Mass Spectrometry Defines Lysophospholipids as Ligands for Chicken MHCY Class I Molecules.
J Immunol
; 210(1): 96-102, 2023 01 01.
Article
en En
| MEDLINE
| ID: mdl-36427007
ABSTRACT
Chicken (Gallus gallus) MHCY class I molecules are highly polymorphic yet substantially different from polymorphic MHC class I molecules that bind peptide Ags. The binding grooves in MHCY class I molecules are hydrophobic and too narrow to accommodate peptides. An earlier structural study suggested that ligands for MHCY class I might be lipids, but the contents of the groove were not clearly identified. In this study, lysophospholipids have been identified by mass spectrometry as bound in two MHCY class I isoforms that differ substantially in sequence. The two isoforms, YF1*7.1 and YF1*RJF34, differ by 35 aa in the α1 and α2 domains that form the MHC class I ligand binding groove. Lyso-phosphatidylethanolamine (lyso-PE) 181 was the dominant lipid identified in YF1*7.1 and YF1*RJF34 expressed as recombinant molecules and renatured with ß2-microglobulin in the presence of a total lipid extract from Escherichia coli. Less frequently detected were lyso-PE 171, lyso-PE 161, and lysophosphatidylglycerols 171 and 160. These data provide evidence that lysophospholipids are candidate ligands for MHCY class I molecules. Finding that MHCY class I isoforms differing substantially in sequence bind the same array of lysophospholipids indicates that the amino acid polymorphism that distinguishes MHCY class I molecules is not key in defining ligand specificity. The polymorphic positions lie mostly away from the binding groove and might define specificity in interactions of MHCY class I molecules with receptors that are presently unidentified. MHCY class I molecules are distinctive in bound ligand and in display of polymorphic residues.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Antígenos de Histocompatibilidad Clase I
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Pollos
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Año:
2023
Tipo del documento:
Article