Figure 8.
Morphometric measurements of gold-labeled PLCγ isoforms show wortmannin-sensitive translocation of PLCγ1, but not PLCγ2, to the plasma membrane. A) Percent of anti-PLCγ1 gold label within 60 nm of the plasma membrane of resting, control RBL-2H3 cells, followed by 2 or 10 min of antigen stimulation. B) Percent of anti-PLCγ1 gold label at the plasma membrane after 15 min wortmannin treatment, followed by 2 or 10 min of antigen stimulation. C) Percent of anti-PLCγ2 gold label at the plasma membrane of resting, control RBL-2H3 cells, followed by 2 or 10 min of antigen. Micrographs were blind-coded before counting; each experimental point represents the percent of total gold counts from replicate thin sections cut from blocks generated in 2 separate experiments. At least 1,000 gold particles were counted for each experimental condition.