Plant & Animal Genomes XIII Conference

January 15-19, 2005
Town & Country Convention Center
San Diego, CA

Conservation Of Synteny Between Pea And Lentil With Extrapolation To Medicago, Lotus And Arabidopsis

Norman F. Weeden¹ , Jason G. Walling² , Matt Moffet¹

¹  Montana State University, Bozeman, MT 59717 USA

²  Purdue University, West Lafayette, IN 47907 USA

Pea and lentil both have a haploid complement of 7 chromosomes and both are assigned to the tribe Vicieae within the Fabaceae. This close phylogenic relationship suggests that the linkage maps for the two species should display considerable conservation of synteny. We have compared the positions of over 100 sequence-tagged genes on each of the linkage maps. The results reveal many regions where gene arrangement has been conserved, although it appears that every linkage groups shows rearrangement either within Pisum or between Pisum and Lens. Comparisons of gene arrangement in the Viceae with that in Medicago truncatula indicate a level of chromosomal rearrangement slightly greater than that between pea and lentil. The positions of the 5S RNA and 45S RNA coding sequences appear particularly susceptible to rearrangement. Conservation of gene arrangement, or at least linkage, over short distances (<10 cM) appears to be common among a range of temperate legumes. Conservation of linkage between the Viceae or Trifolieae and the more distant Phaseoleae or Glycineae is much more limited. However, several cases of linkage conservation between pea or M. truncatula and Arabidopsis have been identified. Although these regions are very small (<200 kb in Arabidopsis), their presence suggests that comparative genomics will useful throughout the Fabaceae for gene isolation via marker-based cloning.