Meiotic cytogenetics in Coprinus cinereus.

The basidiomycete fungus Coprinus cinereus has naturally synchronous meiosis and is amenable to analysis using an array of well-developed genetic and molecular tools. In this chapter, we explain in detail the two methods most commonly employed for C. cinereus, staining of intact gill segments and chromosome spreads, with an example of the application of each. We describe iron-hematoxylin staining of intact gill segments for the brightfield examination of meiotic progression, and the use of surface spreads and fluorescence in situ hybridization (FISH) to investigate meiotic chromosome pairing. Gill segments can alternatively be stained with DAPI for the determination of meiotic stage, or propidium iodide for the quantitation of nuclear DNA content, and the chromosome fixation and spreading techniques used for FISH are also suitable for immunolocalization studies of chromosomal proteins.