Identification of proteins involved in the regulation of yeast iso‐ 1‐cytochrome C expression by oxygen.
Identification of proteins involved in the regulation of yeast iso‐ 1‐cytochrome C expression by oxygen.
复制标题
鉴定参与氧调节酵母 iso-1-细胞色素 C 表达的蛋白质。
作者：
B. Arcangioli;B. Lescure
在凝胶电泳阻滞试验的基础上，通过肝素超凝胶色谱法鉴定并分离与酵母异1-细胞色素C（CYC 1）基因上游激活位点（UASc）特异性相互作用的蛋白质。DNA酶I保护实验表明，这些因子保护了与先前定义的UASc位点重叠的23 bp序列。在厌氧生长的野生型菌株制备的提取物中，特异性结合活性显著降低。在血红素生物合成受阻的突变株中不存在，但在向生长培养基中添加缺失的前体δ氨基乙酰丙酸（dALA）后恢复。相比之下，在葡萄糖或甘油作为碳源中生长的野生型菌株的提取物中，结合活性没有显著差异。这些数据有力地证明，我们已经鉴定的CYC 1 UAS结合蛋白介导细胞色素C生物合成的氧和血红素控制。
On the basis of a gel electrophoresis retardation assay, protein(s) which interact specifically with the upstream activating site (UASc) of the yeast iso‐1‐cytochrome C (CYC1) gene were identified and separated by heparin ultrogel chromatography. DNase I protection experiments indicate that these factors protect a 23‐bp sequence overlapping the UASc site previously defined. The specific binding activity is strongly reduced in extracts prepared from a wild‐type strain grown anaerobically. It is absent in a mutant strain blocked in the biosynthesis of heme but it is restored upon the addition of the missing precursor, delta amino levulinic acid (dALA) to the growth medium. In contrast, the binding activity does not differ significantly in extracts form a wild‐type strain grown in either glucose or glycerol as carbon source. These data strongly argue that the CYC1 UAS binding protein(s) that we have identified mediate the oxygen and heme control of cytochrome C biosynthesis.