pubmed:abstractText |
The ERYTHROPOIETIN (EPO) gene is regulated by the transcription factor Hypoxia Inducible Factor-alpha (HIF-alpha). In this pathway, Prolyl Hydroxylase Domain protein 2 (PHD2) hydroxylates two prolyl residues in HIF-alpha, which in turn promotes HIF-alpha degradation by the von Hippel Lindau (VHL) protein. Evidence that HIF-2alpha is the important isoform for EPO regulation in humans comes from the recent observation that mutations in the HIF2A gene are associated with cases of erythrocytosis. We report here a new erythrocytosis-associated mutation, p.Asp539Glu, in the HIF2A gene. Similar to all reported cases, the affected residue is in close vicinity and C-terminal to the primary hydroxylation site in HIF-2alpha, Pro531. This mutation, however, is notable in producing a rather subtle amino acid substitution. Nonetheless, we find that this mutation compromises binding of HIF-2alpha to both PHD2 and VHL, and we propose that this mutation is the cause of erythrocytosis in this individual.
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pubmed:affiliation |
Laboratory for Red Blood Cell Research, Department of Clinical Chemistry and Haematology, University Medical Center Utrecht, Utrecht, the Netherlands.
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pubmed:publicationType |
Journal Article,
Case Reports,
Research Support, Non-U.S. Gov't,
Research Support, N.I.H., Extramural
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