A non-radioactive method for small RNA detection by northern blotting

BACKGROUND: Small non-coding RNAs are essential regulators of gene expression at the transcriptional and posttranscriptional levels. High-throughput sequencing has revealed thousands of predicted small RNAs; however, only a few of these have been well characterized. Northern blotting is the most convincing method for small RNA validation. FINDINGS: In this study, we improved the Northern blot method by using biotin-labeled probes. miRNAs and siRNAs derived from both Arabidopsis thaliana and Oryza sativa were investigated. The results suggest that this improved method is sensitive and efficient, with approximately 5 μg of total RNA being sufficient for detection. Furthermore, long-term storage of probes labeled in this manner is more convenient, less contaminative and degradative compared with traditional probes. CONCLUSIONS: This protocol is an alternative strategy for small RNA detection and represents an efficient means of researching small RNAs. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12284-014-0026-1) contains supplementary material, which is available to authorized users.