An Iron-Regulated Ferric Reductase Associated with the Absorption of Dietary Iron

@article{Mckie2001AnIF,
  title={An Iron-Regulated Ferric Reductase Associated with the Absorption of Dietary Iron},
  author={A. Mckie and D. Barrow and G. Latunde-Dada and A. Rolfs and G. Sager and E. Mudaly and M. Mudaly and C. Richardson and D. Barlow and A. Bomford and T. Peters and K. Raja and S. Shirali and M. Hediger and F. Farzaneh and R. Simpson},
  journal={Science},
  year={2001},
  volume={291},
  pages={1755 - 1759}
}
The ability of intestinal mucosa to absorb dietary ferric iron is attributed to the presence of a brush-border membrane reductase activity that displays adaptive responses to iron status. We have isolated a complementary DNA, Dcytb (for duodenal cytochrome b), which encoded a putative plasma membrane di-heme protein in mouse duodenal mucosa. Dcytb shared between 45 and 50% similarity to the cytochrome b561 family of plasma membrane reductases, was highly expressed in the brush-border membrane… Expand
Molecular and functional roles of duodenal cytochrome B (Dcytb) in iron metabolism.
TLDR
Dcytb expression and function were modulated by iron and DMT1, both predominantly localised in the apical region of the duodenum were up-regulated in iron deficiency. Expand
The role of duodenal cytochrome b in intestinal iron absorption remains unclear.
TLDR
It is concluded that Dcytb is not necessary for dietary iron absorption in mice, but this conclusion should be interpreted with caution, as no direct measurements of iron absorption were made and the reliance on liver iron levels does not provide unequivocal evidence for or against an absorption defect. Expand
Identification of an Intestinal Heme Transporter
TLDR
A membrane protein named HCP 1 (heme carrier protein 1), with homology to bacterial metal-tetracycline transporters, mediates heme uptake by cells in a temperature-dependent and saturable manner and is indicated to be the long-sought intestinal heme transporter. Expand
Duodenal cytochrome B expression stimulates iron uptake by human intestinal epithelial cells.
TLDR
Dcytb can act as a ferric reductase that stimulates iron uptake in Caco-2 cells, a human cell line model often used to mimic intestinal enterocytes. Expand
The role of Dcytb in iron metabolism: an update.
  • A. Mckie
  • Biology, Medicine
  • Biochemical Society transactions
  • 2008
TLDR
It is revealed that Dcytb is the only iron-regulated ferric reductase in the duodenal mucosa and that loss of D Cytb affects iron absorption, and ascorbate is the likely intracelluar electron donor. Expand
Duodenal mucosal and plasma ascorbate levels of patients with iron deficiency
Summary: Iron is a vital element for almost all living organisms. In mammals iron is taken by the intestinal epithelium, primarily in the duodenum. The initial step of absorption involves theExpand
Structural basis for promotion of duodenal iron absorption by enteric ferric reductase with ascorbate
Dietary iron absorption is regulated by duodenal cytochrome b (Dcytb), an integral membrane protein that catalyzes reduction of nonheme Fe3+ by electron transfer from ascorbate across the membrane.Expand
Duodenal Cytochrome b (DCYTB) in Iron Metabolism: An Update on Function and Regulation
TLDR
The emerging relationship between cellular iron homeostasis, the emergent “IRP1-HIF2α axis”, duodenal cytochrome b (DCYTB) and ascorbate in relation to iron metabolism are discussed. Expand
Structural basis for promotion of duodenal iron absorption by enteric ferric reductase with ascorbate
Dietary iron absorption is regulated by duodenal cytochrome b (Dcytb), an integral membrane protein that catalyzes reduction of nonheme Fe3+ by electron transfer from ascorbate across the membrane.Expand
Cybrd1 (duodenal cytochrome b) is not necessary for dietary iron absorption in mice.
TLDR
It is found that loss of Cybrd1 had little or no impact on body iron stores, even in the setting of iron deficiency, which means that other mechanisms must be available for the reduction of dietary iron. Expand
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