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. Author manuscript; available in PMC: 2014 Sep 1.
Published in final edited form as: Anal Biochem. 2013 Jun 7;440(1):40–48. doi: 10.1016/j.ab.2013.04.033

Table 1.

FRAP and FCS results for proteins in FRT cells.

Cell type Protein Diffusion coefficient Mobile fraction n (cells)
a-FRTwt μOR–eGFP 4.7 ± 0.9 × 10−11 cm2/s 0.80 ± 0.04 12
a-FRTcav+ μOR–eGFP 4.1 ± 0.7 × 10−11 cm2/s 0.77 ± 0.02 12
a-FRTwt B2R–GFP 4.6 ± 0.6 × 10−11 cm2/s 0.80 ± 0.03 6
5.0 ± 0.6 × 10−9 cm2/s 22
a-FRTcav+ B2R–GFP 4.3 ± 0.6 × 10−11 cm2/s 0.79 ± 0.04 6
6.3 ± 0.7 × 10−9 cm2/s 21
b-FRTwt μOR–eGFP 5.7 ± 0.7 × 10−11 cm2/s 0.66 ± 0.04 12
3.2 ± 0.2 × 10−9 cm2/s 18
b-FRTcav+ μOR–eGFP 5.3 ± 0.7 × 10−11 cm2/s 0.49 ± 0.02 12
3.4 ± 0.2 × 10−9 cm2/s 16
b-FRTwt B2R–GFP 6.8 ± 0.7 × 10−11 cm2/s 0.64 ± 0.03 13
8.1 ± 0.8 × 10−9 cm2/s 80
b-FRTcav+ B2R–GFP 6.0 ± 0.8 × 10−11 cm2/s 0.51 ± 0.03 12
14.9 ± 0.9 × 10−9 cm2/s 86
b-FRTwt mm–eYFP 5.7 ± 0.6 × 10−11 cm2/s 0.82 ± 0.04 10
12.3 ± 0.3 × 10−9 cm2/s 81
b-FRTcav+ mm–eYFP 5.7 ± 0.3 × 10−11 cm2/s 0.82 ± 0.03 13
9.3 ± 0.3 × 10−9 cm2/s 60
b-FRTwt Gαq–eGFP 2.0 ± 0.2 × 10−10 cm2/s 0.64 ± 0.03 12
6.2 ± 0.3 × 10−9 cm2/s 75
b-FRTcav+ Gαq–eGFP 2.1 ± 0.2 × 10−10 cm2/s 0.62 ± 0.02 10
11.0 ± 0.1 × 10−9 cm2/s 74

Note: Shown are diffusion results for proteins and membrane marker (mm–eYFP) in FRTwt and FRTcav+ cells, where “a-” denotes the apical membrane and “b-” denotes the basolateral membrane. Values in normal font are those derived from FRAP measurements, whereas FCS measurements are in bold font. Diffusion coefficients assuming a 2 × 2 × 2-μm area reflect the beam dimensions in the x, y, and z planes and are thought to be appropriate for viewing membrane proteins diffusing in the basolateral membrane. Diffusion coefficients assuming a 2 × 4-μM area (not shown) were consistently 1.7 ± 0.1-fold lower in magnitude but the comparative results are unchanged. The data have a normal distribution as determined by Shapiro–Wilk test, and standard errors are shown. Differences in the mobile fractions for μOR and B2R in the basolateral membranes of FRTwt and FRTcav+ cells are significant (P < 0.001), whereas differences for mm–eYFP and Gαq–eGFP are not. Statistical analysis for the mobile fraction data can be found in Fig. 3C. These results show similar FRAP diffusion properties of the receptors in the absence and presence of caveolae.