Identification of mRNA and Long Non-Coding RNA Expression Profiles in Developing Yorkshire Pig Spleens

Abstract

Background: Epidemic diseases cause great economic loss in pig farms each year, some of which are characterized mainly in spleen. Yorkshire pig is the most popular used first dam in the commercial pork production system. But the mRNA and lncRNA expression networks in developing Yorkshire pig spleens remain obscure. Results: Here, we profiled the systematic characters of mRNA and lncRNA repertoires in three groups of spleens from nine Yorkshire pigs, each three aged at 7 days, 90 days and 180 days. By using a precise mRNA and lncRNA identification pipeline, we identified 19,647 genes and 219 known and 3,219 putative lncRNA transcripts, 1,729 genes and 64 lncRNAs therein were found to express differentially in three groups. Gene expression characteristics of genes and lncRNAs were found to be basically fixed before 90 days after birth. Enrichment analysis of differentially expressed genes and potential target genes of differentially expressed lncRNAs both displayed crucial roles of up-regulation in immune activation and hematopoiesis and down-regulation in cell replication and division in 90 and 180 days compared to 7 days. The unregulated terms and their significance levels in 90 and 180 days both showed an extremely high degree of consistency. ENSSSCT00000001325 was the only lncRNA transcript that existed in three groups. CDK1, PCNA and PLK were detected to be hub genes that varied with age. BNIP3L, IL5, CD38 and TGFβ1 were found to be common top regulators from 7 to 90 and 180 days while ERAP1, NLRC5 and IL2RG were top regulators from 90 to 180 days.Conclusions: This study provided the first mRNA and lncRNA expression profiles in Yorkshire spleens at three developmental stages. We established gene expression modules and networks in the spleen of pigs from immune system initiation to adulthood. Our results are helpful for the study of transcriptome and functional genomics of spleen tissue in farm animals.