Tg(Thy1-Clomeleon)1Gjau

A transgenic construct containing Clomeleon, a fluorescent fusion protein containing CFP and topaz YFP, under the control of the mouse Thy1, thymus cell antigen 1, theta, promoter (Thy1.2) was injected into fertilized ICR mouse eggs. Founder line CLM1 was subsequently established. Transgenic mice express Clomeleon, a fluorescent fusion protein containing CFP and YFP (topaz) that acts as a ratiometric indicator for chloride ions, under the control of the mouse Thy1, thymus cell antigen 1, theta, promoter (Thy1.2). Transgene expression in founder line CLM1 is detected at high levels in the mitral cells of the olfactory bulb, layer 5 of the neocortex, hippocampal dentate gyrus and CA1 region, amygdala, cerebellar granule cells, and retinal bipolar cells. No expression is detected in cerebellar mossy fibers, Purkinje cells or nuclei. In the presence of low chloride ion concentrations, YFP fluoresces as a FRET (Fluorescence Resonance Energy Transfer ) acceptor for CFP. As the chloride ion concentration increases, YFP fluorescence decreases and CFP fluorescence increases. Using an appropriate calibration curve, the ratio of YFP and CFP fluorescence peaks indicate [Cl-]. (J:166510)