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Cross-sectional structure of the central mitotic spindle of Diatoma vulgare. Evidence for specific interactions between antiparallel microtubules

During the transition from prometaphase to metaphase, the cross- sectional area of the central spindle of Diatoma decreases by a factor of nearly two, both at the poles and at the region of overlapping microtubules (MTs) near the spindle equator. The density of spindle MT packing stays approximately...

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Detalles Bibliográficos
Formato: Texto
Lenguaje:English
Publicado: The Rockefeller University Press 1979
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2111535/
https://www.ncbi.nlm.nih.gov/pubmed/500789
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collection PubMed
description During the transition from prometaphase to metaphase, the cross- sectional area of the central spindle of Diatoma decreases by a factor of nearly two, both at the poles and at the region of overlapping microtubules (MTs) near the spindle equator. The density of spindle MT packing stays approximately constant throughout mitosis. Optical diffraction analysis of electron micrographs shows that the packing of the MTs at the poles at all stages of mitosis is similar to that expected for a two-dimensional liquid. Analysis of the region of overlap reveals more packing regularity: during prometaphase, a square packing emerges that displays sufficient organization by late metaphase to generate five orders of diffraction; during anaphase the packing in the overlap region shifts to hexagonal; at telophase, it returns to square. From the data provided by serial section reconstructions of the central spindle, it is possible to identify the polarity of almost every spindle MT, that is, to identify one pole with which the MT is associated. Near neighbor analyses of MTs in cross sections of the overlap region show that MTs prefer antiparallel near neighbors. These near neighbors are most often found at a spacing of approximately 40 nm center-to-center, while parallel near neighbors in the zone of overlap are spaced essentially at random. These results are evidence for a specific interaction between antiparallel MTs. In some sections definite bridges between MTs can be seen. Our findings show that certain necessary conditions for a sliding filament model of anaphase spindle elongation are met.
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spelling pubmed-21115352008-05-01 Cross-sectional structure of the central mitotic spindle of Diatoma vulgare. Evidence for specific interactions between antiparallel microtubules J Cell Biol Articles During the transition from prometaphase to metaphase, the cross- sectional area of the central spindle of Diatoma decreases by a factor of nearly two, both at the poles and at the region of overlapping microtubules (MTs) near the spindle equator. The density of spindle MT packing stays approximately constant throughout mitosis. Optical diffraction analysis of electron micrographs shows that the packing of the MTs at the poles at all stages of mitosis is similar to that expected for a two-dimensional liquid. Analysis of the region of overlap reveals more packing regularity: during prometaphase, a square packing emerges that displays sufficient organization by late metaphase to generate five orders of diffraction; during anaphase the packing in the overlap region shifts to hexagonal; at telophase, it returns to square. From the data provided by serial section reconstructions of the central spindle, it is possible to identify the polarity of almost every spindle MT, that is, to identify one pole with which the MT is associated. Near neighbor analyses of MTs in cross sections of the overlap region show that MTs prefer antiparallel near neighbors. These near neighbors are most often found at a spacing of approximately 40 nm center-to-center, while parallel near neighbors in the zone of overlap are spaced essentially at random. These results are evidence for a specific interaction between antiparallel MTs. In some sections definite bridges between MTs can be seen. Our findings show that certain necessary conditions for a sliding filament model of anaphase spindle elongation are met. The Rockefeller University Press 1979-11-01 /pmc/articles/PMC2111535/ /pubmed/500789 Text en This article is distributed under the terms of an Attribution–Noncommercial–Share Alike–No Mirror Sites license for the first six months after the publication date (see http://www.rupress.org/terms). After six months it is available under a Creative Commons License (Attribution–Noncommercial–Share Alike 4.0 Unported license, as described at http://creativecommons.org/licenses/by-nc-sa/4.0/).
spellingShingle Articles
Cross-sectional structure of the central mitotic spindle of Diatoma vulgare. Evidence for specific interactions between antiparallel microtubules
title Cross-sectional structure of the central mitotic spindle of Diatoma vulgare. Evidence for specific interactions between antiparallel microtubules
title_full Cross-sectional structure of the central mitotic spindle of Diatoma vulgare. Evidence for specific interactions between antiparallel microtubules
title_fullStr Cross-sectional structure of the central mitotic spindle of Diatoma vulgare. Evidence for specific interactions between antiparallel microtubules
title_full_unstemmed Cross-sectional structure of the central mitotic spindle of Diatoma vulgare. Evidence for specific interactions between antiparallel microtubules
title_short Cross-sectional structure of the central mitotic spindle of Diatoma vulgare. Evidence for specific interactions between antiparallel microtubules
title_sort cross-sectional structure of the central mitotic spindle of diatoma vulgare. evidence for specific interactions between antiparallel microtubules
topic Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2111535/
https://www.ncbi.nlm.nih.gov/pubmed/500789