Isolation and identification of novel microRNAs from Marsupenaeus japonicus.

MicroRNAs (miRNAs) are a class of small noncoding RNAs that function as regulators of gene expression. They play essential roles in various biological processes, such as development, differentiation and immune response. In this study, we identified 35 miRNAs from Marsupenaeus japonicus. Among them, fifteen miRNAs exhibited high homology to the known miRNAs from other arthropods, while the rest might represent novel miRNAs. We further showed a correlation of WSSV infection and the expression levels of 22 miRNAs. This is the first report to identify miRNAs from the shrimp. Our results extend the knowledge of the gene regulation of crustacean, providing clues for future researches of shrimp immunity against virus infection.