432, miRNAn12, miRNAn17 and miRNAn73 were  highly expressed in muscle-related tissue or organs, suggesting that these miRNAs may play a role in the development of bovine muscle tissues. Conclusions: This study led to the confirmation of the authenticity of 417 known miRNAs and the discovery of 104 novel miRNAs in Bos taurus, and 8 muscle-specific miRNAs were identified. The identification of novel miRNAs expanded significantly the repertoire of bovine miRNAs and could be contributive to various and further studies on muscle development of cattle.

Key words: bovine, deep sequencing technology, microRNA, muscle, proliferation and differentiation

Corresponding author:

Prof. Dr. Hong Chen, College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Molecular Biology for Agriculture, Yangling, Shaanxi 712100, China.

E-mail:  chenhong1212@263.net