Together with Lee Hartwell and Tim Hunt, Nurse won the 2001 Nobel Prize in Physiology or Medicine for work on cell cycle regulation.

Schizosaccharomyces pombe was first discovered in 1893 when a group working in a Brewery Association Laboratory in Germany was looking at sediment found in millet beer imported from East Africa that gave it an acidic taste.

The standard S. pombe strains were isolated by Urs Leupold in 1946 and 1947 from a culture that he obtained from the yeast collection in Delft, The Netherlands.

liquefaciens, after he isolated it in 1924 from French wine (most probably rancid) at the Federal Experimental Station of Vini- and Horticulture in Wädenswil, Switzerland.

[14] The fission yeast S. pombe belongs to the division Ascomycota, which represents the largest and most diverse group of fungi.

Free-living ascomycetes are commonly found in tree exudates, on plant roots and in surrounding soil, on ripe and rotting fruits, and in association with insect vectors that transport them between substrates.

Some of the technical discriminants between these two species are: S. pombe gene products (proteins and RNAs) participate in many cellular processes common across all life.

The fission yeast GO slim provides a categorical high level overview of the biological role of all S. pombe gene products.

[8] The fission yeast is a single-celled fungus with simple, fully characterized genome and a rapid growth rate.

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.

The anaphase spindle (in green on the figure) is then positioned so that the segregated chromosomes are on opposite sides of the predetermined cleavage plane.

In fission yeast, where growth governs progression through G2/M, a wee1 mutation causes entry into mitosis at an abnormally small size, resulting in a shorter G2.

Fission yeast switches mating type by a replication-coupled recombination event, which takes place during S phase of the cell cycle.

In addition, work on the silenced donor region has led to great advances in understanding formation and maintenance of heterochromatin.

[26] Supporting this view is the finding that single base lesions of the type dU:dG in the DNA of S. pombe stimulate meiotic recombination.

[27] This recombination requires uracil-DNA glycosylase, an enzyme that removes uracil from the DNA backbone and initiates base excision repair.

[28] Fission yeast has become a notable model system to study basic principles of a cell that can be used to understand more complex organisms like mammals and in particular humans.

[32][25][30][37][38] Schizosaccharomyces pombe is often used to study cell division and growth because of conserved genomic regions also seen in humans including: heterochromatin proteins, large origins of replication, large centromeres, conserved cellular checkpoints, telomere function, gene splicing, and many other cellular processes.

Structural and functional analysis of these gene regions can be found on large scale fission yeast databases such as PomBase.

This elongation of centromeres and its conservative sequences makes fission yeast a practical model system to use to observe cell division and in humans because of their likeness.

[47] Biodiversity and evolutionary study of fission yeast was carried out on 161 strains of Schizosaccharomyces pombe collected from 20 countries.

[48] Modeling of the evolutionary rate showed that all strains derived from a common ancestor that has lived since ~2,300 years ago.

[40][50][51][52] Other stages, such as cellular growth and aging, are also observed in yeast in order to understand these mechanisms in more complex systems.

[34][53][54][55] S. pombe stationary phase cells undergo chronological aging due to production of reactive oxygen species that cause DNA damages.

Well-conserved components of cytokinesis are observed in fission yeast and allow us to look at various genomic scenarios and pinpoint mutations.

[64][65] Mitochondria diseases, and various organelle systems such as the Golgi apparatus and endoplasmic reticulum, can be further understood, by observing fission yeast's chromosome dynamics and protein expression levels and regulation.

"The MDR response involves overexpression of two types of drug efflux pumps, the ATP-binding cassette (ABC) family... and the major facilitator superfamily".

Researchers are looking for ways to further understand how doxorubicin works by observing the genes linked to resistance by using fission yeast as a model system.

[32] This process is easily visible and observable under any microscope and allows us to look at meiosis in a simpler model system to see how this phenomenon operates.

Making knock-in and knock-out genes is fairly easy and with the fission yeast's genome being sequenced this task is very accessible and well known.