Dopamine D1-D2 receptor heteromer signaling pathway in the brain: emerging physiological relevance

Table 1 Confocal FRET analysis of D1 and D2 receptor interaction

ROI	Donor of FRET	Acceptor of FRET	PFRET	FRET Efficiency	Distance between donor and acceptor (nm)
(1) Donor alone	13.944	0	0	0	10
2	842.685	562.542	529.703	0.357	5.91
3	804.879	488.573	474.042	0.351	5.9
4	830.377	569.241	535.203	0.353	5.924
5	720.099	436.039	410.781	0.319	6.269
6	898.475	482.132	444.885	0.311	6.171
7	964.916	460.029	407.186	0.247	6.875
8	1116.854	399.85	384.365	0.234	6.632
9	951.224	324.177	314.284	0.206	7.145
10	1076.73	341.095	326.925	0.2	7.153
11	976.861	227.299	216.367	0.149	7.789
12	1201.314	363.612	336.45	0.191	7.121
13	998.373	283.121	269.621	0.187	7.197
14	1017.225	303.213	287.876	0.2	6.987
15	816.347	166.339	156.562	0.129	8.069
16	806.034	265.133	251.731	0.19	7.393
17	815.063	349.81	338.709	0.252	6.792
18	833.344	485.752	382.262	0.257	6.946
(19)Non-Specific	95.52	83.573	35.284	0.086	9.168
Average	921.8117	382.821	356.88	0.243117	6.83958
SEM	33.82434	29.9949	27.1577	0.018620	0.165392

Confocal FRET analysis of figure 1 shows the relative expression of the donor (D2-Alexa 350, green) and acceptor (D1-Alexa 488, red). The analysis also shows the processed FRET (pFRET), the FRET efficiency and the distances separating the two fluorophore-tagged receptors in each microdomain (ROI), with averages and SEM in the bottom of the table. A distance ~10 nm or higher indicates no FRET.

ISSN: 1756-6606