Source was live S2 cells and extract of S2 cells; proteins produced from transfected constructs.

Physical interaction of proteins expressed on the surface of cells is inferred from the presence or absence of GFP signal after cells have been washed numerous times.

Source was cell extract of S2 cell line; bait produced from transfected construct; prey produced from transfected construct.

Membrane insoluble and cleavable 3,3\'- Dithiobis (sulfosuccinimidylpropionate) (DTSSP) was used to cross-link proteins interacting at the cell surface for this experiment.