title: Protein kinase D2 is a digital amplifier of T cell receptor-stimulated diacylglycerol signaling in naïve CD8⁺ T cells.
abstract: Protein kinase D2 (PKD2) is a serine and threonine kinase that is activated in T cells by diacylglycerol and protein kinase C in response to stimulation of the T cell receptor (TCR) by antigen. We quantified the activation of PKD2 at the single-cell level and found that this kinase acts as a sensitive digital amplifier of TCR engagement, enabling CD8(+) T cells to match the production of inflammatory cytokines to the quality and quantity of TCR ligands. There was a digital response pattern of PKD2 activation in response to TCR engagement, such that increasing the concentration and potency of TCR ligands increased the number of cells that exhibited activated PKD2. However, for each cell that responded to TCR stimulation, the entire cellular pool of PKD2 (~400,000 molecules) was activated. Moreover, PKD2 acted as an amplification checkpoint for antigen-stimulated digital cytokine responses and translated the differential strength of TCR signaling to determine the number of naïve CD8(+) T cells that became effector cells. Together, these results provide insights into PKD family kinases and how they act digitally to amplify signaling networks controlled by the TCR.
authors.affiliation: Division of Cell Signalling and Immunology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK.
authors.forename: María N
authors.initials: MN
authors.lastname: Navarro
authors.affiliation: Division of Cell Signalling and Immunology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK.
authors.forename: Carmen
authors.initials: C
authors.lastname: Feijoo-Carnero
authors.affiliation: MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK.
authors.forename: Alba Gonzalez
authors.initials: AG
authors.lastname: Arandilla
authors.affiliation: MRC Protein Phosphorylation and Ubiquitylation Unit, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK.
authors.forename: Matthias
authors.initials: M
authors.lastname: Trost
authors.affiliation: Division of Cell Signalling and Immunology, College of Life Sciences, University of Dundee, Dundee DD1 5EH, UK. d.a.cantrell@dundee.ac.uk.
authors.forename: Doreen A
authors.initials: DA
authors.lastname: Cantrell
mesh_terms: D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D051379:Mice; D018345:Mice, Knockout; D000091283:Protein Kinase D2; D011494:Protein Kinases / Q000235:genetics / Q000276:immunology*; D011948:Receptors, Antigen, T-Cell / Q000235:genetics / Q000276:immunology*; D015398:Signal Transduction / Q000235:genetics / Q000276:immunology*
chemical_list: D000091283:Protein Kinase D2; D011948:Receptors, Antigen, T-Cell; D011494:Protein Kinases