Identification And Profiling Of MicroRNAs From Skeletal Muscle Of The Common Carp

The common carp occupies a prominent position in the world of freshwater aquaculture and serves as a major source of animal protein for millions of people. In spite of its aquacultural importance and a production increase in carp breeding over the last decade, their developmental mechanisms remain unknown. The muscle is one of the most important tissues in the vertebrate, and it distributes on the surface of tissues or skeleton. The skeletal muscle, is called striated muscle, is composed of contractive myocyte. The skeletal muscle can offer vertebrate the ability of movemont. And the comestible partion of common carp is also mainly derived from the skeletal muscle.It has been shown that a class of non-coding about22nucleotide RNAs named microRNAs (miRNAs) play important roles in vertebrate development. They regulate gene expression through sequence-specific interactions with the3’untranslated regions (UTRs) of target mRNAs and thereby cause translational repression or mRNA destabilization. Although the function and mechanism of miRNAs in mouse, rat, human and other model animals have been clearly known, the role of miRNAs in the skeletal muscle development of the common carp remains unknown.In this study, a small-RNA cDNA library was constructed from the skeletal muscle of the common carp. Meanwhile, Solexa sequencing technology was used to perform high throughput sequencing of the libraries.188conserved miRNAs and7novel miRNAs in the carp skeletal muscle were identified by subsequent bioinformatics analysis.For validation and further identification of muscle-related miRNAs in the common carp, the analysis of miRNA expression was performed in different tissues of the common carp. Then, to further explore the miRNAs involved in the skeletal muscle development of the common carp, we performed quantitative analysis of the miRNAs in skeletal muscle tissues of30day posthatching (dph) larva,1-year-old common carps, and2-year-old common carps. Meanwhile, the expression of miRNAs was also analyzed from germcell to adult fish in different developmental stages.The results show that miR-1, miR-133a-3p, and miR-206were specifically expressed in muscle-containing organs, and miR-1, miR-21, miR-26a, miR-27a, miR-133a-3p, miR-206, miR-214and miR-222were differentially expressed in the process of skeletal muscle development of the common carp.This study provides a first identification and profiling of miRNAs related to the muscle biology in the common carp. The miRNA identification could provide a better understanding of the molecular mechanisms for carp skeletal muscle development. The common carp as a representitive of teleost fishs is studied that contribute to impove fish breed and production.