Monitoring Notch activity in the mouse.

Several laboratories have developed genetic methods to monitor Notch activity in developing and adult mice. These approaches have been useful in identifying Notch signaling with high temporal and spatial resolution. This research has contributed substantially to our understanding of the role of Notch in cell specification and cellular physiology. Here, we present two protocols to monitor Notch activity in the mouse brain: (1) by intraventricular electroporation and (2) by intracranial viral injections of Notch reporter constructs. These methods allow monitoring of Notch signaling in specific brain regions from development to adulthood. In addition, using the appropriate modifications, the Notch reporter systems can also be used to monitor Notch activity in other organs of the mouse such as retina, skin, skeletal muscle, and cancer cells.