Figure 3.

Immunofluorescence localization of myc-tagged wild-type and constitutively active α-factor receptors. Various myc-tagged α-factor receptors were expressed from their normal promoters on centromere-containing plasmids (pRS314 derivatives) in a ste2Δ mutant (KBY16). Cells carrying a control plasmid (expressing untagged α-factor receptors; panel A), or plasmids expressing myc-tagged wild-type (panel B) or constitutively active α-factor receptors (ste2P258L-myc, panel C; ste2P258Y-myc, panel D) were prepared for indirect immunofluorescence using 9E10 monoclonal antibodies specific for the c-myc epitope. Cells expressing the ste2P258Y-myc allele were misshapen, resembling the morphology of pheromone-treated wild-type cells. Bar, 5 μm.