The tetrameric L27 domain complex as an organization platform for supramolecular assemblies

Nat Struct Mol Biol. 2004 May;11(5):475-80. doi: 10.1038/nsmb751. Epub 2004 Mar 28.


L27 domain, initially identified in the Caenorhabditis elegans Lin-2 and Lin-7 proteins, is a protein interaction module that exists in a large family of scaffold proteins. The domain can function as an organization center of large protein assemblies required for establishment and maintenance of cell polarity. We have solved the high-resolution NMR structure of a tetrameric complex of L27 domains containing two SAP97-mLin-2 L27 domain heterodimers. Each L27 domain contains three a-helices. The first two helices of each domain are packed together to form a four-helical bundle in the heterodimer. The third helix of each L27 domain forms another four-helical bundle that assembles the two heterodimers into a tetramer. The structure of the complex provides a mechanistic explanation for L27 domain-mediated polymerization of scaffold proteins, a process that is crucial for the assembly of supramolecular complexes in asymmetric cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Biopolymers / chemistry*
  • Caenorhabditis elegans / chemistry*
  • Caenorhabditis elegans Proteins / chemistry*
  • Chromatography, Gel
  • Helminth Proteins / chemistry*
  • Humans
  • Membrane Proteins / chemistry*
  • Mice
  • Molecular Sequence Data
  • Sequence Homology, Amino Acid


  • Biopolymers
  • Caenorhabditis elegans Proteins
  • Helminth Proteins
  • LIN-7 protein, C elegans
  • Lin-2 protein, C elegans
  • Membrane Proteins

Associated data

  • PDB/1RSO