High-throughput sequencing discovery of conserved and novel microRNAs in Chinese cabbage (Brassica rapa L. ssp. pekinensis).
MicroRNAs (miRNAs) are a class of 21-24 nucleotide non-coding RNAs that down-regulate gene expression by cleaving or inhibiting the translation of target gene transcripts. miRNAs have been extensively analyzed in a few model plant species such as Arabidopsis, rice and Populus, and partially investigated in other non-model plant species. However, only a few conserved miRNAs have been identified in Chinese cabbage, a common and economically important crop in Asia. To identify novel and conserved miRNAs in Chinese cabbage (Brassica rapa L. ssp. pekinensis) we constructed a small RNA library. Using high-throughput Solexa sequencing to identify microRNAs we found 11,210 unique sequences belonging to 321 conserved miRNA families and 228 novel miRNAs. We ran a Blast search with these sequences against the Chinese cabbage mRNA database and found 2,308 and 736 potential target genes for 221 conserved and 125 novel miRNAs, respectively. The BlastX search against the Arabidopsis genome and GO analysis suggested most of the targets were involved in plant growth, metabolism, development and stress response. This study provides the first large scale-cloning and characterization of Chinese cabbage miRNAs and their potential targets. These miRNAs add to the growing database of new miRNAs, prompt further study on Chinese cabbage miRNA regulation mechanisms, and help toward a greater understanding of the important roles of miRNAs in Chinese cabbage.
Institute of Vegetables, Shandong Academy of Agricultural Sciences Shandong, Key Laboratory of Greenhouse Vegetable Biology, Shandong Branch of National Vegetable Improvement Center, Jinan 250100, China.
Fengde
F
Wang
Libin
L
Li
Lifeng
L
Liu
Huayin
H
Li
Yihui
Y
Zhang
Yingyin
Y
Yao
Zhongfu
Z
Ni
Jianwei
J
Gao
D001483:Base Sequence; D029741:Brassica rapa / Q000235:genetics*; D017124:Conserved Sequence / Q000235:genetics; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D015723:Gene Library; D059014:High-Throughput Nucleotide Sequencing / Q000379:methods*; D035683:MicroRNAs / Q000235:genetics*; D008969:Molecular Sequence Data; D018749:RNA, Plant / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA / Q000379:methods
D018076:DNA, Complementary; D035683:MicroRNAs; D018749:RNA, Plant