Fig. 7. Armadillo associates with Notch in Drosophila embryos. Notch protein was immunoprecipitated from wild-type embryos and the presence of associated proteins was assessed by western blot. The majority of Notch protein present in embryo lysate and immunoprecipitated was the full-length protein (>250 kDa) which, in Drosophila is the predominant form of Notch at the cell surface (Kidd and Lieber, 2002). Detected in association with immunoprecipitated Notch were both Armadillo (middle panel) and Dishevelled (upper panel) protein. The lane labelled `lysate' represents a fifth of the total protein added to the immunoprecipitation reaction. Immunoprecipitated Notch reflects about 5-10% of the total Notch and associated with this is 0.5-3% of the total Armadillo and less than 0.5% of the total Dishevelled. Given that the pool of Armadillo associated with Notch is not associated with E-cadherin it is not surprising that this Notch-associated fraction of Armadillo is only a small proportion of the total cellular Armadillo.