关键词: 梨, 休眠芽, miRNA, 高通量测序, 生物信息学, qPCR

Abstract: In order to explore the expression pattern and target genes of microRNAs associated with dormancy of pear flower buds，we used Solexa sequencing，bioinformatics analysis and qPCR to screen and identify the small RNAs of pear flower buds at stages of endodormancy，endodormancy release and ecodormancy release. The results showed that there were 12 276 226，10 135 952 and 11 453 981 unique reads in endodormancy，endodormancy release and ecodormancy release libraries，respectively. The size distribution of small RNAs mainly ranged from 21–24 nt，with 24 nt small RNAs being the most abundant. A total of 151 known miRNAs were identified from three samples，which belong to 39 different families，and 209 novel miRNAs were predicted using bioinformatics software. Through comparative expression profiling of the miRNAs during the transition period from endodormancy to ecodormancy release，we found 8 differentially expressed miRNAs（ahy-miR156b-5p，cpa-miR319，aly-miR172c-3p，aau-miR396，mdm-miR858，aly-miR171b-3p，bdi-miR160f and hbr-miR166a）. The predicted target genes of the 8 miRNAs were mainly involved in transcription regulation，signal transduction and so on. Finally，we confirmed the differential expression of the 8 miRNAs and 8 target genes by qPCR.

Key words: pear, flower bud dormancy, microRNA, high throughput sequencing, bioinformatics, qPCR