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

Biochem J. 1990 Sep 1;270(2):549-52. doi: 10.1042/bj2700549.

Abstract

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).

Publication types

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

MeSH terms

  • 2,3-Diphosphoglycerate
  • Amino Acid Sequence
  • Binding Sites
  • Cell Nucleolus / enzymology
  • Cell Nucleus / enzymology*
  • Diphosphoglyceric Acids / pharmacology
  • HeLa Cells
  • Heparin / pharmacology
  • Humans
  • Molecular Sequence Data
  • Nuclear Proteins / metabolism*
  • Nucleophosmin
  • Peptide Mapping
  • Phosphorylation
  • Protein Kinases / metabolism*

Substances

  • Diphosphoglyceric Acids
  • NPM1 protein, human
  • Nuclear Proteins
  • Nucleophosmin
  • 2,3-Diphosphoglycerate
  • Heparin
  • Protein Kinases
  • protein kinase NII