Gene expression profile of circRNA in spleen tissue of Meishan pigs at different time points
Numerous circular RNAs (circRNAs) have been recently identified in porcine tissues and cell types. Nevertheless, their significance in porcine spleen development is yet unelucidated. Herein, we report an extensive overlook of circRNA expression profile during Meishan pig spleen development at 1, 7, 14, 21, 28, 35, 120, and 180 days of age. Overall, 39,641 circRNAs were identified from 6,914 host genes. Among them, many circRNAs are up- or down-regulated at different time points of pig spleen development. Using WGCNA analysis, we revealed two essential modules for protein-coding genes and circRNAs. Subsequent correlation analysis revealed 67 circRNAs/co-expressed genes that participated in immnue-associated networks. Furthermore, a competing endogenous RNA (ceRNA) network analysis of circRNAs revealed that 12 circRNAs modulated CD226, MBD2, SAMD3, SIT1, SRP14, SYTL3 gene expressions via acting as miRNA sponges. Moreover, the circRNA_21767/miR-202-3p axis regulated SIT1 expression in a ceRNA manner, which is critical for the immune-based regulation of spleen development in Meishan pigs. Overall design: Spleen tissue of Meishan pig at different time points