Fep1 represses expression of the fission yeast Schizosaccharomyces pombe siderophore-iron transport system
Fep1 represses expression of the fission yeast Schizosaccharomyces pombe siderophore-iron transport system
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DOI：
10.1093/nar/gkg647
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发表时间：
2003-08-01
影响因子：
14.9
通讯作者：
Labbé, S
中科院分区：
文献类型：
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作者：
Pelletier, B;Beaudoin, J;Labbé, S
当铁充足时，粟酒裂殖酵母细胞会抑制编码参与还原性铁转运系统的成分的基因的转录。 Fep1 通过与 GATA 型顺式作用元件特异性相互作用来介导这种转录控制。为了进一步研究 Fep1 在铁稳态中的作用，我们寻找了其他 Fep1 调节的基因。我们发现str1(+)受到负转录调控，这是通过Fep1与str1(+)启动子中的单个GATA元件结合来实现的。将 str1(+) 引入酿酒酵母 fet3Delta arn1-4Delta 菌株中，导致铁色素中铁的同化，表明 Str1 在粟酒裂殖酵母中充当铁载体-铁转运蛋白。我们还鉴定了 Fep1 的另外两个靶基因，名为 str2(+) 和 str3(+)。我们证明 str1(+)、str2(+) 和 str3(+) 基因共享一个共同的启动子元件 5'-(A/T)GATAA-3'。我们发现大肠杆菌中表达的 Fep1 N 端 241 残基片段与这些启动子中存在的 5'-(A/T)GATAA-3' 元件特异性相互作用。与此一致的是，在 fep1Delta 突变株中观察到了 str1(+)、str2(+) 和 str3(+) 基因的组成型高水平表达。总而言之，这些结果表明 Fep1 在协调裂殖酵母中还原性和非还原性铁转运系统成分的基因转录调控中发挥着核心作用。
When iron repletes, Schizosaccharomyces pombe cells repress transcription of genes encoding components involved in the reductive iron transport system. Fep1 mediates this transcriptional control by interacting specifically with GATA-type cis-acting elements. To further investigate the role that Fep1 plays in iron homeostasis, we searched for additional Fep1-regulated genes. We found that str1(+) is subject to negative transcriptional regulation, which is exerted through binding of Fep1 to a single GATA element in the str1(+) promoter. Introduction of str1(+) into a Saccharomyces cerevisiae fet3Delta arn1-4Delta strain led to assimilation of iron from ferrichrome, revealing that Str1 functions as a siderophore-iron transporter in S.pombe. We also identified two additional target genes of Fep1, named str2(+) and str3(+). We demonstrate that the str1(+), str2(+) and str3(+) genes share a common promoter element, 5'-(A/T)GATAA-3'. We found that the N-terminal 241 residue segment of Fep1 expressed in Escherichia coli specifically interacts with the 5'-(A/T)GATAA-3' element present in each of these promoters. Consistent with this, constitutive high level str1(+), str2(+) and str3(+) gene expression was observed in a fep1Delta mutant strain. Taken together, these results demonstrate that Fep1 occupies a central role in coordinating transcriptional regulation of genes encoding components of the reductive and non-reductive iron transport systems in fission yeast.