Strain Detail: Balb/c.Eisuke-NES mice

The Balb/c.Eisuke-NES mice are transgenic mice with BALB/c background expressing cytoplasm-localized förster (or fluorescence) resonance energy transfer (FRET) biosensor EKAREV-NES monitoring ERK kinase activity under the control of CAG promoter in the whole body. Extracellular signal-regulated kinases (ERK) belonging to MAPK family are involved in the cellular growth and differentiation, especially play important roles in oncogene signal transduction cascade. It is possible to measure ERK kinase activity spatially and temporally in fetal or adult various tissues by live imaging observation of this strain in the two-photon microscopy. This strain expects not only to analyze the signal transduction cascade in live animals, but also to apply drug development such as the pharmacodynamic analysis targeting signal molecules because these mice show rich expression in primary cultured cells derived from various tissues. Cytoplasm-localized FRET biosensors are useful for the observation of cell shapes, whereas nucleus-localized FRET biosensors are better choices for comparison of ERK activity among cell lines derived from epithelial tissues. FRET biosensors generally can't be used for fixed samples.