Hiromi Gunshin

Bio: Hiromi Gunshin is an academic researcher from Brigham and Women's Hospital. The author has contributed to research in topics: DMT1 & Membrane protein. The author has an hindex of 3, co-authored 4 publications receiving 2947 citations.

Cloning and characterization of a mammalian proton-coupled metal-ion transporter

Abstract: Metal ions are essential cofactors for a wealth of biological processes, including oxidative phosphorylation, gene regulation and free-radical homeostasis. Failure to maintain appropriate levels of metal ions in humans is a feature of hereditary haemochromatosis, disorders of metal-ion deficiency, and certain neurodegenerative diseases. Despite their pivotal physiological roles, however, there is no molecular information on how metal ions are actively absorbed by mammalian cells. We have now identified a new metal-ion transporter in the rat, DCT1, which has an unusually broad substrate range that includes Fe2+, Zn2+, Mn2+, Co2+, Cd2+, Cu2+, Ni2+ and Pb2+. DCT1 mediates active transport that is proton-coupled and depends on the cell membrane potential. It is a 561-amino-acid protein with 12 putative membrane-spanning domains and is ubiquitously expressed, most notably in the proximal duodenum. DCT1 is upregulated by dietary iron deficiency, and may represent a key mediator of intestinal iron absorption. DCT1 is a member of the 'natural-resistance-associated macrophage protein' (Nramp) family and thus its properties provide insight into how these proteins confer resistance to pathogens.

Expression cloning using Xenopus laevis oocytes.

Abstract: Publisher Summary This chapter describes expression cloning using Xenopus laevis oocytes. Expression cloning using Xenopus laevis oocytes is a unique technique that has resolved many problems of isolating integral membrane proteins because complementary DNA (cDNA) clones are selected directly for their ability to induce the desired function in oocytes and no probes or antibodies are required for screening cDNA libraries. For the experimental biologist, the Xenopus oocyte as an expression system offers several unique features. The oocyte is a large cell making it convenient for RNA microinjection and two-electrode voltage clamp studies. In addition, the cell is in a relatively silent state and exhibits low levels of endogenous transport activity. Because it is primed for high volume protein synthesis before and following fertilization, the oocyte can readily synthesize membrane proteins from foreign RNAs microinjected into the cytoplasm.

Metal ion transporter and uses therefor

Abstract: The present invention identifies a novel mammalian metal ion transporter with broad substrate specificity. Likely relationships between this transporter and various disorders are described, as are methods of treating the disorders, and of diagnosing individuals susceptible thereto or suffering therefrom.

Disorders of iron metabolism.

Abstract: Iron has the capacity to accept and donate electrons readily, interconverting between ferric (Fe2+) and ferrous (Fe3+) forms. This capability makes it a useful component of cytochromes, oxygen-bind...

Sarcoidosis

Abstract: 结节病易误诊,据王洪武等~([1])收集国内18篇关于此病误诊的文献,误诊率高达63.2%,当然有误诊就会有误治,如孙永昌等~([2])报道26例结节病在影像学检查诊断的第一印象中拟诊结核5例,其中就有2例完成规范的抗结核治疗,为此应引起临床对本病诊治的重视。