Schizosaccharomyces Pombe - Life Cycle

Life Cycle

The fission yeast is a single-celled fungus with simple, fully characterized genome and a rapid growth rate. It has long since been used in brewing, baking and molecular genetics. S. pombe is a rod-shaped cell, approximately 3 µm in diameter, that grows entirely by elongation at the ends. After mitosis, division occurs by the formation of a septum, or cell plate, that cleaves the cell at its midpoint.

The central events of cell reproduction are chromosome duplication, which takes place in S (Synthetic) phase, followed by chromosome segregation and nuclear division (mitosis) and cell division (cytokinesis), which are collectively called M (Mitotic) phase.G1 is the gap between M and S phases, and G2 is the gap between S and M phases. In the budding yeast, the G2 phase is particularly extended, and cytokinesis (daughter-cell segregation) does not happen until a new S (Synthetic) phase is launched.

Fission yeast governs mitosis by mechanisms that are similar to those in multicellular animals. It normally proliferates in a haploid state. When starved, cells of opposite mating types (P and M) fuse to form a diploid zygote that immediately enters meiosis to generate four haploid spores. When conditions improve, these spores germinate to produce proliferating haploid cells.

• General features of the cell cycle.

• The particular cell cycle of a fission yeast.

• A more detailed version of the cell cycle of a fission yeast.