2xum
FACTOR INHIBITING HIF (FIH) Q239H MUTANT IN COMPLEX WITH ZN(II), NOG AND ASP-SUBSTRATE PEPTIDE (20-MER)FACTOR INHIBITING HIF (FIH) Q239H MUTANT IN COMPLEX WITH ZN(II), NOG AND ASP-SUBSTRATE PEPTIDE (20-MER)
Structural highlights
FunctionHIF1N_HUMAN Hydroxylates HIF-1 alpha at 'Asp-803' in the C-terminal transactivation domain (CAD). Functions as an oxygen sensor and, under normoxic conditions, the hydroxylation prevents interaction of HIF-1 with transcriptional coactivators including Cbp/p300-interacting transactivator. Involved in transcriptional repression through interaction with HIF1A, VHL and histone deacetylases. Hydroxylates specific Asn residues within ankyrin repeat domains (ARD) of NFKB1, NFKBIA, NOTCH1, ASB4, PPP1R12A and several other ARD-containing proteins. Also hydroxylates Asp and His residues within ARDs of ANK1 and TNKS2, respectively. Negatively regulates NOTCH1 activity, accelerating myogenic differentiation. Positively regulates ASB4 activity, promoting vascular differentiation.[1] [2] [3] [4] [5] [6] [7] [8] Publication Abstract from PubMedFactor-inhibiting hypoxia-inducible factor (FIH) catalyzes the beta-hydroxylation of an asparagine residue in the C-terminal transcriptional activation domain of the hypoxia inducible factor (HIF), a modification that negatively regulates HIF transcriptional activity. FIH also catalyzes the hydroxylation of highly conserved Asn residues within the ubiquitous ankyrin repeat domain (ARD)-containing proteins. Hydroxylation has been shown to stabilize localized regions of the ARD fold in the case of a three-repeat consensus ankyrin protein, but this phenomenon has not been demonstrated for the extensive naturally occurring ARDs. Here we report that the cytoskeletal ankyrin family are substrates for FIH-catalyzed hydroxylations. We show that the ARD of ankyrinR is multiply hydroxylated by FIH both in vitro and in endogenous proteins purified from human and mouse erythrocytes. Hydroxylation of the D34 region of ankyrinR ARD (ankyrin repeats 13-24) increases its conformational stability and leads to a reduction in its interaction with the cytoplasmic domain of band 3 (CDB3), demonstrating the potential for FIH-catalyzed hydroxylation to modulate protein-protein interactions. Unexpectedly we found that aspartate residues in ankyrinR and ankyrinB are hydroxylated and that FIH-catalyzed aspartate hydroxylation also occurs in other naturally occurring AR sequences. The crystal structure of an FIH variant in complex with an Asp-substrate peptide together with NMR analyses of the hydroxylation product identifies the 3S regio- and stereoselectivity of the FIH-catalyzed Asp hydroxylation, revealing a previously unprecedented posttranslational modification. Asparagine and aspartate hydroxylation of the cytoskeletal ankyrin family is catalyzed by factor-inhibiting hypoxia-inducible factor.,Yang M, Ge W, Chowdhury R, Claridge TD, Kramer HB, Schmierer B, McDonough MA, Gong L, Kessler BM, Ratcliffe PJ, Coleman ML, Schofield CJ J Biol Chem. 2011 Mar 4;286(9):7648-60. Epub 2010 Dec 22. PMID:21177872[9] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
| ||||||||||||||||||