The zinc finger protein ZNF658 regulates the transcription of genes involved in zinc homeostasis and affects ribosome biogenesis through the zinc transcriptional regulatory element.
The zinc finger protein ZNF658 regulates the transcription of genes involved in zinc homeostasis and affects ribosome biogenesis through the zinc transcriptional regulatory element.
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DOI：
10.1128/mcb.01298-14
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发表时间：
2015-03
影响因子：
5.3
通讯作者：
Ford D
中科院分区：
文献类型：
--
作者：
Ogo OA;Tyson J;Cockell SJ;Howard A;Valentine RA;Ford D
我们以前在参与锌稳态的基因中发现了锌转录调节元件(ZTRE)，并表明它介导了锌反应的转录抑制。我们现在报告ZNF658在ZTRE发挥作用。ZNF658经基质辅助激光解吸电离飞行时间质谱仪鉴定。该蛋白含有一个KRAB结构域和21个锌指。它与酿酒酵母中调控锌限制反应的ZAP1有相似之处，包括一个保守的DNA结合区，我们在ZNF658中也发现了功能。针对ZNF658的小干扰RNA(SiRNA)阻断了锌诱导的人Caco-2细胞SLC30A5(ZnT5基因)、SLC30A10(ZnT10基因)和CBWD转录本的ZTRE依赖性减少，以及锌抑制相应启动子-报告结构报告基因表达的能力。对siRNA降低ZNF658表达效果的微阵列分析发现，rRNA大幅下降。我们发现ZTRE聚集在45S rRNA前体中。我们还看到了对多种核糖体蛋白表达的影响。因此，ZNF658将锌的动态平衡与核糖体的生物发生联系起来，核糖体的生物发生是细胞中最活跃的转录过程，因此也是对锌的需求过程。因此，ZNF658是一种新的转录调控因子，在细胞对锌可利用性的协调反应中发挥着重要作用。
We previously identified the ZTRE (zinc transcriptional regulatory element) in genes involved in zinc homeostasis and showed that it mediates transcriptional repression in response to zinc. We now report that ZNF658 acts at the ZTRE. ZNF658 was identified by matrix-assisted laser desorption ionization–time of flight mass spectrometry of a band excised after electrophoretic mobility shift assay using a ZTRE probe. The protein contains a KRAB domain and 21 zinc fingers. It has similarity with ZAP1 from Saccharomyces cerevisiae, which regulates the response to zinc restriction, including a conserved DNA binding region we show to be functional also in ZNF658. Small interfering RNA (siRNA) targeted to ZNF658 abrogated the zinc-induced, ZTRE-dependent reduction in SLC30A5 (ZnT5 gene), SLC30A10 (ZnT10 gene), and CBWD transcripts in human Caco-2 cells and the ability of zinc to repress reporter gene expression from corresponding promoter-reporter constructs. Microarray analysis of the effect of reducing ZNF658 expression by siRNA uncovered a large decrease in rRNA. We find that ZTREs are clustered within the 45S rRNA precursor. We also saw effects on expression of multiple ribosomal proteins. ZNF658 thus links zinc homeostasis with ribosome biogenesis, the most active transcriptional, and hence zinc-demanding, process in the cell. ZNF658 is thus a novel transcriptional regulator that plays a fundamental role in the orchestrated cellular response to zinc availability.