Identification and characterization of the ubiquitously occurring nuclear matrix protein NMP 238.
By systematic comparison of two-dimensional electrophoretic patterns of nuclear matrix proteins an ubiquitously occurring (common) nuclear matrix protein, termed NMP 238, was detected. Localization of the protein in isolated nuclear matrices and in nuclear and cytoplasmic regions of cells was determined by confocal immunofluorescence microscopy. N-terminal protein sequencing, mass spectrometry, and sequencing of a human EST cDNA clone showed identity of the protein with a nuclear protein, termed TIP49, of as yet uncertain function. Expression of the corresponding gene in diverse human and rat cells was confirmed by Northern blotting. The protein displays two nuclear localization signals. Sequence homologies indicate evolutionary related proteins in nematodes, yeast, and archaebacteria. Similarities to the AAA family of proteins and to a subgroup of chaperones suggest that the nuclear matrix protein may play a role in the assembly and ATP-dependent anchorage of proteins.
Holzmann
K
K
Institute of Tumor Biology-Cancer Research, University of Vienna, Borschkegasse 8a, Vienna, A-1090, Austria. Klaus.Holzmann@univie.ac.at
Gerner
C
C
Korosec
T
T
Pöltl
A
A
Grimm
R
R
Sauermann
G
G
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D015180:Electrophoresis, Gel, Two-Dimensional; D006367:HeLa Cells; D006801:Humans; D019169:Jurkat Cells; D020014:K562 Cells; D008297:Male; D008969:Molecular Sequence Data; D015530:Nuclear Matrix / Q000737:chemistry*; D009687:Nuclear Proteins / Q000032:analysis* / Q000737:chemistry / Q000235:genetics; D009928:Organ Specificity; D010802:Phylogeny; D051381:Rats; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014407:Tumor Cells, Cultured
D009687:Nuclear Proteins; C115808:nuclear matrix protein 238