Evolution of the Mating-Type Locus: The Basidiomycetes

Abstract

Sexual reproduction is ubiquitous in nature. As the engine that drives genetic diversity, sex accelerates adaptation and removes deleterious mutations. As such, it plays a central role in the origin and success of species. Studies on the major groups within the fungal kingdom have provided significant and wide-ranging contributions on the molecular bases by which sexual identity and reproduction are defined and controlled. Sex in Fungi: Molecular Determination and Evolutionary Implications not only encompasses the current state of knowledge, but also serves as an invaluable resource that will guide new research on these systems and organisms. Since John Raper’s pioneering studies with the basidiomycetes in the 1960s, and the elegant work of Ira Herskowitz with Saccharomyces, genetic, molecular, and genomic analyses of fungal sexual reproduction have helped to illuminate how sexual cycles function in, as well as drive, evolution. The biological principles involved are profound and can serve as general paradigms for how cell identity is established and maintained, how cells sense and respond to extracellular cues, the role of genetic rearrangements in generating changes in cell identity and fate, and how genomic regions governing sexual identity are organized and evolved. Drawing on the great advances made over the past 10 years, this volume provides illuminating insights into the molecular details of cell-type specification, mating-type switching, pheromone perception and signaling, and cellular and nuclear fusion. The tremendous impact of comparative genomics on the analysis of mating is evident in many of the chapters in this book. This volume includes chapters on both model and pathogenic fungi as well as a section that looks forward to what we hope to learn in other fungal lineages. The book concludes with a selection of chapters on the implications of sex, and studies of experimental evolution, in a broader evolutionary context.