Novel and conserved MiRNAs identification from Citrus sinensis by solexa sequencing

【Objective】Finding out the Citrus sinensis miRNAs and predicting their mechanism of action and function will provide a lot of information for developing new varieties of C.sinensis with disease resistance and studying further plant-pathogen interaction.The interaction mechanism between C.sinensis and pathogens will lay a solid foundation for the further study of the miRNA.【Method】Small RNA sequences library was obtained by high-throughout sequencing technology.With respect to C.sinensis reference genome,miRNA identification and prediction of miRNAs target genes were carried out by bioinformatics software and databases.The target genes of miRNA were classified by search against the GO and the KEGG databases.【Results】12617944 small RNA sequences were acquired accounting for 99.32% of the total sequences and 3065625 were unique sequences.The 24 nt length small RNA is the major RNAs in the total sequences,accounting for 49.03% of the total sequences.A total of 2199561 miRNA sequences were obtained including 638722 conserved and 21030839 novel miRNA sequences.1777 target genes of unique novel miRNAs and 927 target genes of 52 unique conserved miRNAs were found.Based on Gene Ontology database,the target unigenes may be involved in the multicellular organismal process and the nucleic acid binding transcription factor activity molecular function.The target genes of miRNA are associated with transcription factors,disease resistance proteins and receptor kinase on the mapping of plantpathogen intraction map in KEGG database,etc.【Conclusion】A number of C.sinensis miRNAs and their target genes were found in this study.The results will facilitate the further study.