Slime Moulds

Abstract

Abstract Slime moulds are organisms that feed and grow like protozoa but reproduce like fungi. No single taxonomic group encompasses all slime moulds. Instead, the slime mould habit has arisen multiple times across a number of different groups. Their unusual name belies the importance of some species as experimental research organisms. The cellular slime mould Dictyostelium discoideum has provided significant insights into cell differentiation and pattern formation, cell motility, cell signalling, gene expression and cell adhesion and in recent years has also been employed in studies of the mechanism of action of pharmaceuticals, the cellular effects of pathogenic microorganisms and the evolution of social behaviour. The plasmodial slime mould Physarum polycephalum has provided insights into cytoplasmic streaming and control of nuclear division and more recently has been employed in practical and theoretical studies of path finding. The comparative genomics of the multicellular slime moulds has the potential to provide insights into the evolution of multicellularity. Key Concepts ‘Slime moulds’ is a descriptive term rather than a systematic category. The slime mould habit of protozoan‐like feeding stages alternating with fungus‐like reproductive stages has arisen independently in a wide variety of microorganisms embracing three of the major supergroups of Eukaryotes. The multicellular slime moulds include the well‐known social amoeba Dictyostelium discoideum , which has had broad application as a model research organism in the study of fundamental cellular processes. The plasmodial slime moulds include Physarum polycephalum , which has been used as a model for studying fundamental cellular processes and has recently been used by physicists and computer scientists for network analysis and other studies. Complete genome sequences are available for many of the multicellular slime moulds and their nonaggregative and nonfruiting amoebal relatives. This presents intriguing prospects for exploring the evolution of multicellularity using comparative genomics.