Deckert J, Perini R, Balasubramanian B, Zitomer R S
Department of Biological Sciences, State University of New York at Albany 12222, USA.
Genetics. 1995 Mar;139(3):1149-58. doi: 10.1093/genetics/139.3.1149.
The ROX1 gene encodes a heme-induced repressor of hypoxic genes in yeast. Using RNA blot analysis and a ROX1/lacZ fusion construct that included the ROX1 upstream region and only the first codon, we discovered that Rox1 represses its own expression. Gel-retardation experiments indicated that Rox1 was capable of binding to its own upstream region. Overexpression of Rox1 from the inducible GAL1 promoter was found to be inhibitory to cell growth. Also, we found that, as reported previously, Hap1 is partially responsible for heme-induction of ROX1, but, in addition, it also may play a role in ROX1 repression in the absence of heme. There is a second repressor of anaerobic ROX1 expression that requires the general repressor Tup1/Ssn6 for its function.
ROX1基因编码酵母中一种由血红素诱导的低氧基因阻遏物。利用RNA印迹分析以及一个包含ROX1上游区域且仅含第一个密码子的ROX1/lacZ融合构建体，我们发现Rox1可抑制其自身表达。凝胶阻滞实验表明，Rox1能够结合其自身的上游区域。从可诱导的GAL1启动子过表达Rox1被发现对细胞生长具有抑制作用。此外，我们发现，如先前报道的那样，Hap1部分负责ROX1的血红素诱导，但除此之外，它在无血红素时的ROX1抑制中也可能发挥作用。存在一种厌氧ROX1表达的第二种阻遏物，其功能需要通用阻遏物Tup1/Ssn6。
