Spontaneous single nucleotide polymorphism in porcine microRNA-378 seed region leads to functional alteration.

Sequence variation in a microRNA (miRNA) seed region can influence its biogenesis and effects on target mRNAs; however, in mammals, few seed region mutations leading to functional alterations have been reported to date. Here, we report the identification of a single nucleotide polymorphism (SNP) with functional consequence located in the seed region of porcine miR-378. In vitro analysis of this rs331295049 A17G SNP showed significantly up-regulated expression of the mature miR-378 (miR-378/G). In silico target prediction indicated that the SNP would modulate secondary structure and result in functional loss affecting >85% of the known target genes of the wild-type miR-378 (miR-378/A), and functional gain affecting >700 new target genes, and dual-luciferase reporter assay verified this result. This report of a SNP in the seed region of miR-378 leads to functional alteration and indicates the potential for substantive functional consequences to the molecular physiology of a mammalian organism.

Epigenetics regulates gene expression patterns of skeletal muscle induced by physical exercise.

As it is well known, proper exercise benefits our mind and body, especially the skeletal muscle. Exercise increases the capacity of muscle metabolism, enhances the biological function of mitochondria, regulates the transformation of muscle fiber types and increases the muscle power. In recent years, more and more researches show that epigenetic regulation plays an important role in strengthening the muscle, and these studies mainly include DNA methylation, histone modification, and regulation of miRNA expression. In order to adapt to the body movement, these three epigenetic patterns change the metabolic capacity of skeletal muscle, mitochondrial biological function and muscle fiber types by regulating the gene expression of skeletal muscle. In this review, we summarize research progresses of exercise-induced epigenetic regulation of gene expression of skeletal muscle, in order to provide a reference for further studies of how sports improve our body health.

The current research status of enhancer RNAs.

Enhancers are key cis-acting gene regulatory elements in eukaryotes, which can effectively promote the expression of target genes. Emerging evidence showed that enhancers in activation state could be transcribed to enhancer RNAs (eRNAs), the processes of which are regulated by various signaling systems and actions of signal-dependent transcription factors. Compared with the other transcripts (e.g. lncRNA, mRNA), eRNAs have shorter sequences, lower stability, and higher tissue specificity. eRNAs play roles in the initiation or stabilization of enhancer-promoter looping, and promote the expression of target genes. Recent studies have further showed that eRNAs have crucial roles in biological processes, such as development and disease initiation and progression. However, functional studies of eRNAs are currently lacking, and the regulatory mechanisms of eRNAs are still uncertain. Herein, we focus on the features, research methods and functional properties of eRNAs, and discusse the possibility of using eRNAs as therapeutic targets. We hope this discussion might provide some insights for further research on eRNAs.