Purification of native survival of motor neurons complexes and identification of Gemin6 as a novel component

J Biol Chem. 2002 Mar 1;277(9):7540-5. doi: 10.1074/jbc.M110141200. Epub 2001 Dec 17.


The survival of motor neurons (SMN) protein, the product of the gene responsible for the motor neuron degenerative disease spinal muscular atrophy (SMA), is part of a large macromolecular complex. The SMN complex is localized in both the cytoplasm and the nucleus and contains SMN, Gemin2, Gemin3, Gemin4, Gemin5, and a few not yet identified proteins. The SMN complex plays a key role in the biogenesis of spliceosomal small nuclear ribonucleoproteins (snRNPs) and other ribonucleoprotein particles. As a step toward the complete characterization of the components of the SMN complex, we generated stable cell lines that express FLAG-tagged SMN or Gemin2 under the control of a tetracycline-inducible promoter. Native SMN complexes of identical protein composition to those isolated by immunoprecipitation with anti-SMN antibodies were purified by affinity chromatography from extracts of both cell lines. Here we report the identification by mass spectrometry of a novel protein component of the SMN complex termed Gemin6. Co-immunoprecipitation, immunolocalization, and in vitro binding experiments demonstrate that Gemin6 is a component of the SMN complex that localizes to gems and interacts with several Sm proteins of the spliceosomal snRNPs.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Blotting, Western
  • Cell Line
  • Cell Survival
  • DNA / metabolism
  • HeLa Cells
  • Humans
  • Mass Spectrometry
  • Microscopy, Fluorescence
  • Molecular Sequence Data
  • Motor Neurons / cytology*
  • Nerve Tissue Proteins / biosynthesis*
  • Nerve Tissue Proteins / chemistry
  • Nerve Tissue Proteins / genetics
  • Nuclear Proteins*
  • Precipitin Tests
  • Promoter Regions, Genetic
  • Protein Binding
  • Recombinant Fusion Proteins / metabolism
  • Ribonucleoproteins, Small Nuclear
  • SMN Complex Proteins
  • Sequence Homology, Amino Acid
  • Spliceosomes / metabolism


  • GEMIN6 protein, human
  • Nerve Tissue Proteins
  • Nuclear Proteins
  • Recombinant Fusion Proteins
  • Ribonucleoproteins, Small Nuclear
  • SMN Complex Proteins
  • DNA

Associated data

  • GENBANK/AF453443