Bovine bta-microRNA-1271 Promotes Preadipocyte Differentiation by Targeting Activation Transcription Factor 3

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H. Y. Xu^1#, J. Shao^1#, B. Z. Yin¹, L. M. Zhang¹, J. C. Fang², J. S. Zhang¹, and G. J. Xia^1,a*

¹Agriculture College, Yanbian University, 133002 Yanji, Jilin, China

²Faculty of Agriculture and Life Science, Hirosaki University, 036-8560 Hirosaki, Japan

^# These authors contributed equally to this work.

^* To whom correspondence should be addressed.

Received March 4, 2020; Revised May 21, 2020; Accepted May 21, 2020

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Yanbian yellow cattle are one of the top five largest breeds of cattle in China. We had previously found that bta-miR-1271 is differentially expressed in the longissimus dorsi muscles of Yanbian yellow bulls and steers. However, whether bta-miR-1271 affects bovine fat formation is unclear. In this study, we used target gene prediction, dual-luciferase reporter assay, and transfection-mediated overexpression and inhibition of bta-miR-1271 in a culture of Yanbian yellow cattle preadipocytes to investigate the role of bta-miR-1271 in adipogenesis. We showed that bta-miR-1271 directly targets the 3′-untranslated region (3′-UTR) of the activating transcription factor 3 (ATF3) mRNA and downregulates its expression. Overexpression of bta-miR-1271 enforced by the miRNA mimics promoted triglyceride accumulation and significantly upregulated expression of the adipogenic peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT enhancer-binding protein α (C/EBPα) genes at both the protein and mRNA levels, as demonstrated by RT-qPCR and Western blot analyses. Conversely, inhibition of bta-miR-1271 expression produced the opposite effect. Our results show that bta-miR-1271 regulates differentiation of Yanbian yellow cattle preadipocytes by inhibiting ATF3 expression, which highlights the importance of microRNA-mediated regulation of adipogenesis. miR-1271 and its target gene(s) may provide a new research direction for investigating biological agents affecting intramuscular fat deposition in cattle.

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KEY WORDS: ATF3, bta-miR-1271, preadipocyte differentiation, Yanbian yellow cattle

DOI: 10.1134/S0006297920070032

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