Molecular characterization of human tensin

Biochem J. 2000 Oct 15;351 Pt 2(Pt 2):403-11.


Tensin is a focal-adhesion molecule that binds to actin filaments and interacts with phosphotyrosine-containing proteins. To analyse tensin's function in mammals, we have cloned tensin cDNAs from human and cow. The isolated approx. 7.7-kb human cDNA contains an open reading frame encoding 1735 amino acid residues. The amino acid sequence of human tensin shares 60% identity with chicken tensin, and contains all the structural features described previously in chicken tensin. This includes the actin-binding domains, the Src homology domain 2, and the region similar to a tumour suppressor, PTEN. Two major differences between human and chicken tensin are (i) the lack of the first 54 residues present in chicken tensin, and (ii) the addition of 34- and 38-residue inserts in human and bovine tensin. In addition, our interspecies sequencing data have uncovered the presence of a glutamine/CAG repeat that appears to have expanded in the course of evolution. Northern-blot analysis reveals a 10-kb message in most of the human tissues examined. An additional 9-kb message is detected in heart and skeletal muscles. The molecular mass predicted from the human cDNA is 185 kDa, although both endogenous and recombinant human tensin migrate as 220-kDa proteins on SDS/PAGE. The discrepancy is due to the unusually low electrophoretic mobility of the central region of the tensin polypeptide (residues 306-981). A survey of human prostate and breast cancer cell lines by Western-blot analysis shows a lack of tensin expression in most cancer cell lines, whereas these lines express considerable amounts of focal-adhesion molecules such as talin and focal-adhesion kinase. Finally, tensin is rapidly cleaved by a focal-adhesion protease, calpain II. Incubation of cells with a calpain inhibitor, MDL, prevented tensin cleavage and induced morphological change in these cells, suggesting that cleavage of tensin and other focal-adhesion constituents by calpain disrupts maintenance of normal cell shape.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3 Cells
  • Amino Acid Sequence
  • Animals
  • Blotting, Northern
  • Blotting, Western
  • Breast Neoplasms / metabolism
  • Calpain / antagonists & inhibitors
  • Calpain / metabolism
  • Cattle
  • Chickens
  • Cloning, Molecular
  • DNA, Complementary / metabolism
  • Electrophoresis, Polyacrylamide Gel
  • Female
  • Gene Library
  • Glutathione Transferase / metabolism
  • Humans
  • Male
  • Mice
  • Microfilament Proteins / chemistry*
  • Microfilament Proteins / genetics*
  • Microscopy, Fluorescence
  • Molecular Sequence Data
  • Open Reading Frames
  • Prostatic Neoplasms / metabolism
  • Protein Structure, Tertiary
  • Recombinant Fusion Proteins / metabolism
  • Recombinant Proteins / metabolism
  • Sequence Homology, Amino Acid
  • Tensins
  • Time Factors
  • Tissue Distribution
  • Transfection
  • Tumor Cells, Cultured


  • DNA, Complementary
  • Microfilament Proteins
  • Recombinant Fusion Proteins
  • Recombinant Proteins
  • Tensins
  • Glutathione Transferase
  • Calpain