Figure 4.

Responsiveness of 293, CV-1, and FF12 cells coinfected with reporter and receptor-bearing retroviruses. (A) Schematic of receptor variant viral vectors (light shading) and the MS reporter virus (dark shading). Small, flanking empty boxes are LTRs, G418/l-histidinol are selectable markers, C/S is the cytomegalovirus or simian virus 40 promoter. Other nomenclature is described in the text. (B) β-Galactosidase histochemistry revealing positive MS-Z-infected cell types coinfected with receptor variants and treated with 1 μM ligand corresponding to the labels above (ligand), below (cell type), and to the left (receptor type) of the panels. Cell fields are taken from the approximate center of wells and are representative of staining. (C) Luciferase induction in MS-luc-infected cells analogous to the groups in B. Raw values are expressed as relative units normalized against LNCX values across cell types. Numbers at the end of bars represent fold induction relative to vehicle treatment.