Fig. 1.

HSF2 interacts with Cul3. a The segment of Cul3 identified as an HSF2-interacting clone comprises amino acids 161–293 of this protein. Also shown are the Cul3 regions that interact with BTB domain proteins and Roc1. b β-galactosidase activity was measured in extracts of yeast strain pJ69-4A transformed with a pVP16 plasmid containing amino acids 161–293 of Cul3 and pGBD-HSF2, pGBD-HSF1, or empty pGBD-C1 plasmid. Data are presented as means ±SEM (n = 3). c Extracts of HeLa cells were subjected to immunoprecipitation with antibodies to Cul3 or non-specific IgG, followed by Western blot using HSF2 antibodies. d³⁵S-labeled in vitro translated Cul3 was incubated with GST-HSF2 and GST bound to glutathione-agarose beads. After washing, the amount of bound ³⁵S-labeled Cul3 was determined by SDS-PAGE and autoradiography (upper panel). The amounts of GST-HSF2 and GST bound to the beads were determined by anti-GST Western blot (lower panel)