, Volume 237, Issue 4, pp 1149–1161

Genome-wide identification and characterization of microRNA genes and their targets in flax (Linum usitatissimum)

Characterization of flax miRNA genes


  • Vitthal T. Barvkar
    • Biochemical Sciences DivisionCSIR-National Chemical Laboratory
  • Varsha C. Pardeshi
    • Biochemical Sciences DivisionCSIR-National Chemical Laboratory
  • Sandip M. Kale
    • Biochemical Sciences DivisionCSIR-National Chemical Laboratory
  • Shuqing Qiu
    • Plant Biotechnology Institute, NRC
  • Meaghen Rollins
    • Plant Biotechnology Institute, NRC
  • Raju Datla
    • Plant Biotechnology Institute, NRC
  • Vidya S. Gupta
    • Biochemical Sciences DivisionCSIR-National Chemical Laboratory
    • Biochemical Sciences DivisionCSIR-National Chemical Laboratory
Original Article

DOI: 10.1007/s00425-012-1833-5

Cite this article as:
Barvkar, V.T., Pardeshi, V.C., Kale, S.M. et al. Planta (2013) 237: 1149. doi:10.1007/s00425-012-1833-5


MicroRNAs (miRNAs) are small (20–24 nucleotide long) endogenous regulatory RNAs that play important roles in plant growth and development. They regulate gene expression at the post-transcriptional level by translational repression or target degradation and gene silencing. In this study, we identified 116 conserved miRNAs belonging to 23 families from the flax (Linum usitatissimum L.) genome using a computational approach. The precursor miRNAs varied in length; while most of the mature miRNAs were 21 nucleotide long, intergenic and showed conserved signatures of RNA polymerase II transcripts in their upstream regions. Promoter region analysis of the flax miRNA genes indicated prevalence of MYB transcription factor binding sites. Four miRNA gene clusters containing members of three phylogenetic groups were identified. Further, 142 target genes were predicted for these miRNAs and most of these represent transcriptional regulators. The miRNA encoding genes were expressed in diverse tissues as determined by digital expression analysis as well as real-time PCR. The expression of fourteen miRNAs and nine target genes was independently validated using the quantitative reverse transcription PCR (qRT-PCR). This study suggests that a large number of conserved plant miRNAs are also found in flax and these may play important roles in growth and development of flax.


LinseedMiRNAPromoter analysisDigital expression analysisGene clusterMiRNA target transcript

Supplementary material

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Supplementary material 1 (XLSX 67 kb)
425_2012_1833_MOESM2_ESM.pdf (3.7 mb)
Supplementary material 2 (PDF 3781 kb)
425_2012_1833_MOESM3_ESM.xlsx (288 kb)
Supplementary material 3 (XLSX 287 kb)
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Hierarchical representation of GO terms overrepresented in biological process (a), cellular component (b) and molecular function (c) categories generated by agriGO analysis. The boxes represent GO terms, GO id, term definition and statistical information and are color coded as per the level of significance (0.05). Non-significant terms are shown as white boxes. The degree of color saturation of a box is positively correlated to the enrichment level of the term. Solid, dashed, and dotted lines represent two, one and zero enriched terms at both ends connected by the line, respectively. The rank direction of the graph is set to from left to right (TIFF 3284 kb)

Copyright information

© Springer-Verlag Berlin Heidelberg 2013