Comparison of Schizosaccharomyces pombe expression systems

Analysis of a variety of problems in yeast relies on ectopic expression of the protein of interest under control of a heterologous promoter. In the fission yeast S. pombe , there are relatively few expression plasmids and most reports of their activity have not been comparative. It is thus difficult to determine the comparability of experiments carried out using different expression vectors. When new promoters are characterised, it is likewise difficult to determine their activity relative to those previously identified. In order to better assess relative promoter strengths, I have compared the activity of several inducible and constitutive expression systems in fission yeast by using a beta-galactosidase reporter gene. This allows a more informed choice of appropriate expression systems for analysis of gene function in S. pombe .