Yeasts represent powerful genetic model organisms, due in part to their tiny genomes with very little repetitive DNA. However, one drawback of this feature is an ill-defined metaphase chromosome structure. Fluorescence in situ hybridization has overcome this cytological disadvantage by unequivocally delineating chromosomes and their subregions of interest throughout the cell cycle, irrespective of chromatin compaction. Consequently, chromosome painting and locus-specific yeast FISH are now indispensable tools in the analysis of chromosome organization and dynamics in wild-type and mutant yeast strains. In this chapter, protocols are described that allow nuclei and meiotic chromosomes suitable for FISH analysis to be prepared.
