VCP, the mammalian homolog of cdc48, is tyrosine phosphorylated in response to T cell antigen receptor activation.
Activation of T cells through the T cell antigen receptor (TCR) results in the rapid tyrosine phosphorylation of a number of cellular proteins, one of the earliest being a 100 kDa protein. We have sought to identify this 100 kDa substrate by partially purifying the protein by antiphosphotyrosine (APT) affinity purification, in order to obtain amino acid sequence data and, using this information, to isolate the cDNA clone encoding the molecule. We report here that the amino acid sequence data showed pp100 to be the murine equivalent of porcine valosin containing protein (VCP), a finding confirmed from the cloning and sequencing of the murine pp100 cDNA. Sequence analysis has shown VCP to be a member of a family of ATP binding, homo-oligomeric proteins, and the mammalian homolog of Saccharomyces cerevisiae cdc48p, a protein essential to the completion of mitosis in yeast. We also provide proof that both endogenous and expressed murine VCP are tyrosine phosphorylated in response to T cell activation. Thus we have identified a novel component of the TCR mediated tyrosine kinase activation pathway that may provide a link between TCR ligation and cell cycle control.
Egerton
M
M
Cell Biology and Metabolism Branch, National Institute for Child Health and Human Development, NIH, Bethesda, MD 20892.
Ashe
O R
OR
Chen
D
D
Druker
B J
BJ
Burgess
W H
WH
Samelson
L E
LE
D000251:Adenosine Triphosphatases; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018797:Cell Cycle Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D002460:Cell Line; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics / Q000302:isolation & purification; D005260:Female; D005656:Fungal Proteins / Q000235:genetics*; D016259:Genes, myc; D006801:Humans; D008715:Methionine / Q000378:metabolism; D051379:Mice; D008815:Mice, Inbred Strains; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D010766:Phosphorylation; D019000:Phosphotyrosine; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000201:enzymology; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D013552:Swine; D013601:T-Lymphocytes; D014443:Tyrosine / Q000031:analogs & derivatives / Q000032:analysis; D000074405:Valosin Containing Protein
D018797:Cell Cycle Proteins; D005656:Fungal Proteins; D009838:Oligodeoxyribonucleotides; D011948:Receptors, Antigen, T-Cell; D029701:Saccharomyces cerevisiae Proteins; D019000:Phosphotyrosine; D014443:Tyrosine; D004247:DNA; D008715:Methionine; D011505:Protein-Tyrosine Kinases; D000251:Adenosine Triphosphatases; C000614177:CDC48 protein, S cerevisiae; C000614178:VCP protein, human; D000074405:Valosin Containing Protein; C000614179:Vcp protein, mouse