Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: The nature of cell-cycle checkpoints: facts and fallacies. | Journal of Biology Opinion The nature of cell-cycle checkpoints facts and fallacies Alexey Khodjakov and Conly L Rieder Address Wadsworth Center PO Box 509 Albany NY 12201-0509 USA. Correspondence Alexey Khodjakov. Email khodj@ Conly L Rieder. Email rieder@ Abstract The concept of checkpoint controls revolutionized our understanding of the cell cycle. Here we revisit the defining features of checkpoints and argue that failure to properly appreciate the concept is leading to misinterpretation of experimental results. We illustrate using the mitotic checkpoint problems that can arise from a failure to respect strict definitions and precise terminology. Cell biology is not a notoriously self-critical field. We cell biologists are not reticent about announcing breakthroughs and making promises of imminent revolutions. However one cannot summarize the history of research and thought about mitosis as a progress from primitive glimmerings to modern revelations. Nothing we have learned about mitosis since it was discovered a century ago is as dazzling as the discovery itself 1 . Without doubt each scientific generation gathers more information about mitosis than its predecessors. But despite stunning advances in imaging that allow many of the intimate details of spindle assembly and chromosome behavior to be visualized and concurrent strides in molecular genetics and biochemistry that have identified a plethora of molecules and interactions directly or indirectly required for proper mitosis major conceptual advances are as opined by Daniel Mazia in the quotation above rare. Yet we believe that the concept of cell-cycle checkpoint controls articulated in the late 20th century by Leland Hartwell for which he shared the Nobel Prize in 2001 was a breakthrough to rival the discovery of mitosis itself. Hartwell s idea departed from the traditional view that stage-to-stage progress through the cell cycle occurred whenever there were sufficient means to .