School of Biological and Chemical Sciences, Queen Mary, University of London, Mile End Road, London, E1 4NS, UK.
Nutrients. 2013 May 17;5(5):1622-47. doi: 10.3390/nu5051622.
The way in which Drosophila melanogaster acquires iron from the diet remains poorly understood despite iron absorption being of vital significance for larval growth. To describe the process of organismal iron absorption, consideration needs to be given to cellular iron import, storage, export and how intestinal epithelial cells sense and respond to iron availability. Here we review studies on the Divalent Metal Transporter-1 homolog Malvolio (iron import), the recent discovery that Multicopper Oxidase-1 has ferroxidase activity (iron export) and the role of ferritin in the process of iron acquisition (iron storage). We also describe what is known about iron regulation in insect cells. We then draw upon knowledge from mammalian iron homeostasis to identify candidate genes in flies. Questions arise from the lack of conservation in Drosophila for key mammalian players, such as ferroportin, hepcidin and all the components of the hemochromatosis-related pathway. Drosophila and other insects also lack erythropoiesis. Thus, systemic iron regulation is likely to be conveyed by different signaling pathways and tissue requirements. The significance of regulating intestinal iron uptake is inferred from reports linking Drosophila developmental, immune, heat-shock and behavioral responses to iron sequestration.
尽管铁吸收对幼虫生长至关重要，但黑腹果蝇从饮食中获取铁的方式仍知之甚少。为了描述机体铁吸收的过程，需要考虑细胞铁的摄取、储存、输出以及肠上皮细胞如何感知和响应铁的可用性。在这里，我们回顾了二价金属转运蛋白-1 同源物 Malvolio（铁摄取）、最近发现的多铜氧化酶-1 具有亚铁氧化酶活性（铁输出）以及铁蛋白在铁获取过程中的作用（铁储存）的研究。我们还描述了昆虫细胞中铁的调节情况。然后，我们借鉴哺乳动物铁稳态的知识来鉴定果蝇中的候选基因。由于铁蛋白、hepcidin 和与血色素沉着症相关途径的所有成分等关键哺乳动物参与者在果蝇中缺乏保守性，因此出现了问题。果蝇和其他昆虫也没有红细胞生成。因此，系统的铁调节可能通过不同的信号通路和组织需求来传递。从将果蝇发育、免疫、热休克和行为反应与铁螯合联系起来的报告中可以推断出调节肠道铁摄取的重要性。
