The actin-binding protein UNC-115 is an effector of Rac signaling during axon pathfinding in C. elegans

Development. 2003 Feb;130(4):693-704. doi: 10.1242/dev.00300.

Abstract

Rac GTPases control cell shape by regulating downstream effectors that influence the actin cytoskeleton. UNC-115, a putative actin-binding protein similar to human abLIM/limatin, has previously been implicated in axon pathfinding. We have discovered the role of UNC-115 as a downstream cytoskeletal effector of Rac signaling in axon pathfinding. We show that unc-115 double mutants with ced-10 Rac, mig-2 Rac or unc-73 GEF but not with rac-2/3 Rac displayed synthetic axon pathfinding defects, and that loss of unc-115 function suppressed the formation of ectopic plasma membrane extensions induced by constitutively-active rac-2 in neurons. Furthermore, we show that UNC-115 can bind to actin filaments. Thus, UNC-115 is an actin-binding protein that acts downstream of Rac signaling in axon pathfinding.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Actins / metabolism*
  • Amino Acid Sequence
  • Animals
  • Animals, Genetically Modified
  • Axons / physiology*
  • Caenorhabditis elegans / physiology*
  • Caenorhabditis elegans Proteins / genetics
  • Caenorhabditis elegans Proteins / metabolism*
  • Cell Membrane / metabolism
  • Cell Membrane / ultrastructure
  • Green Fluorescent Proteins
  • Luminescent Proteins / genetics
  • Luminescent Proteins / metabolism
  • Microfilament Proteins / genetics
  • Microfilament Proteins / metabolism*
  • Molecular Sequence Data
  • Mutation
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism
  • Neurons / metabolism
  • Neurons / pathology
  • RAC2 GTP-Binding Protein
  • Sequence Homology, Amino Acid
  • rac GTP-Binding Proteins / genetics
  • rac GTP-Binding Proteins / metabolism*

Substances

  • Actins
  • CED-10 protein, C elegans
  • Caenorhabditis elegans Proteins
  • Luminescent Proteins
  • Microfilament Proteins
  • Nerve Tissue Proteins
  • UNC-115 protein, C elegans
  • UNC-73 protein, C elegans
  • Green Fluorescent Proteins
  • Mig-2 protein, C elegans
  • rac GTP-Binding Proteins