• Record: found
  • Abstract: found
  • Article: not found

Secreted kinase phosphorylates extracellular proteins that regulate biomineralization.

Science (New York, N.Y.)

Substrate Specificity, Secretory Pathway, secretion, metabolism, chemistry, Recombinant Fusion Proteins, Protein Sorting Signals, Phosphorylation, genetics, Osteosclerosis, Osteopontin, Mutation, Molecular Sequence Data, enzymology, Milk, Microcephaly, Humans, HeLa Cells, HEK293 Cells, Golgi Apparatus, Glycoproteins, Extracellular Matrix Proteins, Exophthalmos, Cleft Palate, Cell Line, Tumor, Cattle, Caseins, Casein Kinases, Casein Kinase I, Calcification, Physiologic, Animals, Amino Acid Sequence, Amino Acid Motifs, Abnormalities, Multiple

Read this article at

      There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.


      Protein phosphorylation is a fundamental mechanism regulating nearly every aspect of cellular life. Several secreted proteins are phosphorylated, but the kinases responsible are unknown. We identified a family of atypical protein kinases that localize within the Golgi apparatus and are secreted. Fam20C appears to be the Golgi casein kinase that phosphorylates secretory pathway proteins within S-x-E motifs. Fam20C phosphorylates the caseins and several secreted proteins implicated in biomineralization, including the small integrin-binding ligand, N-linked glycoproteins (SIBLINGs). Consequently, mutations in Fam20C cause an osteosclerotic bone dysplasia in humans known as Raine syndrome. Fam20C is thus a protein kinase dedicated to the phosphorylation of extracellular proteins.

      Related collections

      Author and article information



      Comment on this article