title: Traumatic resin defense in Norway spruce (Picea abies): methyl jasmonate-induced terpene synthase gene expression, and cDNA cloning and functional characterization of (+)-3-carene synthase.
abstract: Picea abies (L.) Karst. (Norway spruce) employs constitutive and induced resin terpenoids as major chemical and physical defense-shields against insects and pathogens. In recent work, we showed that a suite of terpenoids, monoterpenoids and diterpenoids was induced in stems of Norway spruce after treatment of trees with methyl jasmonate (MeJA) (Martin et al., 2002). Increase of enzyme activities of terpenoid biosynthesis and accumulation of terpenoids was associated with MeJA-induced de novo differentiation of xylem resin ducts. The formation of defense-related traumatic resin ducts was also found in Norway spruce after attack by stem boring insects or after infestation with fungal pathogens. In the present study, we analyzed the traumatic resin response in Norway spruce further at the molecular genetic level. Treatment of trees with MeJA induced transient transcript accumulation of monoterpenoid synthases and diterpenoid synthases in stem tissues of Norway spruce. In screening for defense-related terpenoid synthase (TPS) genes from Norway spruce, a full-length monoterpenoid synthase cDNA, PaJF67, was isolated and the recombinant enzyme expressed in E. coli and functionally characterized in vitro. The cloned PaJF67 cDNA represents a new monoterpenoid synthase gene and the gene product was identified as 3-carene synthase. The enzyme encoded by PaJF67 forms stereospecifically (+)-3-carene (78% of total product) together with minor acyclic and cyclic monoterpenes, including the mechanistically closely related terpinolene (11% of total product). (+)-3-Carene is a characteristic monoterpene of constitutive and induced oleoresin defense of Norway spruce and other members of the Pinaceae.
authors.affiliation: Biotechnology Laboratory, Department of Botany and Department of Forest Sciences, University of British Columbia, 6174 University Boulevard, Vancouver V6T 1Z3, BC Canada.
authors.forename: Jenny
authors.initials: J
authors.lastname: Fäldt
authors.forename: Diane
authors.initials: D
authors.lastname: Martin
authors.forename: Barbara
authors.initials: B
authors.lastname: Miller
authors.forename: Suman
authors.initials: S
authors.lastname: Rawat
authors.forename: Jörg
authors.initials: J
authors.lastname: Bohlmann
mesh_terms: D000085:Acetates / Q000494:pharmacology*; D019883:Alkyl and Aryl Transferases / Q000737:chemistry / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D003517:Cyclopentanes / Q000494:pharmacology*; D017931:DNA Primers; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D018506:Gene Expression Regulation, Plant / Q000502:physiology*; D008969:Molecular Sequence Data; D054883:Oxylipins; D010802:Phylogeny; D028222:Picea / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D010937:Plant Growth Regulators / Q000494:pharmacology*; D016133:Polymerase Chain Reaction; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
chemical_list: D000085:Acetates; D003517:Cyclopentanes; D017931:DNA Primers; D054883:Oxylipins; D010937:Plant Growth Regulators; C072239:methyl jasmonate; D019883:Alkyl and Aryl Transferases; C472525:(+)-3-carene synthase, Picea abies; C108877:terpene synthase