The northern blot is used to study gene expression by detection of RNA (or isolated mRNA). A general blotting procedure starts with the separation of RNA by electrophoresis. The RNA can then be transferred to a nylon membrane through a capillary system and detected with a hybridization probe.
Subcellular fractionation is extremely useful for assessing protein localization. This protocol shows how to separate and prepare of cytoplasmic and nuclear extracts from mammalian cultured cells.