title: Characterization of a type-A response regulator differentially expressed during adventitious caulogenesis in Pinus pinaster.
abstract: The molecular cloning and characterization of PipsRR1, a type-A response regulator in Pinus pinaster, is reported here. Type-A response regulators mediate downstream responses to cytokinin and act as negative feedback regulators of the signal transduction pathway. Some type-A response regulators in Arabidopsis have been related to de novo meristem formation. However, little information exists in Pinus spp. The PipsRR1 gene contains 5 exons, as do all type-A response regulators in Arabidopsis, and the deduced protein contains a receiver domain with the conserved DDK residues and a short C terminal extension. Expression analysis showed that the PipsRR1 gene is differentially expressed during the first phases of adventitious caulogenesis induced by benzyladenine in P. pinaster cotyledons, suggesting that PipsRR1 plays a role in caulogenesis in conifers. Additionally, a binary vector carrying the PipsRR1 promoter driving GFP:GUS expression was constructed to analyze the promoter activity in P. pinaster somatic embryos. The results of genetic transformation showed GUS activity during somatic embryo mass proliferation and embryo maturation.
authors.affiliation: Laboratorio de Biotecnología Agroforestal, Escuela Politécnica de Mieres, Universidad de Oviedo, C/Gonzalo Gutiérrez Quirós, 33600 Mieres, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Alvarez
authors.forename: Millán
authors.initials: M
authors.lastname: Cortizo
authors.forename: Ricardo J
authors.initials: RJ
authors.lastname: Ordás
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D001555:Benzene Derivatives / Q000494:pharmacology*; D002874:Chromosome Mapping; D018548:Cotyledon / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D003583:Cytokinins / Q000378:metabolism*; D018744:DNA, Plant / Q000737:chemistry / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter; D008969:Molecular Sequence Data; D028223:Pinus / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development / Q000502:physiology; D010937:Plant Growth Regulators / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D018520:Plant Shoots / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000502:physiology; D058439:Plant Somatic Embryogenesis Techniques; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic / Q000235:genetics; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D015398:Signal Transduction; D014170:Transformation, Genetic
chemical_list: D001555:Benzene Derivatives; D003583:Cytokinins; D018744:DNA, Plant; D010937:Plant Growth Regulators; D010940:Plant Proteins