Transcriptome reveals key microRNAs involved in fat deposition between different tail sheep breeds.

Xiaojuan Fei,Zengkui Lu,Zehu Yuan,Taotao Li,Huihua Wang,Caihong Wei,Meilin Jin,Jian Lu,Kai Quan,Yuqin Wang,Ran Di,Abdul Qadir Syed

doi:10.1371/journal.pone.0264804

Abstract

MicroRNA (miRNA) is a kind of noncoding RNA whose function involved in various biological processes in neuronal maturation and adipocyte cells, such as differentiation, proliferation, development, apoptosis, and metabolism. Herein, miRNA-Seq was used to identify miRNAs in the tail fat tissue of Hu sheep (short-fat-tailed) and Tibetan sheep (short-thin-tailed). In this study, 155 differentially expression miRNAs (DE miRNAs) were identified, including 78 up-regulated and 77 down-regulated. Among these DE miRNAs, 17 miRNAs were reported and related with lipid metabolism. MiRanda and RNAhybrid software were used to predict the target genes of DE miRNAs, obtaining the number of targeting relationships is 38553. Target genes were enriched by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). 742 terms and 302 single pathways are enriched, including lipid metabolic process, response to lipid, cellular lipid catabolic process, lipid catabolic process, cellular lipid metabolic process, inositol lipid-mediated signaling, calcium channel activity, PI3K-Akt signaling pathway, MAPK signaling pathway, ECM-receptor interaction, AMPK signaling pathway, Wnt signaling pathway and TGF-beta signaling pathway. Notably, miR-379-5p was associated with tail fat deposition of sheep. Dual-Luciferase reporter assays showed miR-379-5p and HOXC9 had targeted relationship. The result of RT-qPCR showed that the expression trend of miR-379-5p and HOXC9 was opposite. miR-379-5p was down-regulated and highly expressed in tail adipose tissue of Tibetan sheep. HOXC9 was highly expressed in adipose tissue of Hu sheep. These results could provide a meaningful theoretical basis for studying the molecular mechanisms of sheep tail adipogenesis.

Highlights

This study identified some miRNAs that may play an important role in fat metabolism
MiR-495-3p [22] was differentially expressed between fasting and postprandial states, and the target genes of DE miRNA were annotated in MAPK signal pathway and PI3K-Akt signaling pathway
The result of RT-qPCR showed that the expression trend of miR-379-5p and HOXC9 was opposite. miR-379-5p was highly expressed in tail adipose tissue of Tibetan sheep

Summary

Methods

Ethical approval was given by the Animal Committee of the IAS-CAAS (No IAS 2020–82). Samples of ovine tail fat were collected from three Hu sheep (short-fat-tailed sheep, Yongdeng, Gansu, China) and three Tibetan sheep (short-thin-tailed sheep, Yushu, Qinghai). Collecting tail fat tissue of each sheep, immediately frozen in liquid nitrogen in RNase-free 1.5 mL freezing tubes, and store at -80 ̊C for use. Total RNA was extracted by TRIzol (Invitrogen, CA, USA) following the manufacturer’s instruction. Using NanoDrop2000 spectrophotometer to quantify RNA purity at 260 and 280 nm (Thermo Fisher Scientific, MA, USA). Integrity of RNA and library was examined by Agilent 2100 Bioanalyzer (Agilent Technologies, CA, USA). Six libraries were constructed, named HZ1, HZ2, HZ3, ZZ1, ZZ2 and ZZ3.

Results

Discussion

Conclusion