TY - JOUR
AU - Ratcliffe, Peter J.
AB - <p>Post-translational hydroxylation has been considered an unusual modification on intracellular proteins. However, following the recognition that oxygen-sensitive prolyl and asparaginyl hydroxylation are central to the regulation of the transcription factor hypoxia-inducible factor (HIF), interest has centered on the possibility that these enzymes may have other substrates in the proteome. In support of this certain ankyrin repeat domain (ARD)-containing proteins, including members of the IκB and Notch families, have been identified as alternative substrates of the HIF asparaginyl hydroxylase factor inhibiting HIF (FIH). Although these findings imply a potentially broad range of substrates for FIH, the precise extent of this range has been difficult to determine because of the difficulty of capturing transient enzyme-substrate interactions. Here we describe the use of pharmacological "substrate trapping" together with stable isotope labeling by amino acids in cell culture (SILAC) technology to stabilize and identify potential FIH-substrate interactions by mass spectrometry. To pursue these potential FIH substrates we used conventional data-directed tandem MS together with alternating low/high collision energy tandem MS to assign and quantitate hydroxylation at target asparaginyl residues. Overall the work has defined 13 new FIH-dependent hydroxylation sites with a degenerate consensus corresponding to that of the ankyrin repeat and a range of ARD-containing proteins as actual and potential substrates for FIH. Several ARD-containing proteins were multiply hydroxylated, and detailed studies of one, Tankyrase-2, revealed eight sites that were differentially sensitive to FIH-catalyzed hydroxylation. These findings indicate that asparaginyl hydroxylation is likely to be widespread among the ∼300 ARD-containing species in the human proteome.</p>
TI - Proteomics-based Identification of Novel Factor Inhibiting Hypoxia-inducible Factor (FIH) Substrates Indicates Widespread Asparaginyl Hydroxylation of Ankyrin Repeat Domain-containing Proteins
JF - Molecular & Cellular Proteomics
DO - 10.1074/mcp.m800340-mcp200
DA - 2009-03-01
UR - https://www.deepdyve.com/lp/american-society-for-biochemistry-and-molecular-biology/proteomics-based-identification-of-novel-factor-inhibiting-hypoxia-Wys6OnYvJb
SP - 535
EP - 546
VL - 8
IS - 3
DP - DeepDyve
ER -