An Ancient Yeast for Young Geneticists: A Primer on the Schizosaccharomyces pombe Model System

Abstract

The fission yeast Schizosaccharomyces pombe is an important model organism for the study of eukaryotic molecular and cellular biology. Studies of S. pombe, together with studies of its distant cousin, Saccharomyces cerevisiae, have led to the discovery of genes involved in fundamental mechanisms of transcription, translation, DNA replication, cell cycle control, and signal transduction, to name but a few processes. However, since the divergence of the two species approximately 350 million years ago, S. pombe appears to have evolved less rapidly than S. cerevisiae so that it retains more characteristics of the common ancient yeast ancestor, causing it to share more features with metazoan cells. This Primer introduces S. pombe by describing the yeast itself, providing a brief description of the origins of fission yeast research, and illustrating some genetic and bioinformatics tools used to study protein function in fission yeast. In addition, a section on some key differences between S. pombe and S. cerevisiae is included for readers with some familiarity with budding yeast research but who may have an interest in developing research projects using S. pombe.

Keywords: Model Organism Database; Primer; Saccharomyces cerevisiae; Schizosaccharomyces pombe; education; fission yeast; forward genetics; genetic screen; model system.

Figure 1

S.pombe publication numbers from 1959 to 2014.

Figure 2

S. pombe cells and asci. (A) A haploid cell containing a fission plate. (B) Diploid cells. (C) Zygotic asci formed by the mating of two haploid cells. (D) Azygotic asci formed when diploid cells go through meiosis.

Figure 3

Sexual development in S. pombe. Cells of the homothallic h⁹⁰ mating type were plated onto a thin EMM agar pad at 30° and photographed at (A) 0 min, (B) 184 min, (C) 204 min, (D) 254 min, (E) 286 min, (F) 334 min, (G) 446 min, and (H) 560 min. Because h⁹⁰ cells can undergo mating-type switching, which occurs in only one of the two daughter cells, two pairs of daughter are seen to have mated and formed asci.

Figure 4

Schematic of the S. pombe mating-type locus.

Figure 5

Outline for genetic analysis of nudA gene.

Figure 6

Gap-repair cloning of the nudA gene. The nudA gene is amplified by PCR using oligonucleotides that target its insertion into the linearized expression vector pART1 by gap repair transformation. This places the nudA open reading frame under the control of the S. pombe adh1 promoter to drive its expression in fission yeast.