Multicopper oxidase-1 is required for iron homeostasis in Malpighian tubules of Helicoverpa armigera
Multicopper oxidase-1 is required for iron homeostasis in Malpighian tubules of Helicoverpa armigera
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DOI：
10.1038/srep14784
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发表时间：
2015-10
影响因子：
4.6
通讯作者：
Xiaoming Liu;Chengxian Sun;X. Liu;Xinming Yin;Baohai Wang;M. Du;S. An
中科院分区：
文献类型：
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作者：
Xiaoming Liu;Chengxian Sun;X. Liu;Xinming Yin;Baohai Wang;M. Du;S. An
多铜氧化酶（MC 0）是含有10个保守的组氨酸残基和1个半胱氨酸残基的酶。MCO 1已在中肠中被广泛研究，因为该MCO与抗坏血酸氧化、铁稳态和免疫反应有关。然而，关于MCO 1在马氏管中作用的信息有限。本研究以棉铃虫为模型，探讨马氏管MCO 1的功能。序列分析结果显示HaMCO 1具有典型的MCO特征，含有10个组氨酸和1个半胱氨酸残基，用于铜离子结合。HaMCO 1也被发现是高度丰富的马氏管。时间表达模式表明HaMCO 1主要在幼虫蜕皮阶段表达。激素处理[蜕皮激素20-羟基蜕皮激素（20 E）和保幼激素（JH）]显示，20 E通过其异二聚体受体（由蜕皮激素受体（EcR）和超气门（USP）组成）抑制HaMCO 1转录本表达，JH通过其细胞内受体甲氧普烯耐受（Met）抵消20 E激活HaMCO 1转录本表达的作用。HaMCO 1敲低导致铁积累显著减少，也显著降低转铁蛋白和铁蛋白转录本表达。因此，HaMCO 1是协调调节20 E和JH和所需的铁稳态马氏管。
Multicopper oxidases (MCOs) are enzymes that contain 10 conserved histidine residues and 1 cysteine residue. MCO1 has been extensively investigated in the midgut because this MCO is implicated in ascorbate oxidation, iron homeostasis and immune responses. However, information regarding the action of MCO1 in Malpighian tubules is limited. In this study, Helicoverpa armigera was used as a model to investigate the function of MCO1 in Malpighian tubules. Sequence analysis results revealed that HaMCO1 exhibits typical MCO characteristics, with 10 histidine and 1 cysteine residues for copper ion binding. HaMCO1 was also found to be highly abundant in Malpighian tubules. Temporal expression patterns indicated that HaMCO1 is mainly expressed during larval molting stages. Hormone treatments [the molting hormone 20-hydroxyecdysone (20E) and juvenile hormone (JH)] revealed that 20E inhibits HaMCO1 transcript expression via its heterodimer receptor, which consists of ecdysone receptor (EcR) and ultraspiracle (USP) and that JH counteracts the action of 20E to activate HaMCO1 transcript expression via its intracellular receptor methoprene-tolerant (Met). HaMCO1 knockdown caused a significant decrease in iron accumulation and also significantly reduced transferrin and ferritin transcript expression. Therefore, HaMCO1 is coordinately regulated by 20E and JH and is required for iron homeostasis in Malpighian tubules.