Monitoring Changes in the Subcellular Location of Proteins in S. cerevisiae

Immunofluorescence (IF) microscopy is indisputably a key tool to study the location of proteins and to visualize intracellular structures in immobilized cells and in spread nuclei. In yeasts, much has been learned using fluorescent tags as labels employing the original methods described, which continue to be quite valuable (1 ). Fixation and staining of whole cells allows for visualization of the subcellular distribution of the protein of interest relative to the phase of the cell cycle. Spreading and staining yeast nuclei are useful steps to determine subnuclear distribution of chromatin-associated proteins and to detect changes in chromosome morphology through the cell cycle. Overtime, these methods have been optimized to promote the preservation of cellular or nuclear structures and/or the antigen of interest, the visualization, or the blocking of nonspecific staining.