2:Regulation of Metallothionein Gene Expression
2:Regulation of Metallothionein Gene Expression
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2：金属硫蛋白基因表达的调控
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
W. Schaffner
中科院分区：
文献类型：
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作者：
K. Balamurugan;W. Schaffner
从细菌到人类的生物体使用复杂的系统来调节生物可利用的锌，铜和其他必需金属的水平。过量的它们，甚至微量的非必需金属，如镉和汞，都可能是剧毒的。金属硫蛋白（MTs）是一种富含半胱氨酸的短蛋白质，在金属稳态和解毒中起着关键作用。它们的巯基可以与有毒金属结合，并在细胞氧化还原平衡和自由基清除中发挥作用。MT的细胞内浓度主要通过调节转录来调节细胞需求。特别是在重金属负荷下，金属硫蛋白基因的转录被强烈诱导。从昆虫到哺乳动物，MT转录的主要调节因子是MTF-1（金属应答转录因子1），它是一种锌指蛋白，与MT基因和其他金属调节基因启动子中的特异性DNA序列基序（MRE）结合。本章提供了一个概述，我们目前的知识MT基因在高等真核生物中的表达和调控，也有一些参考真菌显然已经独立地发展自己的监管系统。
Organisms from bacteria to humans use elaborate systems to regulate levels of bioavailable zinc, copper, and other essential metals. An excess of them, or even traces of non-essential metals such as cadmium and mercury, can be highly toxic. Metallothioneins (MTs), short, cysteine-rich proteins, play pivotal roles in metal homeostasis and detoxification. With their sulfhydryl groups they avidly bind toxic metals and also play a role in cellular redox balance and radical scavenging. The intracellular concentration of MTs is adjusted to cellular demand primarily via regulated transcription. Especially upon heavy metal load, metallothionein gene transcription is strongly induced. From insects to mammals, the major regulator of MT transcription is MTF-1 (metal-responsive transcription factor 1), a zinc finger protein that binds to specific DNA sequence motifs (MREs) in the promoters of MT genes and other metal-regulated genes. This chapter provides an overview of our current knowledge on the expression and regulation of MT genes in higher eukaryotes, with some reference also to fungi which apparently have independently evolved their own regulatory systems.