Whole-Mount and Section In Situ Hybridization in Mouse Embryos for Detecting mRNA Expression and Localization

In situ hybridization is defined as one of the most useful and powerful methods to know where genes (e.g., mRNA, ncRNA) of interest are expressed in tissues. Expression of mRNA can be detected as blue or dark purple signals though hybridization, immunoreaction and coloring steps. Genome-wide approaches in various model animals have been conducted thoroughly, and have led to new research areas aimed at uncovering novel gene functions in cell differentiation and development. To elucidate gene function, spatiotemporal gene expression analysis is very important. Here I describe protocols of whole-mount and section in situ hybridization, and emphasize the relevance of optimizing temperature, and sodium concentration, in hybridization buffer and substrate to improve signal.