An actin-dependent mechanism for long-range vesicle transport

Nat Cell Biol. 2011 Oct 9;13(12):1431-6. doi: 10.1038/ncb2353.

Abstract

Intracellular transport is vital for the function, survival and architecture of every eukaryotic cell. Long-range transport in animal cells is thought to depend exclusively on microtubule tracks. This study reveals an unexpected actin-dependent but microtubule-independent mechanism for long-range transport of vesicles. Vesicles organize their own actin tracks by recruiting the actin nucleation factors Spire1, Spire2 and Formin-2, which assemble an extensive actin network from the vesicles' surfaces. The network connects the vesicles with one another and with the plasma membrane. Vesicles move directionally along these connections in a myosin-Vb-dependent manner to converge and to reach the cell surface. The overall outward-directed movement of the vesicle-actin network is driven by recruitment of vesicles to the plasma membrane in the periphery of the oocyte. Being organized in a dynamic vesicle-actin network allows vesicles to move in a local random manner and a global directed manner at the same time: they can reach any position in the cytoplasm, but also move directionally to the cell surface as a collective. Thus, collective movement within a network is a powerful and flexible mode of vesicle transport.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actin Cytoskeleton / drug effects
  • Actin Cytoskeleton / metabolism*
  • Actins / physiology*
  • Animals
  • Biological Transport, Active / physiology
  • Cytoplasmic Vesicles / metabolism*
  • Female
  • Formins
  • Mice
  • Mice, Mutant Strains
  • Microfilament Proteins / metabolism
  • Nerve Tissue Proteins / metabolism
  • Nuclear Proteins / metabolism
  • Oocytes / cytology
  • Oocytes / metabolism*

Substances

  • Actins
  • Formins
  • Microfilament Proteins
  • Nerve Tissue Proteins
  • Nuclear Proteins
  • Spir-2 protein, mouse
  • Spire1 protein, mouse
  • formin 2 protein, mouse