Related Experiment Video

Updated: Mar 26, 2026

"Phagosome Closure Assay" to Visualize Phagosome Formation in Three Dimensions Using Total Internal Reflection Fluorescent Microscopy TIRFM
10:07

"Phagosome Closure Assay" to Visualize Phagosome Formation in Three Dimensions Using Total Internal Reflection Fluorescent Microscopy TIRFM

Published on: August 26, 2016

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Dynamin-Actin Cross Talk Contributes to Phagosome Formation and Closure

Florence Marie-Anaïs1,2,3, Julie Mazzolini1,2,3,4, Floriane Herit1,2,3

  • 1Inserm U1016, Institut Cochin, Paris, France.

Traffic (Copenhagen, Denmark)
|February 6, 2016
PubMed

Insights

Dynamin-2 and actin cytoskeleton crosstalk is crucial for macrophage phagocytosis. This study reveals dynamin-2

Area of Science:

  • Cell Biology
  • Immunology
  • Molecular Biology

Background:

  • Phagocytosis is a key cellular process for immune defense and waste removal.
  • Actin cytoskeleton rearrangements drive particle engulfment during phagocytosis.
  • The precise mechanisms of phagosome closure remain incompletely understood.

Purpose of the Study:

  • To elucidate the role of dynamin-2 in the closure and scission steps of phagocytosis.
  • To investigate the interplay between actin and dynamin-2 during phagosome formation.

Main Methods:

  • Utilized Total Internal Reflection Fluorescence Microscopy (TIRFM) in living cells.
  • Monitored three-dimensional phagosome formation and closure dynamics.
  • Employed dominant-negative mutants and drugs to inhibit dynamin-2 activity.

Main Results:

  • Dynamin-2 is recruited early with actin during phagosome formation and accumulates at closure sites.
  • Dynamin-2 inhibition impairs actin dynamics and pseudopod extension.
  • Actin depolymerization affects dynamin-2 recruitment and activity, highlighting a crosstalk.
  • Dynamin-2 is essential for the final scission of the phagosome from the plasma membrane.

Conclusions:

  • Dynamin-2 plays a critical role in the scission phase of phagocytosis.
  • A functional crosstalk between actin and dynamin-2 is established for phagosome formation, closure, and scission.
Keywords:
actindynaminmacrophagesphagocytosispseudopodsscission

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