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Microtubule polarity confers direction to pigment transport in chromatophores

M A McNiven, K R Porter

    The Journal of Cell Biology
    |October 1, 1986
    PubMed

    Insights

    Microtubule polarity guides organelle movement in melanophores. Stabilizing microtubules with taxol delays pigment transport direction changes, suggesting polarity dictates cellular transport direction.

    Area of Science:

    • Cell Biology
    • Cytoskeletal Dynamics

    Background:

    • Cellular mechanisms for organelle transport are not fully understood.
    • Microtubule structural polarity is hypothesized to influence organelle translocation direction.

    Purpose of the Study:

    • To investigate the role of microtubule orientation in pigment transport direction within melanophore arms.
    • To determine if microtubule repolarization is essential for reversing pigment transport direction.

    Main Methods:

    • Surgically severed melanophore arms were used to examine pigment transport.
    • Taxol was employed to stabilize microtubules and assess its effect on reorientation and transport.
    • Pigment movement was monitored in isolated arms with taxol-stabilized microtubules.

    Main Results:

    • Taxol treatment delayed both microtubule reorientation and the reversal of pigment transport direction.
    • This delay was observed in a concentration-dependent manner with increasing taxol concentrations.
    • Data indicate a strong correlation between microtubule repolarization and pigment transport direction reversal.

    Conclusions:

    • Microtubule polarity within melanophores is a key factor in conferring directionality to pigment transport.
    • The findings support the hypothesis that the intrinsic polarity of microtubules governs organelle movement direction.

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