The CDK5R2 Colorimetric Cell-Based ELISA is a convenient, lysate-free, high throughput and sensitive assay kit that can detect CDK5R2 protein expression profile in cells. The kit can be used for measuring the relative amounts of CDK5R2 in cultured cells as well as screening for the effects that variuos treatments, inhibitors (ie siRNA or chemicals), or activators have on CDK5R2.