The aniline blue fluorochrome specifically stains the septum of both live and fixed Schizosaccharomyces pombe cells

Abstract A novel method is described which uses aniline blue for the specific fluorescent staining of the septa of dividing cells of the fission yeast, Schizosaccharomvces pombe . It gives the same results with live and fixed cells. In fixed or, more generally, dead cells there is no staining of the cytoplasm: this renders aniline blue superior to other dyes previously used to stain the septum of S. pombe . This feature allows quantitative analysis of the septum index for fixed samples and, therefore, makes aniline blue the stain of choice for cell cycle kinetic studies.