Comparative analyses between lolium/festuca introgression lines and rice reveal the major fraction of functionally annotated gene models is located in recombination-poor/very recombination-poor regions of the genome.
Publication of the rice genome sequence has allowed an in-depth analysis of genome organization in a model monocot plant species. This has provided a powerful tool for genome analysis in large-genome unsequenced agriculturally important monocot species such as wheat, barley, rye, Lolium, etc. Previous data have indicated that the majority of genes in large-genome monocots are located toward the ends of chromosomes in gene-rich regions that undergo high frequencies of recombination. Here we demonstrate that a substantial component of the coding sequences in monocots is localized proximally in regions of very low and even negligible recombination frequencies. The implications of our findings are that during domestication of monocot plant species selection has concentrated on genes located in the terminal regions of chromosomes within areas of high recombination frequency. Thus a large proportion of the genetic variation available for selection of superior plant genotypes has not been exploited. In addition our findings raise the possibility of the evolutionary development of large supergene complexes that confer a selective advantage to the individual.
King
Julie
J
Plant Genetics and Breeding Department, Institute of Grassland and Environmental Research, Aberystwyth, SY23 3EB, United Kingdom. julie.king@bbsrc.ac.uk
Armstead
Ian P
IP
Donnison
S Iain
SI
Roberts
Luned A
LA
Harper
John A
JA
Skøt
Kirsten
K
Elborough
Kieran
K
King
Ian P
IP
D002874:Chromosome Mapping; D003062:Codon / Q000235:genetics; D019143:Evolution, Molecular; D017353:Gene Deletion; D017343:Genes, Plant / Q000235:genetics*; D018745:Genome, Plant; D008129:Lolium / Q000235:genetics*; D008957:Models, Genetic; D012275:Oryza / Q000235:genetics*; D011995:Recombination, Genetic
D003062:Codon