Isolation of lambda and YAC clones from defined regions of the rye genome

Abstract

A dispersed, rye-specific element has been used to isolate clones of rye origin from wheat plants containing only a single rye chromosome arm or segment. In this way a set of 23 YAC clones has been isolated from the short arm of rye chromosome 1 (1RS). This technique was extended to isolate clones from a small region of 1RS that contains a large number of agronomically important genes. The targeted cloning method allowed the isolation of 26 classes of lambda clones representing about 5% of the region. Ten of the lambda clones could be mapped to segments within this region. A third example of the application of this technique involved the isolation of clones from a very small but fully functional rye chromosome, the midget chromosome. These clones have allowed the confirmation of the origin of the midget from 1RL, and may provide a tool for the isolation of structural elements of cereal chromosomes. This technique allows the identification of clone libraries for any rye chromosome or chromosome arm, since substitution, addition and translocation lines are available for all rye chromosomes. Furthermore, the technique allows isolation of clones derived from segments of the rye genome recombined into wheat. The method is technically simple and both lambda and YAC libraries can be constructed. Synteny between the genomes of the cereals allows region-specific libraries from rye to be used to target regions of the wheat and barley genomes.

Terminal Regions of Wheat Chromosomes Select Their Pairing Partners in Meiosis

“…These centromere introgressions were produced by recurrent centric breakage-fusion events (Lukaszewski 1993;Zhang et al 2001). Rye centromeres contain species-specific repeats that can be identified by FISH with probe pAWRC.1 when in a wheat background (Langridge et al 1998;Franki 2001). We find that homologous centromeres are mainly separate in presynaptic stages and that the transition to homologous association is driven by synapsis.…”

“…Squashed preparations were C-banded as previously described (Giráldez et al 1979) or subject to FISH with pAWRC.1 containing a rye-specific centromere repeat (Langridge et al 1998;Franki 2001) for identification of marked chromosomes. Observations were under a Nikon Eclipse E400 microscope or Zeiss Axioscope 20.…”

A Cytological Map of the Short Arm of Rye Chromosome 1R Constructed with 1R Dissection Stocks of Common Wheat and PCR-Based Markers

“…We surveyed 139 PCR markers that were reported to be located on 1RS [Guidet et al, 1991;Shimizu et al, 1997;Langridge et al, 1998;Saal and Wricke, 1999;Mago et al, 2002Mago et al, , 2005Bartoš et al, 2008;Kofler et al, 2008;Tsuchida et al, 2008]. We examined 119 microsatellite markers reported by Kofler et al [2008] and chose 13 markers showing clear differential bands by agarose gel electrophoresis.…”

The positioning of rye homologous chromosomes added to wheat through the cell cycle in somatic cells untreated and treated with colchicine

“…Spread preparations of tapetal cells of the anther were hybridized with both, the fluorescein-labelled rye genomic DNA probe and the ryespecific centromere pAWRC1 DNA probe (Langridge et al, 1998;Francki, 2001) labelled by nick-translation with biotin and detected with avidine-Cy3 according to Maestra et al (2002). Images of cells were viewed under an Olympus BX60 fluorescence microscope equipped with an Olympus DP50 CCD camera.…”