Submitted to: Journal of Heredity
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/11/2008
Publication Date: 7/1/2008
Citation: Schlueter, J.A., Scheffler, B.E., Jackson, S., Shoemaker, R.C. 2008. Fractionation of Synteny in a Genomic Region Containing Tandemly Duplicated Genes Across Glycine max, Medicago truncatula and Arabidopsis thaliana. Journal of Heredity. Interpretive Summary: In order to take full advantage of genetic advancements in model plants and to transfer information learned in those systems to a crop, it is advantageous to have a conserved gene order in all species. In this report the authors used DNA sequences and bioinformatic approaches to assess how well gene order in model species compares to gene order in soybean. They focused on a region of a soybean chromosome that contains a family of genes possibly related to disease and stress resistance. They found that although some gene order was conserved among species, many genes had been lost or gained, thus yielding a 'shuffled' appearance of the chromosomal region. Surprisingly, they also found that the gene family has most likely been created independently in all three species. This information is important to geneticist who will be attempting to assemble the DNA sequence of the entire soybean genetic complement, and who may wish to rely upon the DNA sequence assembly of the model plants.
Technical Abstract: Extended comparison of gene sequences found on homeologous soybean BACs to Medicago truncatula and Arabidopsis thaliana genomic sequences demonstrated a network of synteny within conserved regions interrupted by gene addition and/or deletions. Consolidation of gene order among all three species provides a picture of ancestral gene order. The observation supports a genome history of fractionation resulting from gene loss/addition and rearrangement. In all three species, clusters of N-hydroxycinnamoyl/benzoyltransferase (HCBT) genes were identified in tandemly duplicated clusters. Parsimony-based gene trees suggests the genes within the arrays have independently undergone tandem duplication in each species.