镉抗性酵母中金属硫蛋白基因的组成型转录。

Constitutive transcription of the gene for metallothionein in a cadmium-resistant yeast.

作者信息

Tohoyama H, Inagawa A, Koike H, Inouhe M, Joho M, Murayama T

机构信息

Department of Biology, Faculty of Science, Ehime University, Matsuyama, Japan.

出版信息

FEMS Microbiol Lett. 1992 Aug 1;74(1):81-5. doi: 10.1016/0378-1097(92)90740-f.

DOI:10.1016/0378-1097(92)90740-f

PMID:1516810

Abstract

A cadmium-resistant strain of Saccharomyces cerevisiae produces a cadmium metallothionein encoded by the CUP1 gene as does a copper-resistant strain. The mechanism of expression of the gene is inducible by copper ions in the copper-resistant strain. However, assays of CUP1-specific mRNA revealed that the transcription of the CUP1 gene in the cadmium-resistant strain is constitutive and the rate of transcription is further increased by exposure to cadmium or copper ions. This result was confirmed by the appearance of constitutive-expression segregants from diploid crosses between the cadmium-resistant strain and a strain with a reporter gene having the promoter of CUP1.

摘要

一株抗镉的酿酒酵母菌株会产生由CUP1基因编码的镉金属硫蛋白，就如同一株抗铜菌株一样。在抗铜菌株中，该基因的表达机制可被铜离子诱导。然而，对CUP1特异性mRNA的检测显示，在抗镉菌株中CUP1基因的转录是组成型的，并且通过暴露于镉或铜离子，转录速率会进一步提高。通过抗镉菌株与带有具有CUP1启动子的报告基因的菌株之间的二倍体杂交产生的组成型表达分离子的出现，证实了这一结果。