FIGURE 7:

Cav-1-WT and Cav-1-Y14F enhance the membrane interactions of Fyn-WT but not Fyn-Y531F. Cells were cotransfected with a vector encoding Fyn-WT-GFP or Fyn-Y531F-GFP, together with an expression vector for Cav-1-WT-mRFP, Cav-1-Y531F-mRFP, or empty vector (control). After 24 h, FRAP beam-size analysis was conducted on Fyn-WT-GFP (A, B) or Fyn-Y531F-GFP (C, D) as in Figure 1. Bars, means ± SEM of 30–60 measurements. (A, C) τ values. Significant effects of Cav-1 or Cav-1-Y14F were observed only on Fyn-WT-GFP. Asterisks indicate significant differences between the τ(63x) or τ(40x) values of the pairs indicated by the brackets, comparing τ values measured with the same beam size (**, p < 10⁻⁵; Student’s t test). (B, D) τ(40x)/τ(63x) ratios. Only the τ ratio of Fyn-WT without coexpression of Cav-1 was below the 2.28 value expected for lateral diffusion (*, p < 10⁻²). All other τ ratios were not significantly different from the 2.28 beam-size ratio, indicating stable interactions with the plasma membrane.