DdLIM is a cytoskeleton-associated protein involved in the protrusion of lamellipodia in Dictyostelium

Mol Biol Cell. 1998 Mar;9(3):545-59. doi: 10.1091/mbc.9.3.545.

Abstract

DdLim, a multi-domain member of the cysteine-rich family of LIM domain proteins, was isolated from Dictyostelium cells where it localizes in lamellipodia and at sites of membrane ruffling. The transcription and expression of DdLim are developmentally regulated, and the timing of its increased association with the actin cytoskeleton coincides with the acquisition in starved cells of a motile, chemotactic behavior. Vegetative cells that overexpress DdLim contain large lamella and exhibit ruffling at the cortex. The high frequency of large, multinucleated mutant cells found in suspension culture suggests that excess DdLim interferes with cytokinesis. DdLim was also identified as a protein in a Dictyostelium cell lysate that associated indirectly, but in a guanosine triphosphate-dependent manner, with a GST-rac1 fusion protein. The data presented suggest that DdLim acts as an adapter protein at the cytoskeleton-membrane interface where it is involved in a receptor-mediated rac1-signaling pathway that leads to actin polymerization in lamellipodia and ultimately cell motility.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / metabolism
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Cell Membrane / physiology
  • Cell Membrane / ultrastructure
  • Cytoskeleton / physiology*
  • DNA, Complementary / genetics
  • DNA, Fungal / genetics
  • DNA, Protozoan / genetics
  • Dictyostelium / genetics
  • Dictyostelium / physiology*
  • Dictyostelium / ultrastructure
  • Fungal Proteins / chemistry
  • Fungal Proteins / genetics
  • Fungal Proteins / physiology
  • GTP-Binding Proteins / metabolism
  • Gene Expression Regulation, Developmental
  • Genes, Fungal
  • Genes, Protozoan
  • Guanosine Triphosphate / metabolism
  • Homeodomain Proteins / chemistry
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / physiology*
  • Microscopy, Electron, Scanning
  • Molecular Sequence Data
  • Movement / physiology
  • Mutation
  • Protozoan Proteins / chemistry
  • Protozoan Proteins / genetics
  • Protozoan Proteins / physiology
  • rac GTP-Binding Proteins

Substances

  • Actins
  • DNA, Complementary
  • DNA, Fungal
  • DNA, Protozoan
  • Fungal Proteins
  • Homeodomain Proteins
  • Protozoan Proteins
  • Guanosine Triphosphate
  • GTP-Binding Proteins
  • rac GTP-Binding Proteins

Associated data

  • GENBANK/U97699