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Cutting edge: murine UL16-binding protein-like transcript 1: a newly described transcript encoding a high-affinity ligand for murine NKG2D.

Leonidas N Carayannopoulos·Olga V Naidenko·Daved H Fremont·Wayne M Yokoyama
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Abstract

Murine NKG2D is known to recognize H60 and five RAE1 variants. The human homologue recognizes both inducible MHC class I chain-related gene and constitutive (UL16-binding protein (ULBP)) ligands. Widely expressed, the latter are thought to mark transformed or infected cells for destruction by NK cells in the context of down-regulated cell surface class I (i.e., the "missing self"-response). Unlike MIC and ULBP however, mRNA for the murine ligands appears only in very limited contexts in the mature animal. In this study, we describe a NKG2D ligand termed "murine ULBP-like transcript 1 (MULT1) whose mRNA appears to be widely expressed in adult parenchyma. This molecule possesses MHC class I-like alpha1 and alpha2 domains as well as a large cytoplasmic domain. Recombinant MULT1 binds NKG2D with relatively high affinity (K(D) approximately 6 nM) and low k(off) (approximately 0.006s(-1)). Expression of MULT1 by normally resistant RMA cells results in their susceptibility to lysis by C57BL/6 splenocytes.

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Amino Acid SequenceAnimalsCarrier ProteinsCytotoxicity, ImmunologicHistocompatibility Antigens Class ILigandsMembrane ProteinsMiceMice, Inbred C57BLMolecular Sequence DataNK Cell Lectin-Like Receptor Subfamily KProtein BindingProtein Structure, TertiaryRNA, MessengerReceptors, ImmunologicReceptors, Natural Killer CellSpleenTumor Cells, CulturedJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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Leonidas N Carayannopoulos, Olga V Naidenko, Daved H Fremont, Wayne M Yokoyama. 2002-10-15. Cutting edge: murine UL16-binding protein-like transcript 1: a newly described transcript encoding a high-affinity ligand for murine NKG2D.. https://doi.org/10.4049/jimmunol.169.8.4079

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