PDBsum entry 1hla

Histocompatibility antigen

PDB id: 1hla

Contents

Protein chains

270 a.a.*

97 a.a.*

* C-alpha coords only

References listed in PDB file

Key reference

Title

Structure of the human class I histocompatibility antigen, Hla-A2.

Authors

P.J.Bjorkman, M.A.Saper, B.Samraoui, W.S.Bennett, J.L.Strominger, D.C.Wiley.

Ref.

Nature, 1987, 329, 506-512. [DOI no: 10.1038/329506a0]

PubMed id

3309677

Abstract

The class I histocompatibility antigen from human cell membranes has two structural motifs: the membrane-proximal end of the glycoprotein contains two domains with immunoglobulin-folds that are paired in a novel manner, and the region distal from the membrane is a platform of eight antiparallel beta-strands topped by alpha-helices. A large groove between the alpha-helices provides a binding site for processed foreign antigens. An unknown 'antigen' is found in this site in crystals of purified HLA-A2.

Figure 2.
Fig 2. Schematic representation of the structure of HLA-A2.

Figure 6.
Fig 6. Van der Waals surface representation of the top of the HLA-A2 molecules (a) showing the deep groove identified as the antigen recognition site ans the electron density (b) found in this site in crystals of HLA-A2.

The above figures are reprinted by permission from Macmillan Publishers Ltd: Nature (1987, 329, 506-512) copyright 1987.

Secondary reference #1

Title

The foreign antigen binding site and t cell recognition regions of class i histocompatibility antigens.

Authors

P.J.Bjorkman, M.A.Saper, B.Samraoui, W.S.Bennett, J.L.Strominger, D.C.Wiley.

Ref.

Nature, 1987, 329, 512-518.

PubMed id

2443855

Secondary reference #2

Title

Crystallization and X-Ray diffraction studies on the histocompatibility antigens hla-A2 and hla-A28 from human cell membranes.

Authors

P.J.Bjorkman, J.L.Strominger, D.C.Wiley.

Ref.

J Mol Biol, 1985, 186, 205-210. [DOI no: 10.1016/0022-2836(85)90271-2]

PubMed id

3878413

Figure 1.
Figure 1. Comparison of P2, and P2,2,2, transforms. Upper left: A 6'' screened precession photograph taken from a 1'2, crystal with the X-ray beam parallel to the monoclinic [102] axis. Upper right: A 6'' screened precession photograph taken from a P2,2,2, crystal with the X-ray beam parallel to the orthorhombic c axis (MO). Lower left: The 2 photographs are superimposed to demonstrate that the reciprocal lattices are sampled in identical position. Lower right: The 2 photographs are superimposed, but offset slightly. to demonstrate that the 2 reciprocal lattices have similar intensity distributions.

Figure 3.
Figure 3. Proposed model for the domain organization of HLA-A. Crystallographic evidence suggests that the molecule is approximately 2-fold symmetric, implying that the homologous domains of HLA are paired al to ~2, and cr3 to /?,-micoglobulin (/&m). This pairing of domains has been suggested, based on the similarities between class I and class II antigens (see e.g. Kaufman et al., 1984).

The above figures are reproduced from the cited reference with permission from Elsevier