Nonradioactive Plant Small RNA Detection Using Biotin-Labeled Probes.

Small noncoding RNAs are essential for gene expression at transcriptional and posttranscriptional levels. Northern blot is the most used method for small RNA detection in tissues. Here we present an improved protocol for the Northern blot-based small RNA detection from plant tissues by using biotin-labeled probes. MicroRNAs and small interfering RNAs derived from Arabidopsis and Oryza sativa, respectively, have been detected with this methodology. Results suggest that this method is sensitive and efficient enough to detect small RNAs from plant tissues by using as low as 5 μg of total RNA. Furthermore, biotin-labeled probes are safer and easier to store for long term than radiolabeled probes.