Table 1

Protein-protein interactions detected with the yeast two-hybrid assay

HIS3β-GalONPG
pACT2-ABP:pGBT9-D2(211–372)++++65 ± 8.7 (3)
pGBT9-ABP: pACT2-D2 (211–372)++++
pACT2-ABP: pGBT9-D2s (211–343)++++
pACT2-ABP: pGBT9-D2Δ314–368
pACT2-ABP: pGBT9-D3(210–375)++++++93
pGBT9-ABP: pACT2-D3 (210–375)++++++
pACT2-ABP: pGBT9-D4.4 (214–346) 0.06
pACT2-ABP: pGBT9-D1 (215–272) 0.1
pACT2-ABP: pGBT9
pACT2-ABP: pGBT9-D2S358D++34 ± 6.1 (3)1-150

Yeast strain Y190 cells were cotransformed with expression vectors pACT2 and pGBT9 encoding either the third cytoplasmic loops from various dopamine receptors or ABP-280 (1779-2134). Controls for protein expression include a consistently observed growth of transformed yeast on synthetic dextrose plates lacking essential amino acids, tryptophan and leucine, which are encoded by each plasmid. HIS3 indicates yeast colony growth on plates lacking tryptophan, leucine, and histidine. β-Gal indicates a color reaction of β-galactosidase filter assay. The intensity of protein-protein interaction was quantified using ONPG (o-nitrophenyl β-d galactopyranoside) as a substrate. The numbers shown in the ONPG assay are the arbitrary units of β-galactosidase activity.

    • ONPG, o-nitrophenyl β-d-galactopyranoside.

    • 1-150P < .05, D2S358D versus D2, unpaired Student's t test.