title: Expression of the viviparous 1 (Pavp1) and p34cdc2 protein kinase (cdc2Pa) genes during somatic embryogenesis in Norway spruce (Picea abies [L.] Karst).
abstract: Detailed expression analysis of the Norway spruce (Picea abies [L.] Karst) Viviparous 1 (Pavp1) and p34cdc2 (cdc2Pa) genes was carried out during somatic embryogenesis. Pavp1, a gene associated with embryo development, was expressed in proliferating embryogenic suspension cultures in the absence of exogenous ABA. When somatic embryo formation was promoting by blocking proliferation, Pavp1 expression was reduced. During maturation, exogenous ABA induced increased Pavp1 expression, which peaked at the early cotyledonary stage of somatic embryogenesis. Following partial desiccation of mature somatic embryos at high relative humidity, Pavp1 expression persisted under germination conditions. Pavp1 expression was also detected in non-dormant immature male strobili and dormant terminal buds. These data confirm the functional conservation of Pavp1 during the evolution of seed plants and extend its function beyond the embryo. Cdc2Pa, a gene associated with the cell cycle, was up-regulated when the proliferation of embryogenic cells was blocked. Expression was again up-regulated in early embryogeny and again during germination. The implications of this up-regulation of cdc2Pa are discussed.
authors.affiliation: Department of Plant Biology and Forest Genetics, Uppsala Genetic Centre, Swedish University of Agricultural Sciences, Box 7027, Uppsala 750-07, Sweden.
authors.forename: Steven
authors.initials: S
authors.lastname: Footitt
authors.forename: Mathieu
authors.initials: M
authors.lastname: Ingouff
authors.forename: David
authors.initials: D
authors.lastname: Clapham
authors.forename: Sara
authors.initials: S
authors.lastname: von Arnold
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D000595:Amino Acid Sequence; D016203:CDC2 Protein Kinase / Q000235:genetics* / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018525:Germination / Q000502:physiology; D008969:Molecular Sequence Data; D028222:Picea / Q000196:embryology / Q000235:genetics* / Q000254:growth & development; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D012639:Seeds / Q000196:embryology / Q000235:genetics* / Q000254:growth & development; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity; D015534:Trans-Activators; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; D010940:Plant Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D000040:Abscisic Acid; D016203:CDC2 Protein Kinase