The major phosphorylation site of nucleophosmin (B23) is phosphorylated by a nuclear kinase II.

Nucleophosmin (B23) was phosphorylated in vitro with [gamma-32P]ATP and a nuclear kinase (type II) purified from HeLa cells. The phosphorylation was inhibited by heparin and by 2,3-diphosphoglycerate. Peptide mapping analysis indicated that the phosphorylation site in vitro was identical to that in vivo. Purified nucleoli have a similar kinase that phosphorylated nucleophosmin at the same site. These results indicated that nucleophosmin is phosphorylated in vivo by a nucleolar kinase (type II).

[1]  J. Labbé,et al.  Identification of major nucleolar proteins as candidate mitotic substrates of cdc2 kinase , 1990, Cell.

[2]  C. Lehner,et al.  Major nucleolar proteins shuttle between nucleus and cytoplasm , 1989, Cell.

[3]  Qing-Rong Liu,et al.  Characterization of the cDNA encoding human nucleophosmin and studies of its role in normal and abnormal growth. , 1989, Biochemistry.

[4]  J. Chang,et al.  cDNA and deduced primary structure of rat protein B23, a nucleolar protein containing highly conserved sequences. , 1988, The Journal of biological chemistry.

[5]  N. Feuerstein,et al.  Identification of numatrin, the nuclear matrix protein associated with induction of mitogenesis, as the nucleolar protein B23. Implication for the role of the nucleolus in early transduction of mitogenic signals. , 1988, The Journal of biological chemistry.

[6]  F. A. Anderer,et al.  Casein kinase II accumulation in the nucleolus and its role in nucleolar phosphorylation. , 1988, Biochimica et biophysica acta.

[7]  B. Yung,et al.  Identification and characterization of a hexameric form of nucleolar phosphoprotein B23. , 1987, Biochimica et biophysica acta.

[8]  W. Franke,et al.  A constitutive nucleolar protein identified as a member of the nucleoplasmin family. , 1987, The EMBO journal.

[9]  L. Cox,et al.  Nucleoplasmin cDNA sequence reveals polyglutamic acid tracts and a cluster of sequences homologous to putative nuclear localization signals. , 1987, The EMBO journal.

[10]  R. Cook,et al.  Amino acid sequence of protein B23 phosphorylation site. , 1986, The Journal of biological chemistry.

[11]  H. Busch,et al.  Translocation of nucleolar phosphoprotein B23 (37 kDa/pI 5.1) induced by selective inhibitors of ribosome synthesis. , 1985, Biochimica et biophysica acta.

[12]  M. Goodenough,et al.  Topoisomerase I phosphorylation in vitro and in rapidly growing Novikoff hepatoma cells. , 1985, The EMBO journal.

[13]  N. Osheroff,et al.  Phosphorylation of DNA topoisomerase II by casein kinase II: modulation of eukaryotic topoisomerase II activity in vitro. , 1985, Proceedings of the National Academy of Sciences of the United States of America.

[14]  H. Busch,et al.  Actinomycin D inhibition of monoclonal antibody binding to nucleolar phosphoprotein 37/5.2 (B23). , 1984, Life sciences.

[15]  A. Inoue,et al.  Heterogeneity of protein kinase NII from rat liver nuclei. , 1984, Biochemical and biophysical research communications.

[16]  H. Busch,et al.  Purification of a protein kinase from human Namalwa cells that phosphorylates topoisomerase I. , 1982, Biochemical and biophysical research communications.

[17]  A Aitken,et al.  Separation and characterisation of glycogen synthase kinase 3, glycogen synthase kinase 4 and glycogen synthase kinase 5 from rabbit skeletal muscle. , 1982, European journal of biochemistry.

[18]  G. Hathaway,et al.  Casein kinases--multipotential protein kinases. , 1982, Current topics in cellular regulation.

[19]  S. Jacob,et al.  Protein kinase activity of RNA polymerase I purified from a rat hepatoma: probable function of Mr 42,000 and 24,600 polypeptides. , 1981, Proceedings of the National Academy of Sciences of the United States of America.

[20]  W. Earnshaw,et al.  Assembly of nucleosomes: the reaction involving X. laevis nucleoplasmin , 1980, Cell.

[21]  E. Krebs,et al.  Phosphorylation-dephosphorylation of enzymes. , 1979, Annual review of biochemistry.

[22]  L. Kleinsmith Phosphorylation of non‐histone proteins in the regulation of chromosome structure and function , 1975, Journal of cellular physiology.

[23]  M. Olson,et al.  Phosphorylation of proteins of ribosomes and nucleolar preribosomal particles from Novikoff hepatmoa ascites cells. , 1974, Journal of molecular biology.

[24]  D. Schmoll,et al.  Comparison of proteins of ribosomal subunits and nucleolar preribosomal particles from Novikoff hepatoma ascites cells by two-dimensional polyacrylamide gel electrophoresis. , 1974, Biochemistry.