Discovery and functional study of lncRNAs associated with fat deposition in Kele pigs based on whole-transcriptome RNA sequencing.

Objective: To screen out the lncRNAs related to fat deposition in Kele pigs and explore their molecular regulatory mechanisms through biological function verification, it is expected to provide a theoretical basis for breeding, development and utilization of Kele pigs.

Methods: In this work, 6 healthy 10-month-old Kele pigs were selected as the experimental subjects and divided into high and low backfat thickness groups. Subcutaneous adipose tissue of each group was collected for whole-transcriptome RNA sequencing (RNA-seq) and lncRNAs associated with backfat thickness were randomly selected for real-time quantitative PCR (RT-qPCR) analysis. The correlation analysis between lncRNAs expression and production data was conducted, and the biological function of lncRNAs were identified.

Results: A total of 493 lncRNAs with significantly different expression were found by RNA-seq (p<0.05), and it was found that TCONS_00185937 and TCONS_00161198 may be involved in the regulation of fat deposition. The results of RT-qPCR were consistent with RNA-seq, indicating that the sequencing results were reliable. Correlation analysis showed that the expression of TCONS_00185937 was significantly negatively correlated with backfat thickness, and the expression of TCONS_00161198 was significantly positively correlated with backfat thickness, and negatively correlated with eye muscle area (p<0.05). The pEGFP-TCONS_00185937 was transfected into subcutaneous fat precursor cells, it was found that the expression levels of TCONS_00185937 and its target genes MOGAT2 and ATGL were significantly higher than control group (p<0.05). Similarly, pEGFP-TCONS_00161198 transfected cells found that the expression levels of TCONS_00161198 and its target genes CSF3R and ACC were significantly higher than control group (p<0.05). The induced differentiation of transfected cells found that the OD510 absorption value of pEGFP-TCONS_00161198 group was higher than that of the control group. Triglyceride content was significantly higher than that of control group (p<0.01), while OD510 absorption value and triglyceride content of pEGFP-TCONS_00185937 group were lower than that of control group.