Premium
Production, crystallization, and preliminary X‐ray analysis of the human MHC class Ib molecule HLA‐E
Author(s) -
O'callaghan Christopher A.,
McMichael Andrew J.,
Bell John I.,
Blundell Charlie D.,
Jakobsen Bent K.,
Willcox Benjamin E.,
Tormo José,
Stuart David I.,
Jones E. Yvonne
Publication year - 1998
Publication title -
protein science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.353
H-Index - 175
eISSN - 1469-896X
pISSN - 0961-8368
DOI - 10.1002/pro.5560070525
Subject(s) - major histocompatibility complex , human leukocyte antigen , beta 2 microglobulin , mhc class i , t cell receptor , ligand (biochemistry) , crystallization , receptor , molecule , biology , chemistry , peptide , mhc restriction , crystallography , t cell , antigen , biochemistry , immune system , genetics , immunology , organic chemistry
Abstract HLA‐E is the first human class Ib major histocompatibility complex molecule to be crystallized. HLA‐E is highly conserved and almost nonpolymorphic, and has recently been shown to be the first specialized ligand for natural killer cell receptors. In functional studies, HLA‐E is unlike the class Ia MHC molecules in having tightly restricted peptide binding specificity. HLA‐E binds a limited set of almost identical leader sequence peptides derived from class Ia molecules and presents these at the cell surface for recognition by natural killer cell receptors. We now show that the extracellular region of HLA‐E forms a stable complex with β2 microglobulin and can be refolded around synthetic peptide. Crystals of this complex formed slowly over four to six months in the presence of ammonium sulphate. The crystals diffract to 2.85 Å with space group P3 I 21 and unit cell dimensions a = 182.2 Å, b = 182.2 Å, c = 88.4 Å.