Bancroft I.,John Innes Center |
Morgan C.,John Innes Center |
Fraser F.,John Innes Center |
Higgins J.,John Innes Center |
And 10 more authors.
Polyploidy complicates genomics-based breeding of many crops, including wheat, potato, cotton, oat and sugarcane. To address this challenge, we sequenced leaf transcriptomes across a mapping population of the polyploid crop oilseed rape (Brassica napus) and representative ancestors of the parents of the population. Analysis of sequence variation 1 and transcript abundance enabled us to construct twin single nucleotide polymorphism linkage maps of B. napus, comprising 23,037 markers. We used these to align the B. napus genome with that of a related species, Arabidopsis thaliana, and to genome sequence assemblies of its progenitor species, Brassica rapa and Brassica oleracea. We also developed methods to detect genome rearrangements and track inheritance of genomic segments, including the outcome of an interspecific cross. By revealing the genetic consequences of breeding, cost-effective, high-resolution dissection of crop genomes by transcriptome sequencing will increase the efficiency of predictive breeding even in the absence of a complete genome sequence. © 2011 Nature America, Inc. All rights reserved. Source
Wang H.,Key Laboratory of Horticultural Crop Genetic Improvement |
Wang H.,Sino Dutch Joint Laboratory of Horticultural Genomics Technology |
Wang H.,Chinese Academy of Agricultural Sciences |
Wu J.,Key Laboratory of Horticultural Crop Genetic Improvement |
And 17 more authors.
Glucosinolates (GS) are a group of amino acid-derived secondary metabolites found throughout the Cruciferae family. Glucosinolates and their degradation products play important roles in pathogen and insect interactions, as well as in human health. In order to elucidate the glucosinolate biosynthetic pathway in Brassica rapa, we conducted comparative genomic analyses of Arabidopsis thaliana and B. rapa on a genome-wide level. We identified 102 putative genes in B. rapa as the orthologs of 52 GS genes in A. thaliana. All but one gene was successfully mapped on 10 chromosomes. Most GS genes exist in more than one copy in B. rapa. A high co-linearity in the glucosinolate biosynthetic pathway between A. thaliana and B. rapa was also established. The homologous GS genes in B. rapa and A. thaliana share 59-91% nucleotide sequence identity and 93% of the GS genes exhibit synteny between B. rapa and A. thaliana. Moreover, the structure and arrangement of the B. rapa GS (BrGS) genes correspond with the known evolutionary divergence of B. rapa, and may help explain the profiles and accumulation of GS in B. rapa. © 2011 Elsevier B.V. Source