Prokaryotic expression of bone sialoprotein and identification of casein kinase II phosphorylation sites

Biochem Biophys Res Commun. 2005 Jul 29;333(2):443-7. doi: 10.1016/j.bbrc.2005.05.124.

Abstract

Bone sialoprotein is an extracellular noncollagenous acidic protein that plays a role in bone mineralization and remodeling. Its expression is restricted to mineralized tissues and is subjected to variety of posttranslational modifications including phosphorylation and glycosylation. We have expressed the full-length and half domains of bovine bone sialoprotein in a prokaryotic system and identified the phosphorylation sites of casein kinase II. The N-terminal automated solid-phase sequencing defined four phosphorylated peptides: residues 28-38 (LEDS(P)EENGVFK), 51-86 (FYPELKRFAVQSSS(P)DS(P)S(P)EENGNGDS(P)S(P)EEEEEEEETS(P)), 151-165 (EDES(P)DEEEEEEEEEE), and 295-305 (GRGYDS(P)YDGQD). Nine phosphoserines were identified within the four peptides. Seven of them were in the N-terminus (S31, S64, S66, S67, S75, S76, and S86) and two were in the C-terminus (S154 and S300) of the protein.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Binding Sites
  • Casein Kinase II / chemistry*
  • Casein Kinase II / metabolism*
  • Escherichia coli / genetics
  • Escherichia coli / metabolism
  • Integrin-Binding Sialoprotein
  • Molecular Sequence Data
  • Phosphorylation
  • Protein Binding
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / metabolism
  • Sialoglycoproteins / chemistry*
  • Sialoglycoproteins / genetics
  • Sialoglycoproteins / metabolism*

Substances

  • Integrin-Binding Sialoprotein
  • Recombinant Proteins
  • Sialoglycoproteins
  • Casein Kinase II