Identification and functional prediction of long intergenic noncoding RNAs in fetal porcine longissimus dorsi muscle

Pigs are globally farmed animals which provide protein for human consumption in the form of skeletal muscle. To better understand the function of long intergenic noncoding RNAs (lincRNAs) in porcine skeletal muscle growth and development, we collected RNA-seq data from porcine longissimus dorsi muscle (LDM) during embryonic development. We identified a total of 739 lincRNA transcripts, which were distributed on all chromosomes except the chromosome Y, and analyzed their molecular characteristics. Compared to protein-coding genes, lincRNAs showed shorter transcripts, longer exons, fewer exons and higher tissue specificity. In addition, the abundance of lincRNAs in five embryonic development stages were analyzed and 45 differentially expressed lincRNAs were screened, three of which were highly expressed in LDM during porcine embryonic development. Finally, we predicted the potential target genes and functions of the lincRNAs, and identified 1 537 cis-target genes and 8 571 trans-target genes. Furthermore, we identified two key candidate lincRNAs involved in muscle development, XLOC_024652 and XLOC_001832, for post-trial validation. Our results provide a genome-wide resource of lincRNAs which are potentially involved in porcine embryonic skeletal muscle development and lay a foundation for the further study of their functions.