Comprehensive circular RNA expression profiles in intermuscular fat from lean and obese pigs

Abstract

Circular RNA (circRNA) plays an important regulatory role in development and differentiation. Intermuscular fat in pork affects the tenderness and juiciness of the meat. In this study, we investigated the performances of Landrace (lean) and Jinhua (obese) pigs at the fattening period and explored the expression profile of circRNAs in intermuscular fat from the two breeds by Illumina high-throughput sequencing. we identified 5 548 circRNAs, specifically 2 651 (47.78%) in the Jinhua pigs, and 2 897 (52.22%) in the Landrace pigs. A totale of 809 differentially expressed circRNAs were observed between the the Jinhua and Landrace pigs, but only 29 of these circRNAs showed significant difference (19 upregulated and 10 downregulated). All 1 306 unigenes and 27 differentially expressed unigenesinvolved in lipid transport and metabolism; replication, recombination and repair; and signaling pathway were annotated. A total of 550 target miRNAs were perfect seed matches and 20 522 target genes were foundBy RNAhybrid and miRanda software prediction. Results from real-time quantitative PCR also confirmed the differential expression of 13 mRNAs between the two pig breeds. This study provides comprehensive expression profiles of circRNAs in Sus scrofa adipose metabolism and development, which can be used to clarify their functions. Summary statementThe paper explored the expression profile of circRNAs in intermuscular fat from Landrace and Jinhua pigs at the fattening period, to provide insights into circRNAregulation in animal adipose metabolism.