Strain Detail: lox-PKAchu mice

The lox-PKAchu mice are transgenic mice expressing the probe which is consisted of cytoplasm-localized förster (or fluorescence) resonance energy transfer (FRET) biosensor monitoring PKA kinase activity added with lox-tdKeima. Protein kinase A (PKA, also known as the cyclic AMP-dependent protein kinase) is activated by cAMP which is raised intracellular concentration by stimuli of hormone or bioactive substance, and relays signal transduction received like hormones. This strain expresses Keima fluorescent protein under the control of CAG promoter in almost all tissues. These mice are able to switch expression tissue-specifically from Keima fluorescent protein to FRET biosensor by mating with tissue-specific Cre-expressed mouse. It's possible to measure PKA 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 apply drug development such as the pharmacodynamic analysis targeting signal molecules, because these mice are showed rich expression in primary cultured cells derived from various tissues. In the developmental stage, biosensor expression can be observed at almost all cells. FRET biosensor generally can't use for fixed samples.