Characterisation of type-I thionin loci from the A, B, D and R genomes of wheat and rye
Van Campenhout, Steven × Sagi, Laszlo Vander Stappen, Jacqueline Volckaert, Guido #
Theoretical and applied genetics vol:96 issue:1 pages:80-86
DNA sequences encoding type-I thionins were isolated from Triticum aestivum L. cv 'Chinese Spring' using PCR with consensus primers. Blunt-end cloning. sequencing and PCR-based chromosome assignment of these fragments uncovered the three orthologous sequences corresponding to the single-copy genes at the Pur-1 loci on each of the group-1 chromosomes. Comparison with two previously published cDNA sequences revealed the presence of two introns that contain most of the polymorphic nucleotide sites. The observed orthologous DNA sequence variation among Pur-1 loci, encoded by each of the A, B and D genomes, enabled us to establish interlocus relationships and to construct locus-specific primer sets. Analogously, the Pur-R1 sequence from rye was isolated. and a locus-specific primer pair was constructed as well. Hence. four locus-specific primer sets are now available as molecular markers for the homoeologous 1AL, 1BL, 1DL and 1RL chromosome arms. Amplification from several diploid and tetraploid wheat species showed that the primers can be used as molecular tools for studying wheat phylogeny.