Ferritin was isolated from the fungus Phycomyces blakesleeanus and compared biochemically and immunologically with horse spleen ferritin. Phycomyces and horse spleen ferritins were shown to exhibit similar electrophoretic patterns on polyacrylamide gels. Both preparations yielded an identical single band on sodium dodecyl sulfate-containing polyacrylamide gels. Tryptic digests of Phycomyces fer...

Converging evidence leaves little doubt that a change in the conformation of prion protein (PrP(C)) from a mainly alpha-helical to a beta-sheet rich PrP-scrapie (PrP(Sc)) form is the main event responsible for prion disease associated neurotoxicity. However, neither the mechanism of toxicity by PrP(Sc), nor the normal function of PrP(C) is entirely clear. Recent reports suggest that imbalance o...

By A. MAzUR AND A. CARLETON T HE RESULTS of studies in our laboratory’ lend support to the hypothesis that the release of iron from ferritin stores in the liver is mediated by the enzyme xanthine oxidase acting as a dehydrogenase. In this reaction the reduced enzyme, formed as a result of oxidation of xanthine or hypoxanthine to uric acid, is reoxidized by some of the ferric iron of ferritin wh...

Given the modulation of iron metabolism by hypoxia and the high iron requirement of neoplastic cells, we investigated iron metabolism in a human renal cancer cell line with a mutated von Hippel Lindau (VHL) tumor suppressor gene (RCC10) and in a transfectant clone with wild-type VHL (RCC63). The loss of VHL strongly up-regulated transferrin receptor expression in RCC10 cells as a result of hypo...

BACKGROUND Lung injury caused by both inhaled dusts and infectious agents depends on increased availability of iron and metal-catalyzed oxidative stress. Because inhaled particles, such as silica, and certain infections can cause secondary pulmonary alveolar proteinosis (PAP), we tested the hypothesis that idiopathic PAP is associated with an altered iron homeostasis in the human lung. METHOD...

Ferritin is an iron storage protein expressed in varying concentrations in mammalian cells. The deposition of ferric iron in the core of ferritin makes it a magnetic resonance imaging contrast agent, and ferritin has recently been proposed as a gene expression reporter protein for magnetic resonance imaging. To date, ferritin has been overexpressed in vivo and has been coexpressed with transfer...

Traditionally, transferrin has been considered the primary mechanism for cellular iron delivery, despite suggestive evidence for additional iron delivery mechanisms. In this study we examined ferritin, considered an iron storage protein, as a possible delivery protein. Ferritin consists of H- and L-subunits, and we demonstrated iron uptake by ferritin into multiple organs and that the uptake of...

Urinary ferritin levels were measured by a "2-site" immunoradiometric assay in normal volunteers and in patients with various hematologic disorders. The mean urinary ferritin concentration in normal subjects averaged 2.2 microgram/liter, only 3% of the serum ferritin level. Elevated urinary ferritin levels averaging 45 microgram/liter were observed in patients with hematologic malignancies, but...

The iron-storage protein ferritin was found to be associated with highly purified coated vesicles (CV) from chicken liver. Chicken liver ferritin was morphologically similar to ferritin from horse spleen and could be isolated using a specific anti-ferritin monoclonal antibody. This antibody recognized a 240 X 10(3) Mr form of chicken ferritin but not the 22 X 10(3) Mr ferritin subunit after pro...

The iron and ferritin content of rat liver and the species of ferritin present were examined from 4 days before to 3 weeks after birth. 1. Total iron and ferritin iron accumulated rapidly during the last days of gestation and from the second postnatal day underwent a steady depletion. 2. The amount of iron deposited before birth in the liver of each pup varied inversely with litter size and cou...