title: Molecular characterization of maize bHLH transcription factor (ZmKS), a new ZmOST1 kinase substrate.
abstract: In order to identify potential substrates of the maize kinase in the ABA signalling network, ZmOST1 was used as bait against a library of cDNAs from dehydrated young leaves. A ZmOST1-interactive polypeptide ZmKS (gene locus tag: GRMZM2G114873), showing homology with the Arabidopsis thaliana basic helix-loop-helix (bHLH) DNA-binding transcription factor was identified. Using a comparative genomic approach, the ZmKS corresponding protein was identified as conceptual translated bHLH transcription factor ABA-responsive kinase substrate. ZmKS is localized in the nucleus, shows a potential binding specificity preferentially detectable on cis-acting E-box like heptameric motifs CCACTTG and CAAGTTG, and is phosphorylated by maize protein kinase ZmOST1. ZmKS is expressed in embryo, leaf and root, expression being affected by ABA and osmotic stress. Transgenic Arabidopsis plants, with gain of ZmKS function, show a delay in germination and a transcriptional stomatal opening-facilitator activity, switchover upon ZmKS phosphorylation, suggesting that ZmKS is an ABA-repressed trans-acting activator.
authors.affiliation: Centre de Recerca en Agrigenòmica 20 (CRAG), Consortium CSIC-IRTA-UAB-UB. Campus UAB - Edifici CRAG, 21 Cerdanyola del Vallès, 08193 Barcelona, Spain.
authors.forename: Agnese
authors.initials: A
authors.lastname: Rabissi
authors.affiliation: Centre de Recerca en Agrigenòmica 20 (CRAG), Consortium CSIC-IRTA-UAB-UB. Campus UAB - Edifici CRAG, 21 Cerdanyola del Vallès, 08193 Barcelona, Spain.
authors.forename: Belmiro
authors.initials: B
authors.lastname: Vilela
authors.affiliation: Centre de Recerca en Agrigenòmica 20 (CRAG), Consortium CSIC-IRTA-UAB-UB. Campus UAB - Edifici CRAG, 21 Cerdanyola del Vallès, 08193 Barcelona, Spain.
authors.forename: Victoria
authors.initials: V
authors.lastname: Lumbreras
authors.affiliation: Centre de Recerca en Agrigenòmica 20 (CRAG), Consortium CSIC-IRTA-UAB-UB. Campus UAB - Edifici CRAG, 21 Cerdanyola del Vallès, 08193 Barcelona, Spain.
authors.forename: Dolors
authors.initials: D
authors.lastname: Ludevid
authors.affiliation: Instituto de Biología Molecular y Celular de Plantas, Universidad Politécnica de Valencia-C.S.I.C, Camino de Vera, s/n. 46022, Valencia, Spain. Electronic address: faculia@ibmcp.upv.es.
authors.forename: Francisco A
authors.initials: FA
authors.lastname: Culiáñez-Macià
authors.affiliation: Centre de Recerca en Agrigenòmica 20 (CRAG), Consortium CSIC-IRTA-UAB-UB. Campus UAB - Edifici CRAG, 21 Cerdanyola del Vallès, 08193 Barcelona, Spain.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Pagés
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism*; D000595:Amino Acid Sequence; D017360:Arabidopsis; D051792:Basic Helix-Loop-Helix Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D003313:Zea mays / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics
chemical_list: D000040:Abscisic Acid; D051792:Basic Helix-Loop-Helix Proteins; D010940:Plant Proteins
keywords: ABA-repressed; Abiotic stress; Stomatal activity; Zea mays; bHLH transcription factor