Intracellular checkpoint controls constitute a network of signal transd- tion pathways that protect cells from external stresses and internal errors. Ext- nal stresses can be generated by the continuous assault of DNA-damaging agents, such as environmental mutagens, ultraviolet (UV) light, ionizing radiation, or the reactive oxygen species that can arise during normal cellular metabolism. In response to any of these assaults on the integrity of the genome, the activation of the network of checkpoint control pathways can lead to diverse cellular responses, such as cell cycle arrest, DNA repair, or elimination of the cell by cell death (apoptosis) if the damage cannot be repaired. Moreover, internal errors can occur during the highly orchestrated replication of the cellular genome and its distribution into daughter cells. Here, the temporal order of these cell cycle events must be strictly enforced-for example, to ensure that DNA replication is c- plete and occurs only once before cell division, or to monitor mitotic spindle assembly, and to prevent exit from mitosis until chromosome segregation has been completed. Thus, well functioning checkpoint mechanisms are central to the maintenance of genomic integrity and the basic viability of cells and, the- fore, are essential for proper development and survival. The importance of proper functioning of checkpoints becomes plainly obvious under conditions in which this control network malfunctions and fails. Depending on the severity and timing, failure of this machinery can lead to embryonic lethality, genetic diseases, and cancer.
Intracellular checkpoint controls constitute a network of signal transduction pathways that protect cells from external stresses and internal errors by means of cell cycle arrest, DNA repair, or apoptosis. Failure of this machinery can lead to embryonic death, genetic diseases, and cancer. In Checkpoint Controls and Cancer, Volume 2: Activation and Regulation Protocols, Axel H. Schönthal, PhD, marshals a prestigious panel of researchers working at the cutting edges of their fields to present readily reproducible experimental protocols for the study of the molecular components of checkpoint controls and their regulation. Described in step-by-step detail, these powerful techniques offer such novel approaches as the use of genome databases and siRNA to analyze how cells of the human body can escape proper surveillance to grow into a tumor. Additional experimental methods are provided for the manipulation of checkpoint pathways and the analysis of the resulting consequences for the cellular phenotype. The earlier first volume, Reviews and Model Systems, comprehensively describes the complexities of checkpoint controls and the model systems available to study them.
Comprehensive and up-to-date, the two volumes of Checkpoint Controls and Cancer offer novice and experienced researchers alike not only entré into the complexities of this vast field, but also to the full panoply of productive tools needed to deepen understanding of the systems, as well as to develop new and more effective therapies.
