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Biophysical Assays to Probe the Mechanical Properties of the Interphase Cell Nucleus: Substrate Strain Application and Microneedle Manipulation
16:27

Biophysical Assays to Probe the Mechanical Properties of the Interphase Cell Nucleus: Substrate Strain Application and Microneedle Manipulation

Published on: September 14, 2011

STRUCTURE OF THE MITOTIC SPINDLE IN L STRAIN FIBROBLASTS

A KRISHAN, R C BUCK

    The Journal of Cell Biology
    |March 1, 1965
    PubMed

    Insights

    This study reveals the structure of mitotic spindle tubules in L strain fibroblasts, detailing their origin, connections, and role in forming the mid-body during cell division.

    Area of Science:

    • Cell Biology
    • Cytoskeleton Dynamics
    • Mitosis

    Background:

    • The mitotic spindle is crucial for chromosome segregation during cell division.
    • Understanding the ultrastructure of spindle components provides insight into cell division mechanisms.

    Purpose of the Study:

    • To describe the morphology and arrangement of mitotic spindle tubules in L strain fibroblasts.
    • To elucidate the formation of the stem-body and mid-body during anaphase.

    Main Methods:

    • Transmission electron microscopy was used to examine fixed L strain fibroblasts.
    • Glutaraldehyde and osmium tetroxide fixation preserved cellular structures for ultrastructural analysis.

    Main Results:

    • Mitotic spindles contain numerous 150- to 180-Å tubules originating in the cytoplasm.
    • These tubules extend between centrospheres and to kinetochores, with occasional continuity to centrioles.
    • During anaphase, spindle tubules aggregate to form the stem-body and mid-body structures.

    Conclusions:

    • The study provides detailed ultrastructural evidence of mitotic spindle tubule organization.
    • The findings contribute to understanding the physical basis of chromosome movement and cytokinesis.
    Keywords:
    CELL DIVISIONCELL STRUCTURECYTOPLASMFIBROBLASTS

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