The Tyrosine Kinase PYK-2/RAFTK Regulates Natural Killer (NK) Cell Cytotoxic Response, and Is Translocated and Activated upon Specific Target Cell Recognition and Killing

• Published in: The Journal of cell biology 2000-06, Vol.149 (6), p.1249-1261
• Main Authors: Sancho, David, Nieto, Marta, Llano, Manuel, Rodríguez-Fernández, José L., Tejedor, Reyes, Avraham, Shalom, Cabañas, Carlos, López-Botet, Miguel, Sánchez-Madrid, Francisco
• Format: Article
• Language: English
• Subjects: Animals; Antigens, CD - immunology; Cell Adhesion; Cell Line; Cell lines; Cell Movement; Cells; Cellular biology; Cytoskeletal Proteins - metabolism; Cytotoxicity; Cytotoxicity, Immunologic; Enzyme Activation; Fluorescent Antibody Technique; Focal Adhesion Kinase 2; Focal adhesions; Killer Cells, Natural - immunology; Killer Cells, Natural - metabolism; Lectins, C-Type; Membrane Glycoproteins - immunology; Molecules; Mutation; Natural killer cells; NK Cell Lectin-Like Receptor Subfamily D; Original; Paxillin; Phosphoproteins - metabolism; Physiological regulation; Protein-Tyrosine Kinases - genetics; Protein-Tyrosine Kinases - metabolism; Proteins; Receptors; Signal Transduction; T lymphocytes; Transfection; Vaccinia virus - genetics; ZAP-70 Protein-Tyrosine Kinase
• ISSN: 0021-9525; 1540-8140
• DOI: 10.1083/jcb.149.6.1249

The compartmentalization of plasma membrane proteins has a key role in regulation of lymphocyte activation and development of immunity. We found that the proline-rich tyrosine kinase-2 (PYK-2/RAFTK) colocalized with the microtubule-organizing center (MTOC) at the trailing edge of migrating natural killer (NK) cells. When polyclonal NK cells bound to K562 targets, PYK-2 translocated to the area of NK-target cell interaction. The specificity of this process was assessed with NK cell clones bearing activatory or inhibitory forms of CD94/NKG2. The translocation of PYK-2, MTOC, and paxillin to the area of NK-target cell contact was regulated upon specific recognition of target cells through NK cell receptors, controlling target cell killing. Furthermore, parallel in vitro kinase assays showed that PYK-2 was activated in response to signals that specifically triggered its translocation and NK cell mediated cytotoxicity. The overexpression of both the wt and a dominant-negative mutant of PYK-2, but not ZAP-70 wt, prevented the specific translocation of the MTOC and paxillin, and blocked the cytotoxic response of NK cells. Our data indicate that subcellular compartmentalization of PYK-2 correlates with effective signal transduction. Furthermore, they also suggest an important role for PYK-2 on the assembly of the signaling complexes that regulate the cytotoxic response.