Preface/Front Matter

Abstract

In this second volume of the three-volume set The Molecular and Cellular Biology of the Yeast Saccharomyces, the emphasis is on gene expression. A continuing theme of these monographs has been the extent to which basic biological processes have been conserved in the eukaryotic world during evolution. This conservation is particularly striking in those facets of yeast biology reviewed in this volume: the transcriptional machinery, tRNA processing, mRNA splicing, stress and chaperone proteins, ubiquitin-associated functions, the trimeric G-protein-based pheromone response pathway, and chromosomal imprinting. This is an impressive list. At the time of the original monograph, we did not even know that some of these processes occurred in yeast, and for most of them, we had no clue that the molecular underpinnings of these cellular phenomena would resemble so closely those found for similar processes in larger eukaryotes. Even more striking is the fact that these resemblances extend not merely to the molecular outline of the processes, but also to the molecules themselves: Many of the key players in these pathways or complexes show cross-complementation across biological kingdoms.

The circuitry involved in regulating metabolic pathways in yeast is, of course, that required for the yeast life style—hanging out on grapes probably requires a particular focus on regulating carbon and nitrogen metabolism and involves a feast or famine existence. The particular molecular mechanisms effecting this control, however, incorporate the same tried and true eukaryotic themes used elsewhere, namely, activator proteins, acidic blobs for activation domains, helix-loop-helix proteins, leucine zippers, zinc