Chromosomal location and genetic mapping of the mismatch repair gene homologs MSH2, MSH3, and MSH6 in rye and wheat
The efficiency of homeologous recombination is influenced by mismatch repair genes in bacteria, yeast, and mammals. To elucidate a possible role of these genes in homeologous pairing and cross-compatibility in plants, gene probes of wheat (Triticum aestivum) specific for the mismatch repair gene homologues MSH2, MSH3, and MSH6 were used to map them to their genomic positions in rye (Secale cereale). Whereas MSH2 was mapped to the short arm of chromosome 1R, MSH3 was mapped to the long arm of chromosome 2R and MSH6 to the long arm of chromosome 5R. Southern blots with nullisomic-tetrasomic (NT) lines of wheat indicated the presence of the sequences on the respective homeologous group of wheat chromosomes. Additionally, an MSH6-specific homologue could also be detected on homoeologous group 3 of wheat. However, in the well-known, highly homoeologous pairing wheat mutant ph1b the MSH6-specific sequence is not within the deleted part of chromosome 5BL, indicating that the pairing phenotype is not due to a loss of one of the mismatch repair genes tested.
Korzun
V
Institut fur Pflanzengenetik und Kulturpflanzenforschung, Gatersleben, Germany. v.korzun@kws.de
Borner
A
Siebert
R
Malyshev
S
Hilpert
M
Kunze
R
Puchta
H