Molecular Mechanism of the Metallothionein Gene Expression Mediated by Metal-Responsive Transcription Factor 1
نویسنده
چکیده
Metal-responsive transcription factor 1 (MTF-1) is essential for activating transcription of the metallothionein genes in response to multiple species of heavy metals by binding to the metal-responsive element (MRE) located in the upstream region of the genes. In contrast, MTF-1 binding to the MRE in vitro is induced only by zinc ions, suggesting that MTF-1 acts as a zinc sensor protein. Although the mechanism allowing such a zinc-responsive factor to respond to various metal species in vivo remains ambiguous, recent information regarding the metal response of MTF-1 and the genes expressed downstream of MTF-1 provides important clues to unraveling the intrinsic mechanism and the biological significance of the MTF-1 functions in vivo.
منابع مشابه
Activity of metal-responsive transcription factor 1 by toxic heavy metals and H2O2 in vitro is modulated by metallothionein.
Metallothioneins are small, cysteine-rich proteins that avidly bind heavy metals such as zinc, copper, and cadmium to reduce their concentration to a physiological or nontoxic level. Metallothionein gene transcription is induced by several stimuli, notably heavy metal load and oxidative stress. Transcriptional induction of metallothionein genes is mediated by the metal-responsive transcription ...
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Metallothioneins are small, cysteine-rich, metal-binding proteins that play important roles in maintaining intracellular metal homeostasis and in transition metal detoxification. MTF-1 (metal transcription factor-1) plays a central role in regulating the metal-inducible, transcriptional activation of metallothionein. Here we report that the phosphorylation of MTF-1 plays a critical role in the ...
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Mammalian metallothionein (MT) genes are transcriptionally activated by the essential metal zinc as well as by environmental stresses, including toxic metal overload and redox fluctuations. In addition to playing a key role in zinc homeostasis, MT proteins can protect against metaland oxidant-induced cellular damage, and may participate in other fundamental physiologic and pathologic processes ...
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