Expression of Rgmc, the murine ortholog of hemojuvelin gene, is modulated by development and inflammation, but not by iron status or erythropoietin.
Mutations of hepcidin (HAMP) and hemo-juvelin (HJV) genes have been recently demonstrated to result in juvenile hemochromatosis. Expression of HAMP is regulated by iron status or infection, whereas regulation of HJV is yet unknown. Using quantitative real-time polymerase chain reaction, we compared expression of Hamp and Rgmc (the murine ortholog of HJV) in livers of mice treated with iron, erythropoietin, or lipopolysaccharide (LPS), as well as during fetal and postnatal development. Iron overload increased Hamp expression without effect on Rgmc mRNA. Erythropoietin decreased Hamp mRNA, but Rgmc expression was unchanged. Hamp mRNA level decreased after birth by 4 orders of magnitude, without significant changes in Rgmc expression. Administration of LPS elevated Hamp mRNA levels, while markedly decreasing hepatic Rgmc mRNA levels (to approximately 5% after 6 hours). The responses of Hamp and Rgmc were quite different and suggested that human HJV expression could be modulated by inflammation.
Institute of Pathological Physiology, First Faculty of Medicine, Charles University, U nemocnice 5, 128 53 Prague, Czech Republic. jkri@lf1.cuni.cz
Jan
J
Krijt
Martin
M
Vokurka
Ko-Tung
KT
Chang
Emanuel
E
Necas
D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000235:genetics; D004921:Erythropoietin / Q000494:pharmacology*; D058851:GPI-Linked Proteins; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects / Q000235:genetics*; D064451:Hepcidins; D006706:Homeostasis; D007249:Inflammation / Q000503:physiopathology; D007501:Iron / Q000378:metabolism*; D008099:Liver / Q000196:embryology / Q000254:growth & development; D051379:Mice; D009124:Muscle Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000071020:Hemochromatosis Protein
D023181:Antimicrobial Cationic Peptides; D004921:Erythropoietin; D058851:GPI-Linked Proteins; D064451:Hepcidins; D007501:Iron; D009124:Muscle Proteins; D012333:RNA, Messenger; C578702:HAMP protein, human; C579599:Hamp protein, mouse; C504414:HJV protein, mouse; D000071020:Hemochromatosis Protein