| RRC ID |
38183
|
| 著者 |
Kono S, Yoshida K, Tomosugi N, Terada T, Hamaya Y, Kanaoka S, Miyajima H.
|
| タイトル |
Biological effects of mutant ceruloplasmin on hepcidin-mediated internalization of ferroportin.
|
| ジャーナル |
Biochim Biophys Acta
|
| Abstract |
Ceruloplasmin plays an essential role in cellular iron efflux by oxidizing ferrous iron exported from ferroportin. Ferroportin is posttranslationally regulated through internalization triggered by hepcidin binding. Aceruloplasminemia is an autosomal recessive disorder of iron homeostasis resulting from mutations in the ceruloplasmin gene. The present study investigated the biological effects of glycosylphosphatidylinositol (GPI)-linked ceruloplasmin on the hepcidin-mediated internalization of ferroportin. The prevention of hepcidin-mediated ferroportin internalization was observed in the glioma cells lines expressing endogenous ceruloplasmin as well as in the cells transfected with GPI-linked ceruloplasmin under low levels of hepcidin. A decrease in the extracellular ferrous iron by an iron chelator and incubation with purified ceruloplasmin in the culture medium prevented hepcidin-mediated ferroportin internalization, while the reconstitution of apo-ceruloplasmin was not able to prevent ferroportin internalization. The effect of ceruloplasmin on the ferroportin stability was impaired due to three distinct properties of the mutant ceruloplasmin: namely, a decreased ferroxidase activity, the mislocalization in the endoplasmic reticulum, and the failure of copper incorporation into apo-ceruloplasmin. Patients with aceruloplasminemia exhibited low serum hepcidin levels and a decreased ferroportin protein expression in the liver. The in vivo findings supported the notion that under low levels of hepcidin, mutant ceruloplasmin cannot stabilize ferroportin because of a loss-of-function in the ferroxidase activity, which has been reported to play an important role in the stability of ferroportin. The properties of mutant ceruloplasmin regarding the regulation of ferroportin may therefore provide a therapeutic strategy for aceruloplasminemia patients.
|
| 巻・号 |
1802(11)
|
| ページ |
968-75
|
| 公開日 |
2010-11-1
|
| DOI |
10.1016/j.bbadis.2010.07.011
|
| PII |
S0925-4439(10)00148-1
|
| PMID |
20655381
|
| MeSH |
Antimicrobial Cationic Peptides / blood
Antimicrobial Cationic Peptides / metabolism*
Antimicrobial Cationic Peptides / pharmacology
Blotting, Western
Cation Transport Proteins / metabolism*
Cell Line, Tumor
Ceruloplasmin / genetics
Ceruloplasmin / metabolism*
Dose-Response Relationship, Drug
Endocytosis / drug effects
Female
Gene Expression Profiling
Glycosylphosphatidylinositols / metabolism
HeLa Cells
Hepcidins
Humans
Iron Metabolism Disorders / blood
Iron Metabolism Disorders / genetics
Iron Metabolism Disorders / metabolism
Liver / metabolism
Male
Mutation*
Reverse Transcriptase Polymerase Chain Reaction
Transfection
|
| IF |
3.411
|
| 引用数 |
51
|
|
WOS 分野
|
BIOPHYSICS
BIOCHEMISTRY & MOLECULAR BIOLOGY
CELL BIOLOGY
|
| リソース情報 |
| ヒト・動物細胞 |
C6(RCB2854)
U251(RCB0461) |
