Molecular cloning of matrin 3. A 125-kilodalton protein of the nuclear matrix contains an extensive acidic domain

J Biol Chem. 1991 May 25;266(15):9893-9.


We report here the cloning and sequencing of matrin 3, an acidic internal matrix protein, from a rat insuloma cDNA library. The nucleotide sequence has a single open reading frame encoding a polypeptide of 845 amino acids. The Genbank and National Biomedical Research Foundation databases did not contain any sequences similar to that of matrin 3. The primary structure consists of 33% charged residues and is generally hydrophilic. The amino-terminal region (residues 1-120) is positively charged and contains a large number of amino acids with free hydroxyl groups (26 of the first 100 residues) as in the lamins and several non-lamin intermediate filament proteins. A highly acidic domain (approximately 170 amino acids) near the carboxyl terminus, in which 32% of the amino acid residues are acidic (Glu or Asp), is a characteristic found in other nuclear proteins (Earnshaw, W. C. (1987) J. Cell Biol. 105, 1479-1482). A putative nuclear targeting signal sequence (Ser-Lys-Lys-Lys-Leu-Lys-Lys-Val-Glu) is located in the middle of the highly acidic domain. The corresponding human deduced partial amino acid sequence is 96% identical to the rat sequence, indicating that matrin 3 is a highly conserved protein.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies
  • Antigens, Nuclear
  • Base Sequence
  • Blotting, Northern
  • Blotting, Western
  • Cloning, Molecular
  • DNA / genetics
  • Fluorescent Antibody Technique
  • HeLa Cells
  • Humans
  • Hydrogen-Ion Concentration
  • Molecular Sequence Data
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / genetics*
  • Nuclear Proteins / immunology
  • RNA, Messenger / analysis
  • RNA-Binding Proteins
  • Rats
  • Sequence Homology, Nucleic Acid
  • Tumor Cells, Cultured


  • Antibodies
  • Antigens, Nuclear
  • Nuclear Proteins
  • RNA, Messenger
  • RNA-Binding Proteins
  • matrin 3, rat
  • DNA

Associated data

  • GENBANK/M60691
  • GENBANK/M60692
  • GENBANK/M60693
  • GENBANK/M60694
  • GENBANK/M60695
  • GENBANK/M60696
  • GENBANK/M60697
  • GENBANK/M63483
  • GENBANK/M63485
  • GENBANK/M74176