Genetics, physiology and cytology of yeast-mycelial dimorphism in fission yeasts

The orderSchizosaccharomycetalescontains a dimorphic and two yeast species.Sch. japonicuscan form both yeast cells and mycelium, depending on the substrate and the culturing conditions.Sch. pombeis a strictly unicellular organism, but it can be forced to form mycelial cell chains by inactivating members of thesepgene family. The mutations in most of thesepgenes confer pleitropic phenotypes indicating functional involvement in MAP-kinase-mediated signalling pathways. Two of them were found to encode transcription factor homologues of other eukaryotes.