miChip: a microarray platform for expression profiling of microRNAs based on locked nucleic acid (LNA) oligonucleotide capture probes

Methods. 2007 Oct;43(2):146-52. doi: 10.1016/j.ymeth.2007.04.009.


As key regulators of post-transcriptional gene expression, it is important to monitor the expression of microRNAs (miRNA) in diverse physiological and pathophysiological processes. Here, we describe a method for sensitive and accurate microarray-based expression profiling of miRNAs. The protocol focuses on the use of locked nucleic acid (LNA)-modified capture probes. LNAs are bicyclic nucleotide analogues that significantly increase the melting temperature (T(m)) of hybrids with miRNAs. Mixed LNA/DNA capture probes thus can be designed for equal T(m)s for all miRNAs, which naturally cover a range between 45 and 74 degrees C. The protocols established are easy to apply, as they do not require RNA size selection and/or amplification of miRNAs. Moreover, they enable high affinity hybridizations yielding accurate signals that discriminate between single nucleotide differences and hence closely related miRNA family members.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Base Sequence
  • Gene Expression Profiling / methods*
  • MicroRNAs / genetics*
  • MicroRNAs / isolation & purification
  • Nucleic Acid Hybridization
  • Oligonucleotide Array Sequence Analysis / methods*
  • Oligonucleotide Probes* / genetics


  • MicroRNAs
  • Oligonucleotide Probes