Controlling septation in fission yeast: finding the middle, and timing it right

The fission yeast Schizosaccharomyces pombe provides a simple eukaryotic mo del for the study of cytokinesis. S. pombe cells are rod-shaped, grow mainl y by elongation at their tips, and divide by binary fission after forming a centrally placed division septum. Analysis of mutants has begun to shed li ght upon how septum formation and cytokinesis are regulated both spatially and temporally. Some of the proteins involved in these events have been fun ctionally conserved throughout eukaryotic evolution, suggesting that aspect s of this control will be common to all eukaryotic cells.