Table 2. Fluorescence Parameters Including Lifetime, Average Degree of Adaptor Binding, and Relative Brightness for EGF-Treated Live Cells Expressing Both EGFR–eGFP and Grb2–mRFP.

experiment	τphasea	τmodb	fractionboundc	CDboundd	CDfreed	relative brightnesse
1	1.41	2.20	0.86	23	23	5.9
2	1.60	2.51	0.81	11	16	6.2
3	1.46	2.32	0.85	25	42	9.3
4	1.84	2.73	0.72	5.5	10	4.7
5	1.92	2.87	0.69	5.4	9.2	3.8
6	2.37	3.03	0.42	0.9	4.1	3.3
average			0.725	11.7	17.3	5.5
SEM			0.06	4	5	0.9

^aLifetime calculated from the phase of the fluorescence at 40 MHz (±0.011 ns).

^bLifetime calculated from the modulation of the fluorescence at 40 MHz (±0.015 ns).

^cFraction of receptors bound to adaptor (i.e., fraction EGFR–eGFP bound to Grb2–mRFP).

^dCluster densities or number of aggregates per square micrometer. The label “bound” refers to images containing only EGFR–eGFP bound to Grb2–mRFP. The label “free” refers to images containing only EGFR–eGFP uncomplexed with Grb2–mRFP.

^eRelative brightness (RB) of EGFR–eGFP/Grb2–mRFP complexes compared to uncomplexed EGFR–eGFP. Calculated from the equation RB = (fraction)g(0)_bound/(1 – fraction)g(0)_free