Abstract
Genetically encoded fluorescent calcium indicator proteins are useful tools to study calcium dynamics in cellular activities. We developed and reported properties of a novel fluorescence resonance energy transfer (FRET)-based calcium indicator protein, designated F2C. F2C has cyan- and yellow- fluorescent proteins linked with a calpain sensitive sequence, and membrane-associated sequence in N-terminus. Primary cultures of rat Purkinje cells were transiently infected with Sindbis virus encoded this protein and fluorescent image analysis was performed. The fluorescence signal from F2C was repeatedly changed when intracellular calcium concentration was altered.Here, we report the generation of transgenic mice expressing F2C under control of tetracycline regulation system and analysis of these transgenic mice. F2C expression in transgenic mice was regulated by tetracycline repressor protein (TetR). We also generated transgenic mice which express TetR under the control of HCN4 promoter. F2C transgenic mice were crossbred with HCN4 transgenic mice to generate F2C-expressing mice and two lines of these crossbreeding mice expressed F2C in olfactory receptor neuron. F2C showed over 15% ratio changes by KCl application in olfactory bulb slices of these mice. Furthermore, in vivo experiment, F2C showed over 10% ratio changes by ATP application. [J Physiol Sci. 2007;57 Suppl:S121]
