Functional analysis and theoretical modeling of ferroportin reveals clustering of mutations according to phenotype

被引:66
作者
Wallace, Daniel F. [1 ]
Harris, Jonathan M. [2 ]
Subramaniam, V. Nathan [1 ]
机构
[1] Queensland Inst Med Res, Membrane Transport Lab, Brisbane, Qld 4006, Australia
[2] Queensland Univ Technol, Inst Hlth & Biomed Innovat, Brisbane, Qld 4001, Australia
来源
AMERICAN JOURNAL OF PHYSIOLOGY-CELL PHYSIOLOGY | 2010年 / 298卷 / 01期
基金
澳大利亚国家健康与医学研究理事会; 英国医学研究理事会;
关键词
iron; hemochromatosis; ferritin; hepcidin; IRON OVERLOAD; HEPCIDIN; HEMOCHROMATOSIS; TRANSPORTER; SLC11A3; BINDING;
D O I
10.1152/ajpcell.00621.2008
中图分类号
Q2 [细胞生物学];
学科分类号
071009 ; 090102 ;
摘要
Wallace DF, Harris JM, Subramaniam VN. Functional analysis and theoretical modeling of ferroportin reveals clustering of mutations according to phenotype. Am J Physiol Cell Physiol 298: C75-C84, 2010. First published October 21, 2009; doi:10.1152/ajpcell.00621.2008.-Ferroportin disease is a heterogeneous iron release disorder resulting from mutations in the ferroportin gene. Ferroportin protein is a multitransmembrane domain iron transporter, responsible for iron export from cells, which, in turn, is regulated by the peptide hormone hepcidin. Mutations in the ferroportin gene may affect either regulation of the protein's transporter function or the ability of hepcidin to regulate iron efflux. We have used a combination of functional analysis of epitope-tagged ferroportin variants coupled with theoretical modeling to dissect the relationship between ferroportin mutations and their cognate phenotypes. Myc epitope-tagged human ferroportin expression constructs were transfected into Caco-2 intestinal cells and protein localization analyzed by immunofluorescence microscopy and colocalization with organelle markers. The effect of mutations on iron efflux was assessed by costaining with anti-ferritin antibodies and immunoblotting to quantitate cellular expression of ferritin and transferrin receptor 1. Wild-type ferroportin localized mainly to the cell surface and intracellular structures. All ferroportin disease-causing mutations studied had no effect on localization at the cell surface. N144H, N144T, and S338R mutant ferroportin retained the ability to transport iron. In contrast, A77D, V162 Delta, and L170F mutants were iron transport defective. Surface staining experiments showed that both ends of the protein were located inside the cell. These data were used as the basis for theoretical modeling of the ferroportin molecule. The model predicted phenotypic clustering of mutations with gain-of-function variants associated with a hypothetical channel through the axis of ferroportin. Conversely, loss-of-function variants were located at the membrane/cytoplasm interface.
引用
收藏
页码:C75 / C84
页数:10
相关论文
共 37 条
  • [1] A novel mammalian iron-regulated protein involved in intracellular iron metabolism
    Abboud, S
    Haile, DJ
    [J]. JOURNAL OF BIOLOGICAL CHEMISTRY, 2000, 275 (26) : 19906 - 19912
  • [2] A novel mutation in ferroportin1 is associated with haemochromatosis in a Solomon Islands patient
    Arden, KE
    Wallace, DF
    Dixon, JL
    Summerville, L
    Searle, JW
    Anderson, GJ
    Ramm, GA
    Powell, LW
    Subramaniam, VN
    [J]. GUT, 2003, 52 (08) : 1215 - 1217
  • [3] Evidence for differential effects of hepcidin in macrophages and intestinal epithelial cells
    Chaston, T.
    Chung, B.
    Mascarenhas, M.
    Marks, J.
    Patel, B.
    Srai, S. K.
    Sharp, P.
    [J]. GUT, 2008, 57 (03) : 374 - 382
  • [4] The molecular basis of ferroportin-linked hemochromatosis
    De Domenico, I
    Ward, DM
    Nemeth, E
    Vaughn, MB
    Musci, G
    Ganz, T
    Kaplan, J
    [J]. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2005, 102 (25) : 8955 - 8960
  • [5] RETRACTED: The hepcidin-binding site on ferroportin is evolutionarily conserved (Retracted article. See vol. 19, pg. 1067, 2014)
    De Domenico, Ivana
    Nemeth, Elizabeta
    Nelson, Jenifer M.
    PhillipS, John D.
    Ajioka, Richard S.
    Kay, Michael S.
    Kushner, James P.
    Ganz, Tomas
    Ward, Diane M.
    Kaplan, Jerry
    [J]. CELL METABOLISM, 2008, 8 (02) : 146 - 156
  • [6] De Domenico I, 2007, MOL BIOL CELL, V18, P2569, DOI 10.1091/mbc.E07-01-0060
  • [7] Evidence for the multimeric structure of ferroportin
    De Domenico, Ivana
    Ward, Diane McVey
    Musci, Giovanni
    Kaplan, Jerry
    [J]. BLOOD, 2007, 109 (05) : 2205 - 2209
  • [8] De Domenico I, 2006, HAEMATOLOGICA, V91, P92
  • [9] Autosomal dominant reticuloendothelial iron overload associated with a 3-base pair deletion in the ferroportin 1 gene (SLC11A3)
    Devalia, V
    Carter, K
    Walker, AP
    Perkins, SJ
    Worwood, M
    May, A
    Dooley, JS
    [J]. BLOOD, 2002, 100 (02) : 695 - 697
  • [10] Positional cloning of zebrafish ferroportin1 identifies a conserved vertebrate iron exporter
    Donovan, A
    Brownlie, A
    Zhou, Y
    Shepard, J
    Pratt, SJ
    Moynihan, J
    Paw, BH
    Drejer, A
    Barut, B
    Zapata, A
    Law, TC
    Brugnara, C
    Kingsley, PD
    Palis, J
    Fleming, MD
    Andrews, NC
    Zon, LI
    [J]. NATURE, 2000, 403 (6771) : 776 - 781