Cloning and functional characterization of a new Ski homolog, Fussel-18, specifically expressed in neuronal tissues

Lab Invest. 2005 Nov;85(11):1330-41. doi: 10.1038/labinvest.3700344.

Abstract

The Sloan Kettering Virus (Ski) family of nuclear oncoproteins represses transforming growth factor-beta (TGF-beta) signaling through inhibition of transcriptional activity of Smad proteins. Here, we report the discovery of a new functional Smad suppressing element on chromosome 18 (Fussel-18). Fussel-18 encodes for a protein of 297 amino acids sharing characteristic structural features, significant homology and similar genomic organization with the homolog Ski family members, Ski and Ski-related novel sequence (Sno). In contrast to Ski and Sno, which are ubiquitously expressed in human tissues, in situ hybridization, RT-PCR, Western blot and immunohistochemistry revealed a highly specific expression pattern for Fussel-18 in neuronal tissues, especially in the cerebellum, the spinal cord and dorsal root ganglia, during both embryogenesis and adult stage. Functionally, we determined interaction of Fussel-18 with Smad 2 and Smad 3 together with an inhibitory activity on TGF-beta signaling. Fussel-18 is the first example of a Smad-binding protein with a highly restricted expression pattern within the nervous system.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Motifs
  • Amino Acid Sequence
  • Animals
  • Bone Morphogenetic Proteins / genetics
  • Bone Morphogenetic Proteins / metabolism
  • Cell Line
  • Cell Line, Tumor
  • Chromosomes, Human, Pair 18*
  • Cloning, Molecular*
  • Conserved Sequence
  • Embryonic Development
  • Gene Expression
  • Humans
  • Intracellular Signaling Peptides and Proteins
  • Mice
  • Molecular Sequence Data
  • Molecular Weight
  • Nerve Tissue / metabolism*
  • Nerve Tissue Proteins / chemistry
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism
  • Oncogene Proteins / chemistry
  • Oncogene Proteins / genetics
  • Oncogene Proteins / metabolism
  • Protein Structure, Tertiary
  • Proto-Oncogene Proteins / chemistry
  • Proto-Oncogene Proteins / genetics*
  • Proto-Oncogene Proteins / metabolism*
  • RNA, Messenger / metabolism
  • Sequence Homology, Amino Acid
  • Smad2 Protein / metabolism
  • Smad3 Protein / metabolism
  • Transforming Growth Factor beta / antagonists & inhibitors
  • Transforming Growth Factor beta / genetics

Substances

  • Bone Morphogenetic Proteins
  • Intracellular Signaling Peptides and Proteins
  • Nerve Tissue Proteins
  • Nuclear Proteins
  • Oncogene Proteins
  • Proto-Oncogene Proteins
  • RNA, Messenger
  • SKIL protein, human
  • SKOR2 protein, human
  • Smad2 Protein
  • Smad3 Protein
  • Transforming Growth Factor beta