Comparative analysis of miRNA expression in Oryza sativa cultivar PTB33 and TN1

Abstract

It has been known that microRNAs (miRNAs) are involved in the regulation for the plant development and defense mechanism by regulating the expression of the target gene. In this study, by adopting next-generation sequencing, we profiled the miRNA expression profile from two rice cultivars, one susceptible (TN1) and another resistant to the brown planthopper (PTB33). Two small RNA libraries from Oryza sativa TN1 and PTB33 were constructed and sequenced. Bioinformatic analyses revealed that 66 unique osa-miRNAs were found to be differentially-expressed in PTB33 library, including 41 up-regulated and 25 down-regulated miRNAs. These differentially expressed osa-miRNAs have been reported to be involved in a variety of cellular processed in rice, especially immune response. By using stem-loop qRT-PCR, the expression of the representative miRNAs, including osa-miR393, osa-miR398 and osa-miR7695 was found to be up-regulated, corresponding to the sequencing data. Hence, the PTB33 cultivar-specific miRNAs, which might be involved in BPH disease resistance have been identified. This might be useful for biotechnological approaches for crop protection and development.

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