TABLE 1.
Summary of functional properties of GluN1-P532H-containing receptors.
| Parameters | Cells | Coexpressed with GluN2A | Coexpressed with GluN2B | ||
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| WT GluN1 | GluN1-P532H | WT GluN1 | GluN1-P532H | ||
| Glutamate EC50 [μM ] (n) | Oocytes | 6.4 (5.2, 7.5) (27) | 105 (85, 126) (26)* | 1.9 (1.4, 2.4) (12) | 82 (62, 102) (20)* |
| Glycine, EC50 [μM ] (n) | 1.8 (1.4, 2.1) (11) | 2.0 (1.6, 2.4) (12) | 0.45 (0.35, 0.54) (19) | 0.34 (0.24, 0.44) (16) | |
| Mg, IC50 [μM ] (n) ξ | 19 (16, 22) (16) | 22 (13, 30) (14) | 38 (23, 52) (7) | 35 (22, 48) (7) | |
| pH, %6.8/7.6 (n) γ | 44% (40%, 47%) (12) | 43% (39%, 46%) (11) | 19% (16%, 22%) (9) | 19% (16%, 23%) (13) | |
| Zinc, IC50 [nM ] (n) ϕ | 8.5 (6.8, 10) (12) | 4.1 (3.0, 5.2) (12)* | NA | NA | |
| % Inhibition by 300 nM zinc | 63% (59%, 68%) (12) | 62% (55%, 70%) (12) | NA | NA | |
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| Amplitude (peak, pA/pF) | HEK cells | 144 (71, 216) | 47 (17, 78) | 59 (23, 94) | 48 (22, 74) |
| Amplitude (SS, pA/pF) | 109 (56, 162) | 40 (17, 63) | 49 (21, 77) | 42 (19, 64) | |
| ISS/IPEAK, 1 mM glutamate | 0.77 (0.74, 0.79) | 0.88 (0.82, 0.93)* | 0.88 (0.82, 0.94) | 0.86 (0.79, 0.92) | |
| 10%–90% rise time (ms), 1 mM glutamate | 6.0 (4.7, 7.3) | 14 (10, 17)* | 12 (9.4, 15) | 13 (11, 15) | |
| τFAST deactivation (ms), 1 mM glutamate | 48 (33, 62) | 21 (13, 28)* | 536 (468, 605) | 24 (19, 28)* | |
| τSLOW deactivation (ms), 1 mM glutamate | 268 (83, 454) | 189 (29, 351) | 2,045 (1172, 2917) | 218 (55, 381)* | |
| %τFAST deactivation, 1 mM glutamate | 64% | 91% | 77% | 74% | |
| τW deactivation (ms), 1 mM glutamate | 66 (54, 77) | 26 (20, 31)* | 821 (723, 918) | 37 (30, 43)* | |
| Charge transfer, pA × ms/pF | 8,598 | 1,085 | 50,028 | 1,743 | |
| N | 7 | 7 | 7 | 8 | |
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| ISS/IPEAK, 1 μM glycine | HEK cells | 0.37 (0.24, 0.50) | 0.50 (0.35, 0.65) | NA | NA |
| τFAST desensitization (ms), 1 μM glycine | 326 (90, 562) | 102 (30, 174) | NA | NA | |
| τSLOW desensitization (ms), 1 μM glycine | 1481 (322, 2639) | 1961 (791, 3031) | NA | NA | |
| %τFAST desensitization (ms), 1 μM glycine | 53% | 57% | NA | NA | |
| τW desensitization (ms), 1 μM glycine | 757 (374, 1141) | 1041 (206, 1877) | NA | NA | |
| ISS/IPEAK, 30 μM glycine | 0.43 (0.26, 0.59) | 0.71 (0.54, 0.87) | NA | NA | |
| τFAST desensitization (ms), 30 μM glycine | 652 (425, 878) | 1423 (627, 2218) | NA | NA | |
| τSLOW desensitization (ms), 30 μM glycine | 1943 (783, 3104) | 2817 (893, 4741) | NA | NA | |
| %τFAST desensitization (ms), 30 μM glycine | 68% | 67% | NA | NA | |
| τW desensitization (ms), 30 μM glycine | 974 (667, 1282) | 1898 (882, 2915) | NA | NA | |
| N | 11 | 10 | NA | NA | |
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| %Potentiation by MTSEA # | Oocytes | 326% (267%, 385%) | 804% (679%, 929%) | NA | NA |
| POPEN (from MTSEA) | 0.26 (0.22, 0.30) | 0.11 (0.09, 0.11)* | NA | NA | |
| N | 41 | 34 | NA | NA | |
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| Surface/total ratio (β-lac) | HEK cells | 100% | 64% (55%, 74%)* | 100% | 67% (43%, 90%)* |
| Total protein % of WT (β-lac) | 100% | 110% (95%, 125%) | 100% | 193% (106%, 280%)* | |
| N | 5 | 5 | 7 | 7 | |
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| Synaptic charge transfer | 1.0 | 0.22 | NA | NA | |
| Nonsynaptic charge transfer | 1.0 | 0.004 | NA | NA | |
The data were expressed as mean (−95% CI, +95% CI) (n); CI, confidence interval; (n) is the number of oocytes or HEK cells.
*p < 0.05 indicated when the 95% confidence intervals of the datasets for the variant receptors do not overlap with the wild-type receptors.
ξHolding potential was −60 mV.
γPercentage of the current at pH 6.8 compared with that at pH 7.6.
ϕHolding potential was −20 mV.
#Evaluated by TEVC recordings on Xenopus oocytes, see the Section “Materials and Methods” and Figure 3.
NA, not available.