Construction of yeast artificial chromosomes containing barley DNA and the identification of clones carrying copies of the repeated element BIS-1.

Yeast artificial chromosome (YAC) cloning vectors allow the isolation and analysis of very large segments of DNA. Barley DNA was cleaved with the rare-cutting restriction enzyme MluI and fractionated according to size on a linear sucrose gradient or by pulsed field gel electrophoresis. DNA fragments of approximately 50-250 kb were ligated with the YAC vector pYAC-RC and transformed into yeast spheroplasts. The presence of recombinant YACs with barley DNA inserts was established, and a number of clones containing copies of the repeated element BIS-1 were isolated. These results show that YAC cloning techniques can be successfully applied to the analysis of the barley genome.