Fig. 4. (A) The interaction between Dpit47 and DNA polymerase is stabilised by geldanamycin (g) and destabilised by ATP. Dpit47 was immunoprecipitated from crude embryo extract with anti-Dpit47 antibody cross-linked to protein A sepharose and eluted with 250 mM Nacl as in Fig. 2. The eluates were analysed on western blots using polyclonal anti-DNA polymerase antibody. (a) Dpit47 immunoprecipitates were carried out either in the presence (+g) or absence (-) of 1 µg/ml geldanamycin as described in materials and methods. (b) Dpit47 immunoprecipitates were carried out as above either in the presence of 1 µg/ml geldanamycin (+g) or 1 mM ATP (+ATP). (B) The interaction between Dpit47 and Hsp70 is destabilised by ATP. The 500 mM washed pellets of the immunoprecipitation as described above were analysed on SDS-PAGE and stained with Coomassie blue. The bands corresponding to Hsp90 Hsp70 and Dpit47 are shown. a, no treatment of the immunoprecipitate; b, treatment with geldanamycin; c, treatment with ATP.