title: The Raf-like Kinase ILK1 and the High Affinity K+ Transporter HAK5 Are Required for Innate Immunity and Abiotic Stress Response.
abstract: Plant perception of pathogen-associated molecular patterns (PAMPs) and other environmental stresses trigger transient ion fluxes at the plasma membrane. Apart from the role of Ca(2+) uptake in signaling, the regulation and significance of PAMP-induced ion fluxes in immunity remain unknown. We characterized the functions of INTEGRIN-LINKED KINASE1 (ILK1) that encodes a Raf-like MAP2K kinase with functions insufficiently understood in plants. Analysis of ILK1 mutants impaired in the expression or kinase activity revealed that ILK1 contributes to plant defense to bacterial pathogens, osmotic stress sensitivity, and cellular responses and total ion accumulation in the plant upon treatment with a bacterial-derived PAMP, flg22. The calmodulin-like protein CML9, a negative modulator of flg22-triggered immunity, interacted with, and suppressed ILK1 kinase activity. ILK1 interacted with and promoted the accumulation of HAK5, a putative (H(+))/K(+) symporter that mediates a high-affinity uptake during K(+) deficiency. ILK1 or HAK5 expression was required for several flg22 responses including gene induction, growth arrest, and plasma membrane depolarization. Furthermore, flg22 treatment induced a rapid K(+) efflux at both the plant and cellular levels in wild type, while mutants with impaired ILK1 or HAK5 expression exhibited a comparatively increased K(+) loss. Taken together, our results position ILK1 as a link between plant defense pathways and K(+) homeostasis.
authors.affiliation: The Boyce Thompson Institute for Plant Research, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Biochemistry, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, Missouri 65211 (N.A., J.T.T.); Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana 70803 (R.D., N.K.); and Robert W. Holley Center for Agriculture and Health, Agricultural Research Service, US Department of Agriculture, Cornell University, Ithaca, New York 14853 (A.E.C., M.A.P., L.V.K.).
authors.forename: Elizabeth K
authors.initials: EK
authors.lastname: Brauer
authors.affiliation: The Boyce Thompson Institute for Plant Research, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Biochemistry, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, Missouri 65211 (N.A., J.T.T.); Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana 70803 (R.D., N.K.); and Robert W. Holley Center for Agriculture and Health, Agricultural Research Service, US Department of Agriculture, Cornell University, Ithaca, New York 14853 (A.E.C., M.A.P., L.V.K.).
authors.forename: Nagib
authors.initials: N
authors.lastname: Ahsan
authors.affiliation: The Boyce Thompson Institute for Plant Research, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Biochemistry, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, Missouri 65211 (N.A., J.T.T.); Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana 70803 (R.D., N.K.); and Robert W. Holley Center for Agriculture and Health, Agricultural Research Service, US Department of Agriculture, Cornell University, Ithaca, New York 14853 (A.E.C., M.A.P., L.V.K.).
authors.forename: Renee
authors.identifier: 0000-0002-1674-1247
authors.initials: R
authors.lastname: Dale
authors.affiliation: The Boyce Thompson Institute for Plant Research, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Biochemistry, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, Missouri 65211 (N.A., J.T.T.); Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana 70803 (R.D., N.K.); and Robert W. Holley Center for Agriculture and Health, Agricultural Research Service, US Department of Agriculture, Cornell University, Ithaca, New York 14853 (A.E.C., M.A.P., L.V.K.).
authors.forename: Naohiro
authors.initials: N
authors.lastname: Kato
authors.affiliation: The Boyce Thompson Institute for Plant Research, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Biochemistry, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, Missouri 65211 (N.A., J.T.T.); Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana 70803 (R.D., N.K.); and Robert W. Holley Center for Agriculture and Health, Agricultural Research Service, US Department of Agriculture, Cornell University, Ithaca, New York 14853 (A.E.C., M.A.P., L.V.K.).
