FIG. 2.

Δcag1 cells do not respond to the α-factor pheromone. Opaque cells were cultured in the presence of α-factor (+ pheromone) as described in Materials and Methods. Cells from the MTLa strain 3294 responded to the pheromone with the typical formation of unconstricted projections (shmoos). However, no morphological change was observed for the Δcag1 cells from the strain CA114. Similar results were also obtained for the other Δcag1 strain, CA116 (data not shown). Cells from the strains with CAG1 reintegrated (Δcag1+CAG1; CA121 and CA122) had a response similar to that of the wild-type (wt) parent strain 3294 (data not shown for the CA122 strain). Typical shmoos are highlighted with black arrows. The pictures were taken after 6 h of incubation with the pheromone. Similar results were also obtained after 4 h of incubation with the pheromone (data not shown).