Fernanda Cisneros-Soberanis, Eva L Simpson, Alison J Beckett, Nina Pucekova, Samuel Corless, Natalia Y Kochanova, Ian A Prior, Daniel G Booth, William C Earnshaw
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引用次数: 0
Abstract
Chromosome compaction is a key feature of mitosis and critical for accurate chromosome segregation. However, a precise quantitative analysis of chromosome geometry during mitotic progression is lacking. Here, we use volume electron microscopy to map, with nanometer precision, chromosomes from prometaphase through telophase in human RPE1 cells. During prometaphase, chromosomes acquire a smoother surface, their arms shorten, and the primary centromeric constriction is formed. The chromatin is progressively compacted, ultimately reaching a remarkable nucleosome concentration of over 750 µM in late prometaphase that remains relatively constant during metaphase and early anaphase. Surprisingly, chromosomes then increase their volume in late anaphase prior to deposition of the nuclear envelope. The plateau of total chromosome volume from late prometaphase through early anaphase described here is consistent with proposals that the final stages of chromatin condensation in mitosis involve a limit density, such as might be expected for a process involving phase separation.
期刊介绍:
The Journal of Cell Biology (JCB) is a comprehensive journal dedicated to publishing original discoveries across all realms of cell biology. We invite papers presenting novel cellular or molecular advancements in various domains of basic cell biology, along with applied cell biology research in diverse systems such as immunology, neurobiology, metabolism, virology, developmental biology, and plant biology. We enthusiastically welcome submissions showcasing significant findings of interest to cell biologists, irrespective of the experimental approach.