authors.forename: Alison E
authors.initials: AE
authors.lastname: Coluccio
authors.affiliation: The Boyce Thompson Institute for Plant Research, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Biochemistry, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, Missouri 65211 (N.A., J.T.T.); Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana 70803 (R.D., N.K.); and Robert W. Holley Center for Agriculture and Health, Agricultural Research Service, US Department of Agriculture, Cornell University, Ithaca, New York 14853 (A.E.C., M.A.P., L.V.K.).
authors.forename: Miguel A
authors.identifier: 0000-0002-7166-1848
authors.initials: MA
authors.lastname: Piñeros
authors.affiliation: The Boyce Thompson Institute for Plant Research, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Biochemistry, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, Missouri 65211 (N.A., J.T.T.); Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana 70803 (R.D., N.K.); and Robert W. Holley Center for Agriculture and Health, Agricultural Research Service, US Department of Agriculture, Cornell University, Ithaca, New York 14853 (A.E.C., M.A.P., L.V.K.).
authors.forename: Leon V
authors.identifier: 0000-0003-3416-089X
authors.initials: LV
authors.lastname: Kochian
authors.affiliation: The Boyce Thompson Institute for Plant Research, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Biochemistry, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, Missouri 65211 (N.A., J.T.T.); Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana 70803 (R.D., N.K.); and Robert W. Holley Center for Agriculture and Health, Agricultural Research Service, US Department of Agriculture, Cornell University, Ithaca, New York 14853 (A.E.C., M.A.P., L.V.K.).
authors.forename: Jay J
authors.initials: JJ
authors.lastname: Thelen
authors.affiliation: The Boyce Thompson Institute for Plant Research, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, New York 14853 (E.K.B., S.C.P.); Department of Biochemistry, University of Missouri, Christopher S. Bond Life Sciences Center, Columbia, Missouri 65211 (N.A., J.T.T.); Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana 70803 (R.D., N.K.); and Robert W. Holley Center for Agriculture and Health, Agricultural Research Service, US Department of Agriculture, Cornell University, Ithaca, New York 14853 (A.E.C., M.A.P., L.V.K.) scp319@msstate.edu.
authors.forename: Sorina C
authors.identifier: 0000-0001-5780-8252
authors.initials: SC
authors.lastname: Popescu
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000276:immunology* / Q000382:microbiology / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D002147:Calmodulin / Q000378:metabolism; D005408:Flagellin / Q000494:pharmacology; D006706:Homeostasis / Q000187:drug effects; D007113:Immunity, Innate / Q000187:drug effects; D007477:Ions; D008353:Mannitol / Q000494:pharmacology; D008954:Models, Biological; D009154:Mutation / Q000235:genetics; D009995:Osmosis / Q000187:drug effects; D010935:Plant Diseases / Q000276:immunology / Q000382:microbiology; D057865:Plant Immunity / Q000187:drug effects; D030821:Plants, Genetically Modified; D011188:Potassium / Q000378:metabolism; D027961:Potassium-Hydrogen Antiporters / Q000378:metabolism*; D011485:Protein Binding / Q000187:drug effects; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry / Q000378:metabolism*; D021381:Protein Transport / Q000187:drug effects; D015398:Signal Transduction / Q000187:drug effects; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological / Q000187:drug effects; D013347:Subcellular Fractions / Q000187:drug effects / Q000378:metabolism; D014026:Nicotiana / Q000235:genetics; D000099200:Scaffold Protein ILK
chemical_list: D029681:Arabidopsis Proteins; D002147:Calmodulin; D005408:Flagellin; D007477:Ions; D008353:Mannitol; D011188:Potassium; D027961:Potassium-Hydrogen Antiporters; D017346:Protein Serine-Threonine Kinases; D012965:Sodium Chloride; D000099200:Scaffold Protein ILK; C465133:CaM9 protein, Arabidopsis; C501258:potassium transporter, Arabidopsis; C000622660:ILK1 protein, Arabidopsis