Isolation and functional expression of an animal geranyl diphosphate synthase and its role in bark beetle pheromone biosynthesis.
Geranyl diphosphate synthase (GPPS) catalyzes the condensation of dimethylallyl diphosphate and isopentenyl diphosphate to form geranyl diphosphate. Geranyl diphosphate is the precursor of monoterpenes, a large family of natural occurring C(10) compounds predominantly found in plants. Similar to plants but unique to animals, some bark beetle genera (Coleoptera: Scolytidae) produce monoterpenes that function in intraspecific chemical communication as aggregation and dispersion pheromones. The release of monoterpene aggregation pheromone mediates host colonization and mating. It has been debated whether these monoterpene pheromone components are derived de novo through the mevalonate pathway or result from simple modifications of dietary precursors. The data reported here provide conclusive evidence for de novo biosynthesis of monoterpene pheromone components from bark beetles. We describe GPPS in the midgut tissue of pheromone-producing male Ips pini. GPPS expression levels are regulated by juvenile hormone III, similar to other mevalonate pathway genes involved in pheromone biosynthesis. In addition, GPPS transcript is almost exclusively expressed in the anterior midgut of male I. pini, the site of aggregation pheromone biosynthesis. The recombinant enzyme was functionally expressed and produced geranyl diphosphate as its major product. The three-dimensional model structure of GPPS shows that the insect enzyme has the sequence structural motifs common to E-isoprenyl diphosphate synthases.
Gilg
Anna B
AB
Department of Biochemistry and Molecular Biology, University of Nevada, Reno, NV 89557-0014, USA.
Bearfield
Jeremy C
JC
Tittiger
Claus
C
Welch
William H
WH
Blomquist
Gary J
GJ
D019883:Alkyl and Aryl Transferases / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D016000:Cluster Analysis; D001517:Coleoptera / Q000201:enzymology*; D017931:DNA Primers; D004064:Digestive System / Q000378:metabolism; D020869:Gene Expression Profiling; D015971:Gene Expression Regulation, Enzymologic; D008297:Male; D008958:Models, Molecular; D008969:Molecular Sequence Data; D039821:Monoterpenes / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D012717:Sesquiterpenes / Q000378:metabolism; D012724:Sex Attractants / Q000096:biosynthesis*; D014018:Tissue Distribution
D017931:DNA Primers; D039821:Monoterpenes; D012717:Sesquiterpenes; D012724:Sex Attractants; C036585:juvenile hormone III; D019883:Alkyl and Aryl Transferases