Characterization of the interaction between Actinin-Associated LIM Protein (ALP) and the rod domain of alpha-actinin

BMC Cell Biol. 2009 Mar 27;10:22. doi: 10.1186/1471-2121-10-22.

Abstract

Background: The PDZ-LIM proteins are a family of signalling adaptors that interact with the actin cross-linking protein, alpha-actinin, via their PDZ domains or via internal regions between the PDZ and LIM domains. Three of the PDZ-LIM proteins have a conserved 26-residue ZM motif in the internal region, but the structure of the internal region is unknown.

Results: In this study, using circular dichroism and nuclear magnetic resonance (NMR), we showed that the ALP internal region (residues 107-273) was largely unfolded in solution, but was able to interact with the alpha-actinin rod domain in vitro, and to co-localize with alpha-actinin on stress fibres in vivo. NMR analysis revealed that the titration of ALP with the alpha-actinin rod domain induces stabilization of ALP. A synthetic peptide (residues 175-196) that contained the N-terminal half of the ZM motif was found to interact directly with the alpha-actinin rod domain in surface plasmon resonance (SPR) measurements. Short deletions at or before the ZM motif abrogated the localization of ALP to actin stress fibres.

Conclusion: The internal region of ALP appeared to be largely unstructured but functional. The ZM motif defined part of the interaction surface between ALP and the alpha-actinin rod domain.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actinin / chemistry*
  • Actinin / metabolism
  • Amino Acid Motifs
  • Amino Acid Sequence
  • Cell Line, Tumor
  • Fluorescent Dyes / chemistry
  • Humans
  • LIM Domain Proteins
  • Microfilament Proteins / biosynthesis
  • Microfilament Proteins / chemistry*
  • Microfilament Proteins / metabolism
  • Molecular Sequence Data
  • Peptides / chemical synthesis
  • Peptides / metabolism
  • Protein Binding
  • Protein Structure, Tertiary
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / isolation & purification
  • Recombinant Proteins / metabolism
  • Surface Plasmon Resonance

Substances

  • Fluorescent Dyes
  • LIM Domain Proteins
  • Microfilament Proteins
  • PDLIM3 protein, human
  • Peptides
  • Recombinant Proteins
  • Actinin