Figure 4.

Structure of Wheat Chromosome 4A in Relation to the Barley Genome Zipper.

Wheat subgenome specific markers of chromosome 4A have been compared against the genome zipper chromosome model of barley (for a genome-wide overview, see Supplemental Figure 5 online). Orthologous regions are depicted and visualized by a heatmap.

(A) Wheat EST markers allocated to 4AS cross-match to barley genes on 4HL and markers allocated to 4AS, a small region on 4AL, 5AL, and 7BS cross-match to 4HL. Thus, a reciprocal translocation involving chromosomes 4A and 5A and a translocation from 7BS to 4AL was detected. Compared with barley 4H, wheat chromosome 4A contains a pericentromeric inversion.

(B) The barley genome zipper model allows the size of the affected regions to be estimated and the minimal number of genes located in these rearranged regions of the wheat chromosomes to be predicted.