Editors' ChoiceBiochemistry

Back Door to Phosphorylation

STKE  21 Dec 2004:
Vol. 2004, Issue 264, pp. tw455
DOI: 10.1126/stke.2642004tw455

Protein phosphorylation typically occurs through the catalytic activity of a kinase that transfers the phosphate moiety from adenosine triphosphate to a substrate. Saiardi et al. (see the Perspective by York and Hunter) show that the inositol pyrophosphate IP7 can act as a phosphate donor to eukaryotic proteins. The nonenzymatic covalent protein modification was observed in cell extracts and in yeast cells. Because IP7 and many of its targets have been implicated in various biological processes, this type of phosphorylation may represent an intracellular signaling mechanism.

A. Saiardi, R. Bhandari, A. C. Resnick, A. M. Snowman, S. H. Snyder, Phosphorylation of proteins by inositol pyrophosphates. Science 306, 2101-2105 (2004). [Abstract] [Full Text]

J. D. York, T. Hunter, Unexpected mediators of protein phosphorylation. Science 306, 2053-2055 (2004). [Summary] [Full Text]