Ferroportin and iron export from the macrophage

描述（由申请人提供）： 此申请是为了进一步培训候选人，米切尔克努森，谁拥有博士学位。在营养学和博士后经验，在铁代谢的分子生物学。Knutson博士的近期职业目标是获得新的技能和知识，使他能够研究巨噬细胞中的铁代谢。为了完成这项任务，Knutson博士将接受哈佛公共卫生学院（HSPH）巨噬细胞生物学专家Lester Kobzik博士的指导，并由他目前在HSPH的导师Marianne Wessling-Resnick博士共同指导。该研究计划将研究新鉴定的蛋白质，ferroportin，FPN 1（也称为MTP 1或IREG 1）在巨噬细胞铁代谢中的功能。待检验的假设是FPN 1在吞噬红细胞后从巨噬细胞输出铁中起作用。巨噬细胞吞噬红细胞，随后将铁释放到循环中，构成体内最大的铁通量。然而，其机制尚不清楚。为了研究FPN 1在巨噬细胞中的作用，免疫荧光实验将确定该蛋白的亚细胞定位。将在红细胞吞噬作用前后评估细胞定位。将在红细胞吞噬作用后测量FPN 1 mRNA和蛋白质表达，并将这些变化与铁释放速率的变化进行比较，如通过吞噬59 Fe标记的红细胞后59 Fe的流出所测量的。为了检验FPN 1在铁释放中起作用的假设，将在使用逆转录病毒载体转导在巨噬细胞中过表达FPN 1后以及在使用反义技术抑制FPN 1后测量红细胞来源的59 Fe的流出。HSPH的巨噬细胞生物学，逆转录病毒转导和反义技术专家的接近，结合铁领域研究人员的本地专业知识，为Knutson博士提供了一个非常合适的环境，以学习进行拟议实验所需的必要技能。这些实验的成功完成将大大有助于我们对巨噬细胞中铁代谢的理解，并使Knutson博士能够朝着成为独立研究者和营养学助理教授的长期职业目标前进。此外，更好地了解铁从巨噬细胞释放是相当重要的临床意义，在巨噬细胞铁代谢的特点遗传性血色素沉着症和慢性疾病贫血的障碍。

DESCRIPTION (provided by applicant): This application is for further training of the candidate, Mitchell Knutson, who has a Ph.D. in Nutrition and post-doctoral experience in the molecular biology of iron metabolism. Dr. Knutson's immediate career goal is to acquire new skills and knowledge that will enable him to study iron metabolism in macrophages. To accomplish this task, Dr. Knutson will be mentored by Dr. Lester Kobzik, an expert in macrophage biology at the Harvard School of Public Health (HSPH), and co-mentored by Dr. Marianne Wessling-Resnick, his current mentor at HSPH. The research proposal will investigate the function of the newly identified protein, ferroportin, FPN1 (also known as MTP1 or IREG1), in iron metabolism in the macrophage. The hypothesis to be tested is that FPN1 plays a role in iron export from the macrophage after phagocytosis of red blood cells. Erythrophagocytosis by macrophages, with the subsequent release of iron into the circulation, constitutes the largest flux of iron within the body. The mechanism for this, however, is unknown. To investigate the role of FPN1 in the macrophage, immunofluorescence experiments will determine the subcellular localization of this protein. Cytolocalization will be assessed before and after erythrophagocytosis. FPN1 mRNA and protein expression will be measured after erythrophagocytosis, and the changes will be compared to changes in rates of iron release, as measured by the efflux of 59Fe after phagocytosis of 59Fe-labeled erythrocytes. To test the hypothesis that FPN1 plays a role in iron release, efflux of erythrocyte-derived 59Fe will be measured after overexpressing FPN1 in macrophages using retroviral vector transduction, as well as after suppressing FPN1 using antisense techniques. The proximity of experts in macrophage biology, retroviral transduction, and antisense technology at HSPH, combined with the local expertise of investigators in the iron field, offers Dr. Knutson a highly suitable environment for learning the necessary skills required to carry out the proposed experiments. Successful completion of these experiments will contribute significantly to our understanding of iron metabolism in the macrophage and will enable Dr. Knutson to advance towards his long-term career goal of becoming an independent investigator and Assistant Professor of Nutrition. Moreover, a better understanding of iron release from the macrophage is of considerable clinical importance given the disturbances in macrophage iron metabolism characteristic of hereditary hemochromatosis and the anemia of chronic disease.