Project description:Long non-coding RNAs (lncRNAs) play important roles in diverse biological processes. However, the landscape of lncRNAs is largely unclear in Sus scrofa. Here we performed stranded RNA-seq on total RNA libraries from over 100 samples of Sus scrofa tissues. We identified 10,813 lncRNAs in Sus scrofa, of which 9,075 are novel. 57% of these lncRNAs were conserved in both human and mouse. These conserved lncRNAs tend to be more tissue-specific than pig-specific lncRNAs, and enriched in reproducible organs (i.e. testis and ovary). We characterized a group of lncRNAs potentially involved in the skeletal muscle development. One such lncRNA, a homolog of maternally expressed gene 3 (MEG3), was specifically expressed in the skeletal muscle at early developmental stage. And its expression pattern is conserved in pig and mouse. By over-expressing and knocking down MEG3 in mouse myoblast cell lines, we demonstrated its novel function as a myoblast proliferation suppressor.
Project description:The pig could be a useful model to characterize molecular aspects determining several delicate phenotypes because they have been bred for those characteristics. The Korean native pig (KNP) is a regional breed in Korea that was characterized by relatively high intramuscular fat content and reddish meat color compared to other western breeds such as Yorkshire (YS). YS grew faster and contained more lean muscle than KNP. We compared the KNP to Yorksire to find molecular clues determining muscle characteristics. The comparison of skeletal gene expression profiles between these two breeds showed molecular differences in muscle. We found 82 differentially expressed genes (DEGs) defined by fold change (more than 1.5 fold difference) and statistical significance (within 5% of false discovery rate). Functional analyses of these DEGs indicated up-regulation of most genes involved in cell cycle arrest, down-regulation of most genes involved in cellular differentiation and its inhibition, down-regulation of most genes encoding component of muscular-structural system, and up-regulation of most genes involved in diverse metabolism in KNP. Especially, DEGs in above-mentioned categories included a large number of genes encoding proteins directly or indirectly involved in p53 pathway. Our results indicated a possible role of p53 to determine muscle characteristics between these two breeds. Experiment Overall Design: Comparing gene expression profiles to discover differentially expressed genes from skeletal muscles of two different pig breeds.
Project description:We sequenced the whole mRNA of six pig (Sus scrofa) fat, liver and muscle tissues, generating a total of 1.3 billion short reads with 90-bp pair-end sequences from 24 samples. Comparing with current genome annotation, we identified 32,361 unigene clusters spanning 51.83 Mb that contained 11,933 (36.87%) annotated genes. More than 60% (20,428) unigene clusters did not match any current equine gene model. We identified 189,973 single nucleotide variations (SNVs) from the aligned sequences against the horse reference. Most SNVs (171,558 SNVs; 90.31%) were novel compared with over 1.1 million equine SNPs from two databases. Some genes have significantly different expression levels under different environment. We define those identical genes which have different expression levels are ‘differentially expressed’ and carried out differentially expressed gene analysis before and after exercise conditions. We discovered, 62 up- and 80 down-regulated genes in the blood and 878 up- and 285 down-regulated genes in the muscle from the 24 samples. Six out of 28 previously exercise-related known genes, HIF1A, ADRB2, PPARD, VEGF, TNC, and BDNF, were highly expressed in the muscle after exercise. We discovered 56 functionally unknown transcription factors that are probably associated with an early regulatory exercise mechanism from 91 differentially expressed transcription factors. We found interesting RNA expression patterns where different alternative splicing forms of the same gene showed reversed expressions before and after exercising. whole mRNA sequencing profiles of six pig (Sus scrofa) fat, liver and muscle tissues