Expression Profile Analysis Of Long Noncoding RNA And MRNA In The Blood Of Pigs During Postnatal Development

Blood is the pipeline of the immune system.Assessing changes in transcript abundance in blood on a genome-wide scale affords a comprehensive view of the status of the immune system in health and disease.In this study,we performed high-throughput sequencing to survey the long non-coding RNA(lnc RNA)and m RNA transcriptome using pig peripheral blood samples at five developmental time points(0,7,28,180 days,and 2years of age),which represent five important pig developmental stages(newborn,suckling,weaning,sexual maturity,and adulthood).We adopted a series of bioinformatics methods to study functional transcriptome and regulatory transcriptome of blood.The main results are described as follows:(1).A total of 12,354 m RNA and 5,946 lnc RNA transcripts were identified among the10 samples from pigs.Compared with m RNA,the length of lnc RNA was much shorter,exon number of lnc RNA was fewer,and the open reading frame of lnc RNA was much lower at expression level.(2).The five stages were divided into two classes: the suckling period(0,7 and 28days)and the late stage of development(180 days and 2 years).(3).The m RNAs expressed at all five time points were mainly involved in categories related to cellular component,immune response,genetic information processing,process of metabolism,and diseases.The lnc RNAs expressed at all five time points were mainly associated with the regulation of cellular component,immune response,oxidative phosphorylation,and poly(A)RNA binding.(4).Short time-series expression miner(STEM)showed that most m RNAs were expressed at a low level in the suckling period(0,7 and 28 days),but at a higher level in the late stage of development(180 days and 2 years).The functions of the m RNAs with the greatest variation of expression levels between the two developmental periods were mainly associated with the regulation of transcription,intestinal immune network for Ig A production,osteoclast differentiation and NF-kappa B signaling pathway.Most lnc RNAs and m RNAs had similar temporal expression patterns during development,indicating the expression correlation and functional relatedness between them.(5).A number of T-cell-related genes expression continuously increased in the suckling period,indicating that these genes are crucial for the establishment of the adaptive immune system of piglets at this stage.(6).A total of 980 differentially expressed lnc RNAs in the three comparison groups(D0 vs.D7,D7 vs.D28,and D180 vs.Y2).All above,this study provides a catalog of pig peripheral blood-related lnc RNAs and m RNAs,and reveals the characteristics and temporal expression profiles of lnc RNAs and m RNAs during peripheral blood development through the newborn stage to adult life in pigs.