Comparison of expression levels and processing between transfected cells and endogenous Notch from dissected fly tissue. Western blotting to show the effect of Notch overexpression on Notch processing in S2 cells and quantification of the ratio of Notch fragments lacking ECD, i.e., transmembrane (TM) tethered/soluble ICD domains, located around 120 kD, to full-length protein around 300 kD. The graph below shows quantification from five repeats showing no change in ratio, up to a 20 ng limit used in this study. Characteristic fragmentation pattern of Notch (asterisks) is in common between endogenous Notch from tissue extracts and Notch expressed in S2 cells. Source data are available for this figure: SourceData FS2.