title: Identification of putative novel O-glycosylations in the NK killer receptor Ncr1 essential for its activity.
abstract: Natural killer (NK) cells kill tumor and virus-infected cells using activating NK cell receptors. One of the major NK-activating receptors is NKp46 and its mouse ortholog Ncr1. NKp46/Ncr1 is expressed exclusively on NK cells and on a subset of innate lymphoid cells. NKp46/Ncr1 was shown to be involved in a myriad of pathologies and immunological settings. Specifically, NKp46/Ncr1 was shown to interact with the viral hemagglutinin (HA) protein and with an unknown tumor/cellular ligand. NKp46 and Ncr1 are structurally similar; however, they are substantially different in their glycosylation patterns. Although the human NKp46 carries both O- and N-glycosylations that are essential for its activity, the mouse Ncr1 was predicted to have N-linked glycosylations only. Here we discovered using prediction algorithms and high-performance liquid chromatography analysis that Ncr1 carries two putative novel O-glycosylations, one of which (Thr 225) is conserved in NKp46. We next used surface plasmon resonance, biochemical, mutational and functional in vitro and in vivo assays to demonstrate that the putative O-glycosylations of Ncr1 are critical for its function.
authors.affiliation: The Lautenberg Center for General and Tumor Immunology, The Hebrew University Hadassah Medical School, The Institute of Medical Research Israel Canada (IMRIC) , Jerusalem, Israel.
authors.forename: Ariella
authors.initials: A
authors.lastname: Glasner
authors.affiliation: Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev , Beer-Sheva, Israel.
authors.forename: Ziv
authors.initials: Z
authors.lastname: Roth
authors.affiliation: The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University , Ramat Gan, Israel.
authors.forename: Alexander
authors.initials: A
authors.lastname: Varvak
authors.affiliation: Department of Histology and Embryology Center for Proteomics, Faculty of Medicine, University of Rijeka , B. Branchetta, Rijeka, Croatia.
authors.forename: Antonija
authors.initials: A
authors.lastname: Miletic
authors.affiliation: The Lautenberg Center for General and Tumor Immunology, The Hebrew University Hadassah Medical School, The Institute of Medical Research Israel Canada (IMRIC) , Jerusalem, Israel.
authors.forename: Batya
authors.initials: B
authors.lastname: Isaacson
authors.affiliation: The Lautenberg Center for General and Tumor Immunology, The Hebrew University Hadassah Medical School, The Institute of Medical Research Israel Canada (IMRIC) , Jerusalem, Israel.
authors.forename: Yotam
authors.initials: Y
authors.lastname: Bar-On
authors.affiliation: Department of Histology and Embryology Center for Proteomics, Faculty of Medicine, University of Rijeka , B. Branchetta, Rijeka, Croatia.
authors.forename: Stipan
authors.initials: S
authors.lastname: Jonjic
authors.affiliation: Avram and Stella Goldstein-Goren Department of Biotechnology Engineering, Ben-Gurion University of the Negev , Beer-Sheva, Israel.
authors.forename: Isam
authors.initials: I
authors.lastname: Khalaila
authors.affiliation: The Lautenberg Center for General and Tumor Immunology, The Hebrew University Hadassah Medical School, The Institute of Medical Research Israel Canada (IMRIC) , Jerusalem, Israel.
authors.forename: Ofer
authors.initials: O
authors.lastname: Mandelboim