Interaction of the NK cell inhibitory receptor Ly49A with H-2Dd: identification of a site distinct from the TCR site

Immunity. 1999 Nov;11(5):591-601. doi: 10.1016/s1074-7613(00)80134-x.

Abstract

Natural killer cell function is controlled by interaction of NK receptors with MHC I molecules expressed on target cells. We describe the binding of bacterially expressed Ly49A, the prototype murine NK inhibitory receptor, to similarly engineered H-2Dd. Despite its homology to C-type lectins, Ly49A binds independently of carbohydrate and Ca2+ and shows specificity for MHC I but not bound peptide. The affinity of the Ly49A/H-2Dd interaction as determined by surface plasmon resonance is from 6 to 26 microM at 25 degrees C and is greater by ultracentrifugation at 4 degrees C. Biotinylated Ly49A stains H-2Dd-expressing cells. Competition experiments indicate that the Ly49A and T cell receptor (TCR) binding sites on MHC I are distinct, suggesting complex regulation of cells that bear both TCR and NK cell receptors.

MeSH terms

  • Animals
  • Antigens, Ly*
  • Binding Sites
  • Binding, Competitive
  • Biotinylation
  • Calcium / metabolism
  • Glycosylation
  • H-2 Antigens / metabolism*
  • Histocompatibility Antigen H-2D
  • Killer Cells, Natural / immunology*
  • Lectins, C-Type
  • Membrane Glycoproteins / chemistry
  • Membrane Glycoproteins / genetics
  • Membrane Glycoproteins / metabolism*
  • Mice
  • Mice, Inbred C57BL
  • Models, Molecular
  • NK Cell Lectin-Like Receptor Subfamily A
  • Peptide Fragments / metabolism
  • Protein Binding
  • Protein Folding
  • Protein Processing, Post-Translational
  • Protein Structure, Tertiary
  • Receptors, Antigen, T-Cell / metabolism
  • Receptors, NK Cell Lectin-Like
  • Recombinant Fusion Proteins / metabolism
  • Surface Plasmon Resonance
  • Ultracentrifugation

Substances

  • Antigens, Ly
  • H-2 Antigens
  • Histocompatibility Antigen H-2D
  • Klra1 protein, mouse
  • Lectins, C-Type
  • Membrane Glycoproteins
  • NK Cell Lectin-Like Receptor Subfamily A
  • Peptide Fragments
  • Receptors, Antigen, T-Cell
  • Receptors, NK Cell Lectin-Like
  • Recombinant Fusion Proteins
  • Calcium