title: Receptor-like protein kinase HvLysMR1 of barley (Hordeum vulgare L.) is induced during leaf senescence and heavy metal stress.
abstract: The Hordeum vulgare cDNA clone HvLysMR1 that encodes a putative receptor-like protein kinase was identified by restriction fragment differential display-polymerase chain reaction (PCR) comparing cDNA populations derived from mRNAs of primary leaves stressed with chromium for 48 h with controls. The full-length sequence codes for a protein with 622 amino acids which includes characteristic domains of lysine motif receptor-like kinases: an N-terminal signal peptide, two lysine motifs, a transmembrane region, and a serine/threonine kinase domain at the C-terminal end. The expression of HvLysMR1 is induced during exposure to different heavy metals and its transcript accumulates during leaf senescence. Addition of the calcium ionophore A23187 induces HvLysMR1 expression, indicating the involvement of Ca2+ in the regulation of HvLysMR1. In vitro phosphorylation of HvLysMR1 was analysed with [32P]ATP. Using the overexpressed and purified HvLysMR1-kinase domain, the phosphorylation of HvLysMR1 could be confirmed by nano-liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) with neutral loss-triggered MS-MS-MS spectra at amino acids localized at the juxtamembrane region. The involvement of HvLysMR1 during heavy metal stress and leaf senescence is discussed.
authors.affiliation: Martin-Luther Universität Halle-Wittenberg, Institut für Biologie, Weinbergweg 10, D-06120 Halle, Germany.
authors.forename: Akli
authors.initials: A
authors.lastname: Ouelhadj
authors.forename: Marc
authors.initials: M
authors.lastname: Kaminski
authors.forename: Maria
authors.initials: M
authors.lastname: Mittag
authors.forename: Klaus
authors.initials: K
authors.lastname: Humbeck
mesh_terms: D000375:Aging; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000494:pharmacology; D002734:Chlorophyll / Q000378:metabolism; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D004790:Enzyme Induction / Q000187:drug effects; D001467:Hordeum / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*; D019216:Metals, Heavy / Q000633:toxicity*; D045331:Photosystem I Protein Complex / Q000378:metabolism; D018515:Plant Leaves / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development; D010940:Plant Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D011494:Protein Kinases / Q000096:biosynthesis / Q000235:genetics*; D017346:Protein Serine-Threonine Kinases / Q000096:biosynthesis / Q000235:genetics*; D011956:Receptors, Cell Surface / Q000096:biosynthesis / Q000235:genetics*; D015398:Signal Transduction
chemical_list: D018076:DNA, Complementary; D019216:Metals, Heavy; D045331:Photosystem I Protein Complex; D010940:Plant Proteins; D011956:Receptors, Cell Surface; D002734:Chlorophyll; D000001:Calcimycin; D011494:Protein Kinases; C523268:HvLysMR1 protein, Hordeum vulgare; D017346:Protein Serine-Threonine Kinases; D002118:Calcium