Mechanism of Ferroportin Ubiquitination and its Therapeutic Potential in Anemia of Chronic Disease

铁转运蛋白泛素化机制及其治疗慢性病贫血的潜力

• 批准号: 413746767
• 负责人: Dr. Lisa Schrader
• 金额: --
• 依托单位: Department of Anesthesia, Critical Care and Pain Medicine
• 依托单位国家: 德国
• 项目类别: Research Fellowships
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/413746767?language=en
• 关键词: Mechanism; Ferroportin; Ubiquitination; its; Therapeutic

The hepcidin-ferroportin signaling pathway has an important role in many disorders of iron metabolism, including iron overload syndromes (hemochromatosis) and anemia. Anemia of chronic disease is the second most common form of anemia and is present in conditions associated with infection, malignancy and inflammation. Anemia of chronic disease is characterized by low plasma iron concentrations despite sufficient stores of iron in the bone marrow, liver and spleen. In patients with these conditions, inflammatory cytokines induce expression of the hepatic hormone hepcidin. Hepcidin post-translationally regulates the cell surface expression of the iron exporter ferroportin. Ferroportin is the only membrane channel that is able to export iron from inside cells and thereby regulates the amount of circulating iron. Hepcidin binds to ferroportin and induces its ubiquitination, internalization and lysosomal degradation. As a result, the amount of iron that is available to developing red blood cells decreases. The objectives of the proposed research are to identify the enzymes involved in hepcidin- induced ferroportin ubiquitination and to determine whether inhibition of ferroportin ubiquitination is a potential novel therapy for the treatment of anemia of chronic disease. A cell line that inducible expresses ferroportin fused to green fluorescent protein (GFP) will be used to screen a commercially-available siRNA library that targets individual enzymes that are potentially involved in the transfer of ubiquitin to ferroportin. After identifying the ubiquitin conjugating and ligating enzymes that are involved in the degradation of ferroportin, the effect of siRNA-mediated knockdown of these enzymes on the development of turpentine-induced anemia of chronic disease in mice will be investigated. The host laboratory has established a cell line that expresses inducible ferroportin-GFP and is able to induce the expression of hepcidin by BMP treatment. This allows the analysis of ferroportin degradation under more physiological conditions. In addition, the chief of the host laboratory, Dr. Bloch, has extensive experience in the field of iron homeostasis and the use of murine models of chronic disease. The proposed research program will increase our understanding of iron homeostasis by elucidating the mechanism of ferroportin ubiquitination and degradation. It is anticipated that the results of these studies will permit the development of novel approaches to treat patients with iron-restrictive disorders.

铁调素-膜铁转运蛋白信号通路在许多铁代谢紊乱中具有重要作用，包括铁过载综合征（血色病）和贫血。 慢性病贫血是贫血的第二种最常见的形式，并且存在于与感染、恶性肿瘤和炎症相关的病症中。 慢性贫血的特点是血浆铁浓度低，尽管在骨髓、肝脏和脾脏中储存了足够的铁。在患有这些病症的患者中，炎性细胞因子诱导肝激素铁调素的表达。 铁调素翻译后调节铁输出蛋白ferroportin的细胞表面表达。 铁转运蛋白是唯一能够从细胞内输出铁的膜通道，从而调节循环铁的量。 铁调素结合膜铁转运蛋白并诱导其泛素化、内化和溶酶体降解。 因此，可用于发展红细胞的铁的量减少。本研究的目的是鉴定参与铁调素诱导的膜铁转运蛋白泛素化的酶，并确定抑制膜铁转运蛋白泛素化是否是治疗慢性疾病贫血的潜在新疗法。可诱导表达与绿色荧光蛋白（GFP）融合的膜铁转运蛋白的细胞系将用于筛选可商购的siRNA文库，所述siRNA文库靶向可能参与泛素向膜铁转运蛋白转移的各个酶。在鉴定参与膜铁转运蛋白降解的泛素缀合和连接酶后，将研究siRNA介导的这些酶的敲低对小鼠中松节油诱导的慢性疾病贫血的发展的影响。 宿主实验室已经建立了表达诱导型铁转运蛋白-GFP的细胞系，并且能够通过BMP处理诱导铁调素的表达。这允许在更生理条件下分析膜铁转运蛋白降解。此外，主实验室主任Bloch博士在铁稳态和慢性疾病小鼠模型的使用领域拥有丰富的经验。该研究计划将通过阐明膜铁转运蛋白泛素化和降解的机制来增加我们对铁稳态的理解。 预计这些研究的结果将允许开发新的方法来治疗铁限制性疾病患者。

项目成果

HFE and ALK3 act in the same signaling pathway.

• DOI: 10.1016/j.freeradbiomed.2020.08.023
• 发表时间: 2020-08
• 期刊: Free radical biology & medicine
• 影响因子: 7.4
• 作者: L. Traeger;J. Schnittker;D. Y. Dogan;D. Oguama;T. Kuhlmann;M. Muckenthaler;J. Krijt;E. Urzica;A. Steinbicker