Ogawa N, Noguchi K, Yamashita Y, Yasuhara T, Hayashi N, Yoshida K, Oshima Y
Department of Biotechnology, Faculty of Engineering, Osaka University, Japan.
Mol Gen Genet. 1993 Apr;238(3):444-54. doi: 10.1007/BF00292004.
The PHO81 gene encoding one of the regulators of the phosphatase regulon in Saccharomyces cerevisiae was mapped 9.8 centimorgans distal from the ser2 locus on the right arm of chromosome VII. Determination of the nucleotide sequence of cloned PHO81 DNA revealed a 3537 bp open reading frame encoding a 134 kDa protein. This protein has six repeats of a 33-amino acid sequence homologous to the ankyrin repeat and an asparagine-rich region. Transcription of PHO81 is activated by Pho4 protein in cooperation with Pho2 (i.e., Bas2/Grf10) protein under the influence of the inorganic phosphate (Pi) concentration in the medium, through the PHO regulatory system. Major transcription initiation sites of PHO81, determined by primer extension analysis, are at nucleotide positions -66 and -65 relative to the ATG codon. Deletion analysis showed that a 95 bp region from nucleotide position -385 to -291 is essential for response to the Pi signals. Purified Pho4 protein protected a 19 bp region (positions -350 to -332) in the 95 bp fragment from DNase I digestion in vitro and the protected region includes the core sequence 5'-CACGTG-3', which is also observed in other genes of phosphate metabolism.
编码酿酒酵母中磷酸酶调节子的调节因子之一的PHO81基因，被定位在第七条染色体右臂上ser2基因座远端9.8厘摩处。对克隆的PHO81 DNA核苷酸序列的测定揭示了一个3537 bp的开放阅读框，编码一种134 kDa的蛋白质。该蛋白质具有六个与锚蛋白重复序列同源的33个氨基酸序列的重复序列以及一个富含天冬酰胺的区域。在培养基中无机磷酸盐（Pi）浓度的影响下，PHO81的转录通过PHO调节系统，由Pho4蛋白与Pho2（即Bas2/Grf10）蛋白协同激活。通过引物延伸分析确定的PHO81的主要转录起始位点，相对于ATG密码子位于核苷酸位置-66和-65处。缺失分析表明，从核苷酸位置-385到-291的一个95 bp区域对于对Pi信号的响应至关重要。纯化的Pho4蛋白在体外保护95 bp片段中一个19 bp的区域（位置-350至-332）免受DNase I消化，并且该受保护区域包括核心序列5'-CACGTG-3'，这在其他磷酸盐代谢基因中也有观察到。
