Abstract
BackgroundMicroRNAs (miRNAs) are a class of endogenous small non-coding RNAs of 20–25 nucleotides that play a key role in diverse biological processes. Japanese flounder undergo dramatic metamorphosis in their early development. The metamorphosis is characterized by morphological transformation from a bilaterally symmetrical to an asymmetrical body shape concomitant with extensive morphological and physiological remodeling of organs. So far, only a few miRNAs have been identified in fish and there are very few reports about the Japanese flounder miRNA.Methodology/Principal FindingsSolexa sequencing technology was used to perform high throughput sequencing of the small RNA library from the metamorphic period of Japanese flounder. Subsequently, aligning these sequencing data with metazoan known miRNAs, we characterized 140 conserved miRNAs and 57 miRNA: miRNA* pairs from the small RNA library. Among these 57 miRNA: miRNA* pairs, twenty flounder miRNA precursors were amplified from genomic DNA. We also demonstrated evolutionary conservation of Japanese flounder miRNAs and miRNA* in the animal evolution process. Using miRNA microarrays, we identified 66 differentially expressed miRNAs at two metamorphic stages (17 and 29 days post hatching) of Japanese flounder. The results show that miRNAs might play a key role in regulating gene expression during Japanese flounder metamorphosis.Conclusions/SignificanceWe identified a large number of miRNAs during flounder metamorphosis, some of which are differentially expressed at two different metamorphic stages. The study provides an opportunity for further understanding of miRNA function in the regulation of flounder metamorphosis and gives us clues for further studies of the mechanisms of metamorphosis in Japanese flounder.
Highlights
MicroRNAs are endogenous,22 nucleotides, small non-coding RNA molecules that regulate gene expression by complementary binding to the 39 untranslated region (UTR) of target messenger RNAs and causing mRNA cleavage or translation blockage [1]
Solexa sequencing of small RNAs To identify flounder miRNAs during metamorphosis, a small cDNA library that was generated from a mixture of total RNAs from nine metamorphic stages was subjected to high-throughput sequencing by the Illumina platform
Using a high-throughput Solexa sequencing approach, we identified 140 conserved miRNAs and 57 miRNA*s and analysed expression profiles of these miRNAs during metamorphosis of Japanese flounder, a species without a completely sequenced genome
Summary
MicroRNAs (miRNAs) are endogenous, ,22 nucleotides (nt), small non-coding RNA molecules that regulate gene expression by complementary binding to the 39 untranslated region (UTR) of target messenger RNAs (mRNAs) and causing mRNA cleavage or translation blockage [1]. MiRNAs play a key role in diverse biological processes such as organ development, cell proliferation, tumorigenesis, fat metabolism, behavior and embryogenesis [1,2,3,4,5,6]. The first characterized endogenous miRNAs were lin-4 and let-7, both of which were found to act in the pathway controlling the timing of larval development in C. elegans [12,13]. MicroRNAs (miRNAs) are a class of endogenous small non-coding RNAs of 20–25 nucleotides that play a key role in diverse biological processes. Japanese flounder undergo dramatic metamorphosis in their early development. Only a few miRNAs have been identified in fish and there are very few reports about the Japanese flounder miRNA
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
