Northern Blotting Technique for Detection and Expression Analysis 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. A brief account on the recent advancements for improving the sensitivity and efficiency of northern blot detection is also included in this chapter.