Cell division, growth and death - Editorial overview

摘要

The size of a cell population -- whether it is the size of a yeast colony on a grape leaf or the size of a cow's liver -- is determined by the rates of three processes in the cells of that population: division, growth, and death. This issue of Current Opinion in Cell Biology focuses on recent advances in our understanding of these processes - with particular emphasis on mechanisms of cell cycle control and programmed cell death (apoptosis). The eukaryotic cell cycle is governed by a complex regulatory system that generates waves of cyclin-dependent kinase (Cdk) activities that trigger cell cycle events. Although we know a great deal about the individual components of this system, we still possess only a limited understanding of how the myriad connections between these components result in the complex behaviours of the system as a whole: how the system generates switch-like Cdk oscillations that are linked together in a properly timed, coordinated and ordered series. Many of the best insights into this problem have come from studies of the transcriptional network that helps drive the cell cycle in the budding yeast Saccharomyces cerevisiae. A handful of transcription factors arc responsible for controlling many of the hundreds of genes that are expressed at specific cell cycle stages. These transcription factors each control genes that stimulate or inhibit the actions of the other factors, resulting in an interwoven regulatory network that has the potential to produce an autonomous cell cycle oscillator. Progress in our understanding of this oscillator has been bolstered recently by the use of powerful new techniques for genome-wide expression analysis and transcription factor target identification. As reviewed by Futcher (pp 676-683), these new techniques are leading to a comprehensive understanding of the regulatory interactions in this system. This allows us not only to refine our models of yeast cell cycle control, but will undoubtedly lead to important insights into the oscillators that control the cell cycle in multicellular eukaryotes.