Vitis vinifera terpenoid cyclases: functional identification of two sesquiterpene synthase cDNAs encoding (+)-valencene synthase and (-)-germacrene D synthase and expression of mono- and sesquiterpene synthases in grapevine flowers and berries.
Valencene is a volatile sesquiterpene emitted from flowers of grapevine, Vitis vinifera L. A full-length cDNA from the cultivar Gewürztraminer was functionally expressed in Escherichia coli and found to encode valencene synthase (VvVal). The two major products formed by recombinant VvVal enzyme activity with farnesyl diphosphate (FPP) as substrate are (+)-valencene and (-)-7-epi-alpha-selinene. Grapevine valencene synthase is closely related to a second sesquiterpene synthase from this species, (-)-germacrene D synthase (VvGerD). VvVal and VvGerD cDNA probes revealed strong signals in Northern hybridizations with RNA isolated from grapevine flower buds. Transcript levels were lower in open pre-anthesis flowers, flowers after anthesis, or at early onset of fruit development. Similar results were obtained using a third probe, (-)-alpha-terpineol synthase, a monoterpenol synthase. Sesquiterpene synthase and monoterpene synthase transcripts were not detected in the mesocarp and exocarp during early stages of fruit development, but transcripts hybridizing with VvVal appeared during late ripening of the berries. Sesquiterpene synthase transcripts were also detected in young seeds.
Biotechnology Laboratory, Department of Botany, University of British Columbia, 6174 University Boulevard, Vancouver, BC, V6T 1Z3, Canada.
Joost
J
Lücker
Pat
P
Bowen
Jörg
J
Bohlmann
D019883:Alkyl and Aryl Transferases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D000595:Amino Acid Sequence; D019755:Carbon-Carbon Lyases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D018076:DNA, Complementary / Q000235:genetics; D035264:Flowers / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D005638:Fruit / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D008401:Gas Chromatography-Mass Spectrometry; D018506:Gene Expression Regulation, Plant; D008969:Molecular Sequence Data; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D013729:Terpenes / Q000737:chemistry / Q000378:metabolism*; D014158:Transcription, Genetic / Q000235:genetics; D027843:Vitis / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development
D018076:DNA, Complementary; D010940:Plant Proteins; D018749:RNA, Plant; D013729:Terpenes; D019883:Alkyl and Aryl Transferases; C470416:germacrene D synthase; D019755:Carbon-Carbon Lyases; C051130:trichodiene synthetase