title: Linkage mapping and nucleotide polymorphisms of the 6-SFT gene of cool-season grasses.
abstract: Fructan plays an important role as an alternate carbohydrate and may contribute to drought and cold-stress tolerances in various plant species. The gene coding for sucrose:fructan 6-fructosyltransferase (6-SFT; EC 2.4.1.10), an enzyme that catalyzes the formation and extension of beta-2,6-linked fructans (levans), is important to fructan synthesis in many cool-season grasses, including cereal species. In this study, we compared a conserved sequence from the 6-SFT gene in barley with comparable sequences in 20 other cool-season grasses. We detected several DNA length polymorphisms, including variations in one simple-sequence repeat (SSR) in a 6-SFT intron of the barley cultivars Steptoe and Morex. Using the 'Steptoe' x 'Morex' doubled-haploid mapping population, the 6-SFT gene was genetically mapped to the distal region in the short arm of barley chromosome 1 (7H), where it is closely linked with trait locus Rpg1. Primers designed from other conserved regions of the barley 6-SFT gene successfully amplified 351- or 354-bp sequences of this gene from diverse cool season grass species. Sequence identities of the PCR products were greater than 80% among the 21 species. Phylogeny, as determined using these DNA sequences, is similar to that obtained from rDNA ITS sequences, and congruent with our current knowledge of genome relationships.
authors.affiliation: US Department of Agriculture, Utah State University, Logan 84322-6300, USA.
authors.forename: J Z
authors.initials: JZ
authors.lastname: Wei
authors.forename: N J
authors.initials: NJ
authors.lastname: Chatterton
authors.forename: S R
authors.initials: SR
authors.lastname: Larson
authors.forename: R R
authors.initials: RR
authors.lastname: Wang
mesh_terms: D001483:Base Sequence; D002874:Chromosome Mapping; D002875:Chromosomes; D018744:DNA, Plant / Q000032:analysis; D018745:Genome, Plant; D006602:Hexosyltransferases / Q000145:classification / Q000235:genetics*; D001467:Hordeum / Q000235:genetics*; D008969:Molecular Sequence Data; D011110:Polymorphism, Genetic; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid
chemical_list: D018744:DNA, Plant; D006602:Hexosyltransferases; C097181:sucrose - fructan 6-fructosyltransferase