title: Identification and characterization of microRNAs from peanut (Arachis hypogaea L.) by high-throughput sequencing.
abstract: BACKGROUND
  MicroRNAs (miRNAs) are noncoding RNAs of approximately 21 nt that regulate gene expression in plants post-transcriptionally by endonucleolytic cleavage or translational inhibition. miRNAs play essential roles in numerous developmental and physiological processes and many of them are conserved across species. Extensive studies of miRNAs have been done in a few model plants; however, less is known about the diversity of these regulatory RNAs in peanut (Arachis hypogaea L.), one of the most important oilseed crops cultivated worldwide.
  
  
  RESULTS
  A library of small RNA from peanut was constructed for deep sequencing. In addition to 126 known miRNAs from 33 families, 25 novel peanut miRNAs were identified. The miRNA* sequences of four novel miRNAs were discovered, providing additional evidence for the existence of miRNAs. Twenty of the novel miRNAs were considered to be species-specific because no homolog has been found for other plant species. qRT-PCR was used to analyze the expression of seven miRNAs in different tissues and in seed at different developmental stages and some showed tissue- and/or growth stage-specific expression. Furthermore, potential targets of these putative miRNAs were predicted on the basis of the sequence homology search.
  
  
  CONCLUSIONS
  We have identified large numbers of miRNAs and their related target genes through deep sequencing of a small RNA library. This study of the identification and characterization of miRNAs in peanut can initiate further study on peanut miRNA regulation mechanisms, and help toward a greater understanding of the important roles of miRNAs in peanut.
authors: Shandong Peanut Research Institute, Qingdao, People's Republic of China.
authors: Xiaoyuan
authors: X
authors: Chi
authors: Qingli
authors: Q
authors: Yang
authors: Xiaoping
authors: X
authors: Chen
authors: Jinyan
authors: J
authors: Wang
authors: Lijuan
authors: L
authors: Pan
authors: Mingna
authors: M
authors: Chen
authors: Zhen
authors: Z
authors: Yang
authors: Yanan
authors: Y
authors: He
authors: Xuanqiang
authors: X
authors: Liang
authors: Shanlin
authors: S
authors: Yu
mesh_terms: D010367:Arachis / Q000235:genetics* / Q000254:growth & development; D030541:Databases, Genetic; D020869:Gene Expression Profiling; D059014:High-Throughput Nucleotide Sequencing / Q000379:methods*; D035683:MicroRNAs / Q000032:analysis* / Q000235:genetics*; D009928:Organ Specificity; D018749:RNA, Plant / Q000032:analysis* / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction; D017423:Sequence Analysis, RNA / Q000379:methods*
chemical_list: D035683:MicroRNAs; D018749:RNA, Plant