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. 2014 Mar 18;9(3):e92089. doi: 10.1371/journal.pone.0092089

Table 1. Effect of different mutations on the properties of EAAT1, EAAT2 (GLT-1) and EAAT3 (EAAC1) transporters.

Transporter Trans. Exch. Na+ aff.(s) Na+ aff. K+ int. Li+ int. Glu aff.* Asp aff.*
EAAT1 Wild-Type [4], [5] Yes Yes 20 mM Yes Yes 24 Inline graphicM 16 Inline graphicM
T131A [6] Yes N/S 1Red
S363R/R477M [4] No Yes 0Inc No 2Inc 2Inc
EAAT2 Wild-Type [7][10] Yes Yes 24 mM Yes No 5.3 Inline graphicM 2.8 Inline graphicM
Y403F [9] No Yes 1Inc No Yes WT WT
E404D [7] No Yes WT No
S440G [10] Yes Yes Yes Yes WT WT
EAAT3 Wild-Type [11][13] Yes Yes 8 mM 120 mM Yes Yes 14 Inline graphicM 14 Inline graphicM
T101A [14] Yes Yes 0Red N/S Yes 2Red
H296Q [15] Yes Yes WT Yes WT
N366Q [16] Yes Yes N/S Yes No 3Red 2Red
D368E [16] Yes Yes WT Yes No None 1Red
D368N [13] No Yes 0Red N/S No 2Red
N366D/D368N [16] No Yes No No 1Red 0Red
T370S [12], [17], [18] Yes Yes N/S 0Red Yes No 2Red WT
E374Q [11], [19] Yes Yes WT WT Yes WT
D440N [11] No No 1Red WT 2Red 1Red
D440E [20] Yes Yes 1Inc Yes Yes 1Inc 1Inc
D444C [21] No Yes WT WT
D444E [21] No Yes 0Inc WT WT
R445E [21] Yes Yes
R445S [22] Yes Yes WT Yes 1Inc 1Inc
R447C [23] No No Becomes a Na+ dependent serine/cysteine exchanger
N451S [17] Yes Yes N/S Yes No 2Red 1Red
D455N [11], [13], [24], [25] No Yes WT WT Yes Yes 0Inc 0Inc
D455S [24] No Yes 0Red No Yes WT 0Inc
D455E [24] No No
D455A [24][26] No No WT

Transporter/Exchanger functionality is given in the third and fourth columns. Columns 5 and 6 gives the Na+ affinity in the presence and absence of glutamate, respectively. Columns 7 and 8 specify K+ and Li+ interactions with the transporter. Glu and Asp affinities are given in the last two columns. For the affinities, N/S means no saturation of the binding site in the range considered, and nRed/nInc means reduction/increase in the ligand affinity by Inline graphic orders of magnitude (0, same order). Human sequences are used for EAAT3 which have one extra residue than the rat sequences employed in some experiments.

*All glutamate affinities measured at [Na+] between 100–150 mM.

Result for D-aspartate.

Enables succinate exchange, unlike wild-type.