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Correspondence between the IMGT unique numbering for G-DOMAIN and the different numberings (horizontal display)

Citing this page:
"IMGT unique numbering for MHC groove G-DOMAIN and MHC superfamily (MhcSF) G-LIKE-DOMAIN" M.-P., Lefranc et al., Dev. Comp. Immunol., 29, 917-938 (2005). PMID: 15936075 pdf with permission from Elsevier

The first line indicates the IMGT unique numbering for G-DOMAIN and G-LIKE-DOMAIN [1]. The other lines correspond to the numbering in mature MHC proteins.

A-STRAND AB-TURN B-STRAND
1.2 1.1 1 2 3 4 5 6 7 7A 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
G-ALPHA1 + + +       +
MHC class I [D1] - - 1 2 3 4 5 6 7 - 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
H       R
G-ALPHA      
MHC class II chain A [D1] 1 2 3 4 5 6 7 8 9 - 10 11 12 13 14 15 16 - - - - 17 18 19 20 21
H      
G-ALPHA2 (1,3) + + +      
MHC class I [D2] - - 91 92 93 94 95 96 97 - 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113
H C       R
G-BETA (3,4)      
MHC class II chain B [D1] - - 1 2 3 4 5 6 7 - 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
C       R

B-STRAND BC-TURN C-STRAND CD-TURN D-STRAND
24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
G-ALPHA1 + +          
MHC class I [D1] 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
         
G-ALPHA          
MHC class II chain A [D1] 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 - - 38 39 40 41 42 43 44 45
         
G-ALPHA2 (1) + +          
MHC class I [D2] 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 - - 130 131 132 133 134 135 136 137
         
G-BETA          
MHC class II chain B [D1] 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 - - 40 41 42 43 44 45 46 47
         

D-STRAND HELIX
49.1 49.2 49.3 49.4 49.5 50 51 52 53 54 54A 55 56 57 58 59 60 61 61A 61B 62 63 64 65 66 67
G-ALPHA1 T + T + T + +
MHC class I [D1] - - - - - 50 51 52 53 54 - 55 56 57 58 59 60 61 - - 62 63 64 65 66 67
G-ALPHA
MHC class II chain A [D1] - - - - - 46 47 48 49 50 - - - - - 51 52 53 - - 54 55 56 57 58 59
G-ALPHA2 + T + + T T T + T + +
MHC class I [D2] - - - - - 138 139 140 141 142 - 143 144 145 146 147 148 149 150 - 151 152 153 154 155 156
G-BETA (4)
MHC class II chain B [D1] - - - - - 48 49 50 51 52 - 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67
 

HELIX
68 69 70 71 72 72A 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 92A
G-ALPHA1 (2) T + T + + T + + + T +
MHC class I [D1] 68 69 70 71 72 - 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 - - -
N
G-ALPHA (2)
MHC class II chain A [D1] 60 61 62 63 64 - 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 -
N
G-ALPHA2 (1,3) T + T + T + +
MHC class I [D2] 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 -
C
G-BETA (3)
MHC class II chain B [D1] 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 - - - -
C

+ indicates MHC class I positions which are in contact with the peptide.
T indicates MHC class I positions which are in contact with the T cell receptor.

G-ALPHA1 (MHC class I domain 1, MHC class Iα1 in the literature).
G-ALPHA2 (MHC class I domain 2, MHC class Iα2 in the literature).
G-ALPHA (MHC class II chain A domain 1, MHC class IIα1 in the literature).
G-BETA (MHC class II chain B domain 1, MHC class IIβ1 in the literature).

More information:
IMGT notes:
  1. (1) The IMGT unique numbering for positions 1-39 and 73-92 of the G-ALPHA2 domains can be obtained very easily by substracting 90 from the mature protein (91-129 and 163-182) [1].
  2. (2) The glycosylation site (N, X, S/T) with asparagine N at IMGT position 86 is conserved in G-ALPHA1 and G-ALPHA. This site is also found in mouse MHCIa G-ALPHA2 [1].
  3. (3) The disulfide-linked cysteines at IMGT positions 11 and 74 are conserved in G-ALPHA2, G-ALPHA2-LIKE and G-BETA [1].
  4. (4) Particular gaps:
    • Homo sapiens HLA-DPB1: gaps at IMGT positions 19 and 20 in G-BETA [1].
    • Mus musculus H2-AB*02 (I-Aβk): gaps at IMGT positions 61A and 61B in G-BETA.
    These gaps have previously been identified by Brown et al. in an attempt to align MHC domains [2].
IMGT references:
  1. [1] Lefranc, M.-P. et al., Dev. Comp. Immunol., 29, 917-938 (2005). PMID: 15936075
  2. [2] Brown, J.H. et al., Nature, 332, 845-850 (1988). PMID: 3258651
See also:
Created:
30/07/2003
Last updated:
Wednesday, 10-Feb-2021 16:54:35 CET
Authors:
Nathalie Clavert, Marie-Paule Lefranc
Editor:
Chantal Ginestoux
Scientific officer:
Marie-Paule Lefranc