The SMN complex, an assemblyosome of ribonucleoproteins

Curr Opin Cell Biol. 2002 Jun;14(3):305-12. doi: 10.1016/s0955-0674(02)00332-0.

Abstract

Spinal muscular atrophy is a common, often lethal, neurodegenerative disease that results from low levels of, or loss-of-function mutations in, the SMN (survival of motor neurons) protein. SMN oligomerizes and forms a stable complex with five additional proteins: Gemins 2-6. SMN also interacts with several additional proteins referred to as "substrates". Most of these substrates contain a domain enriched in arginine and glycine residues (the RG-rich domain), and are constituents of different ribonucleoprotein complexes. Recent studies revealed that the substrates can be modified by an arginine methyltransferase complex, the methylosome. This forms symmetrical dimethylarginines within the RG-rich domains of the substrates, thereby converting them to high-affinity binders of the SMN complex, and most likely providing regulation of the ribonucleoprotein assembly processes.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Cell Nucleus / chemistry
  • Cell Nucleus / metabolism
  • Cyclic AMP Response Element-Binding Protein
  • Cytoplasm / chemistry
  • Humans
  • Intracellular Signaling Peptides and Proteins
  • Macromolecular Substances
  • Methyltransferases / metabolism
  • Models, Genetic
  • Molecular Sequence Data
  • Nerve Tissue Proteins / analysis
  • Nerve Tissue Proteins / physiology*
  • Protein Structure, Tertiary
  • Protein-Arginine N-Methyltransferases
  • RNA-Binding Proteins
  • Ribonucleoproteins / biosynthesis*
  • SMN Complex Proteins

Substances

  • Cyclic AMP Response Element-Binding Protein
  • Intracellular Signaling Peptides and Proteins
  • Macromolecular Substances
  • Nerve Tissue Proteins
  • RNA-Binding Proteins
  • Ribonucleoproteins
  • SMN Complex Proteins
  • Methyltransferases
  • PRMT2 protein, human
  • Protein-Arginine N-Methyltransferases