The Cytochrome P450 3A43 Colorimetric Cell-Based ELISA provides a lysate-free, convenient, and high-throughput approach for sensitive detection of CytochromeP4503A43 protein expression profile in cells. The kit can be used for measuring the relative amounts of CytochromeP4503A43 in cultured cells as well as screening for the effects that various treatments, inhibitors (ie siRNA or chemicals), or activators have on CytochromeP4503A43.