Northern blot analysis for expression profiling of mRNAs and small RNAs.

Northern analysis is a conventional but gold standard method for detection and quantification of gene expression changes. It not only detects the presence of a transcript but also indicates size and relative comparison of transcript abundance on a single membrane. In recent years, it has been aptly adapted to validate and study the size and expression of small noncoding RNAs. Here, we describe protocols employed in our laboratory for conventional northern analysis with total RNA/mRNA to study gene expression and validation of small noncoding RNAs using low molecular weight fraction of RNAs.