title: The family of terpene synthases in plants: a mid-size family of genes for specialized metabolism that is highly diversified throughout the kingdom.
abstract: Some plant terpenes such as sterols and carotenes are part of primary metabolism and found essentially in all plants. However, the majority of the terpenes found in plants are classified as 'secondary' compounds, those chemicals whose synthesis has evolved in plants as a result of selection for increased fitness via better adaptation to the local ecological niche of each species. Thousands of such terpenes have been found in the plant kingdom, but each species is capable of synthesizing only a small fraction of this total. In plants, a family of terpene synthases (TPSs) is responsible for the synthesis of the various terpene molecules from two isomeric 5-carbon precursor 'building blocks', leading to 5-carbon isoprene, 10-carbon monoterpenes, 15-carbon sesquiterpenes and 20-carbon diterpenes. The bryophyte Physcomitrella patens has a single TPS gene, copalyl synthase/kaurene synthase (CPS/KS), encoding a bifunctional enzyme producing ent-kaurene, which is a precursor of gibberellins. The genome of the lycophyte Selaginella moellendorffii contains 18 TPS genes, and the genomes of some model angiosperms and gymnosperms contain 40-152 TPS genes, not all of them functional and most of the functional ones having lost activity in either the CPS- or KS-type domains. TPS genes are generally divided into seven clades, with some plant lineages having a majority of their TPS genes in one or two clades, indicating lineage-specific expansion of specific types of genes. Evolutionary plasticity is evident in the TPS family, with closely related enzymes differing in their product profiles, subcellular localization, or the in planta substrates they use.
authors: Department of Plant Sciences, University of Tennessee, Knoxville, TN 37996, USA. fengc@utk.edu
authors: Feng
authors: F
authors: Chen
authors: Dorothea
authors: D
authors: Tholl
authors: Jörg
authors: J
authors: Bohlmann
authors: Eran
authors: E
authors: Pichersky
mesh_terms: D019883:Alkyl and Aryl Transferases / Q000235:genetics* / Q000378:metabolism; D055028:Comparative Genomic Hybridization; D019143:Evolution, Molecular; D020440:Gene Duplication; D017343:Genes, Plant; D014644:Genetic Variation; D018745:Genome, Plant; D005810:Multigene Family; D010802:Phylogeny; D010944:Plants / Q000201:enzymology* / Q000235:genetics; D013379:Substrate Specificity; D013729:Terpenes / Q000378:metabolism
chemical_list: D013729:Terpenes; D019883:Alkyl and Aryl Transferases; C108877:terpene synthase