Mapping of six miRNAs expressed in porcine skeletal muscle

Microarray-based approach identifies differentially expressed microRNAs in porcine sexually immature and mature testes

Background

MicroRNAs (miRNAs) are short non-coding RNA molecules which are proved to be involved in mammalian spermatogenesis. Their expression and function in the porcine germ cells are not fully understood.

Methodology

We employed a miRNA microarray containing 1260 unique miRNA probes to evaluate the miRNA expression patterns between sexually immature (60-day) and mature (180-day) pig testes. One hundred and twenty nine miRNAs representing 164 reporter miRNAs were expressed differently (p<0.1). Fifty one miRNAs were significantly up-regulated and 78 miRNAs were down-regulated in mature testes. Nine of these differentially expressed miRNAs were validated using quantitative RT-PCR assay. Totally 15919 putative miRNA-target sites were detected by using RNA22 method to align 445 NCBI pig cDNA sequences with these 129 differentially expressed miRNAs, and seven putative target genes involved in spermatogenesis including DAZL, RNF4 gene were simply confirmed by quantitative RT-PCR.

Conclusions

Overall, the results of this study indicated specific miRNAs expression in porcine testes and suggested that miRNAs had a role in regulating spermatogenesis.

MicroRNA: mechanism of gene regulation and application to livestock

Posttranscriptional regulation of gene expression plays a role in multiple cellular pathways. MicroRNA (miRNA) are an emerging class of small RNA that regulate gene translation. However, the mechanisms by which miRNA regulate this process remain controversial. By altering posttranscriptional regulation, miRNA have a role in guiding developmental decisions, including cell fate, cell cycle progression, apoptosis, adipocyte differentiation, and processes that alter muscle development and growth. The role of miRNA in developmental decisions that affect animal biology is of significant interest, yet the current literature is limited in livestock models. Therefore, a review of the mechanisms by which miRNA alter gene translation and the current research evaluating miRNA in production livestock is needed.