Submitted to: Journal of Theoretical and Applied Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/28/2002
Publication Date: 2/3/2003
Citation: YAN, H., MUDGE, J., KIM, D., SHOEMAKER, R.C., COOK, D. ESTIMATES OF CONSERVED MICROSYNTENY AMONG THE GENOMES OF SOYBEAN, MEDICAGO TRUNCATULA, AND ARABIDOPSIS THALIANA. JOURNAL OF THEORETICAL AND APPLIED GENETICS. 2003. v. 106. p. 1256-1265. Interpretive Summary: New technologies are allowing the collection of information about genetic inheritance of important genes at a faster and faster rate. The ability to transfer this information from one species to another would ensure that time and money are saved. It would also reduce redundancy in research efforts. The authors used some of these new technologies to determine how much information might be transferred from one legume to another, soybean. They found that about 38% of the time, regions of the soybean chromosomes were very similar to regions of the chromosomes of the other plant. This means that molecular genetic information gained from the other legume should be immediately transferred to soybean. This should result in information gathering for soybean, an important agricultural crop, can occur much faster and cheaper than previously thought.
Technical Abstract: A hybridization-based approach was used to estimate genome-wide conserved microsynteny between the genomes of Medicago truncatula (Mt) and Glycine max (soybean). A total of 187 soybean bacterial artificial chromosome (BAC) subclones and restriction fragment length polymorphism (RFLP) probes plus 106 whole BAC clones from contigs of known map position were used in cross-hybridization experiments with a Mt BAC library. Restriction fragment analysis and Southern blot hybridization confirmed that these probes did not contain Mt repetitive DNA. Limited microsynteny was inferred when at least two probes (sequences) from a soybean contig hybridized to a common Mt BAC; extensive microsynteny was inferred when a whole soybean BAC clone hybridized to five or more fragments from a Mt BAC. Of the 50 soybean contig groups examined, 54% showed conserved microsynteny to the Mt genome, including 38% with extensive and 16% with limited conserved microsynteny. In a similar strategy, the degree of conservation among soybean homoeologues was also investigated. The results indicated substantial conservation among soybean homoeologues, with 67.6% showing extensive and 29.7% showing limited conserved microsynteny. We suggest that at least two rounds of large-scale duplications have occured in the soybean lineage. A sequence-based homology search was also performed between the 50 soybean contig groups and the Arabidopsis genome. Depending upon the stringency level, between 6% and 12% of the soybean contig groups exhibited conserved microsynteny with Arabidopsis.