Abstract
A mutant producing very high levels of the acetamidase enzyme encoded by the amdS gene has been isolated in a strain containing the amdA7 mutation, which itself causes high levels of this enzyme. Genetic analysis has shown that this mutation, designated amdI66, is adjacent to the amdS gene and is cis-dominant in its effect. The amdI66 mutation has little effect on amdS expression when present in strains not containing the amdA7 mutation. Two other amdA mutations investigated also interact with the amdI66 mutation to result in high acetamidase levels. No interaction between amdI66 and any of the other putative regulatory genes affecting amdS expression has been observed. The amdI66 mutation has been located by fine structure mapping at the extreme end of the controlling region, which has previously been defined by genetic mapping (Hynes 1979). Analysis of this region has been extended by mapping new mutations resulting in loss of amdS expression. One of these defines the most extreme site capable of mutation to loss of gene function found so far.
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Selected References
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- Arst H. N., Jr, Rand K. N., Bailey C. R. Do the tightly linked structural genes for nitrate and nitrite reductases in Aspergillus nidulans form an operon? Evidence from an insertional translocation which separates them. Mol Gen Genet. 1979 Jul 2;174(1):89–100. doi: 10.1007/BF00433309. [DOI] [PubMed] [Google Scholar]
- Cove D. J. The induction and repression of nitrate reductase in the fungus Aspergillus nidulans. Biochim Biophys Acta. 1966 Jan 11;113(1):51–56. doi: 10.1016/s0926-6593(66)80120-0. [DOI] [PubMed] [Google Scholar]
- Hynes M. J. A mutation, adjacent to gene amdS, defining the site of action of positive-control gene amdR in Aspergillus nidulans. J Bacteriol. 1980 May;142(2):400–406. doi: 10.1128/jb.142.2.400-406.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hynes M. J. Fine-structure mapping of the acetamidase structural gene and its controlling region in Aspergillus nidulans. Genetics. 1979 Mar;91(3):381–392. doi: 10.1093/genetics/91.3.381. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hynes M. J. Induction of the acetamidase of Aspergillus nidulans by acetate metabolism. J Bacteriol. 1977 Sep;131(3):770–775. doi: 10.1128/jb.131.3.770-775.1977. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hynes M. J. Mutants with altered glucose repression of amidase enzymes in Aspergillus nidulans. J Bacteriol. 1972 Sep;111(3):717–722. doi: 10.1128/jb.111.3.717-722.1972. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hynes M. J., Pateman J. A. The genetic analysis of regulation of amidase synthesis in Aspergillus nidulans. I. Mutants able to utilize acrylamide. Mol Gen Genet. 1970;108(2):97–106. doi: 10.1007/BF02430516. [DOI] [PubMed] [Google Scholar]
- McKnight G. L., Cardillo T. S., Sherman F. An extensive deletion causing overproduction of yeast iso-2-cytochrome c. Cell. 1981 Aug;25(2):409–419. doi: 10.1016/0092-8674(81)90059-3. [DOI] [PubMed] [Google Scholar]
- Sherman F., Helms C. A chromosomal translocation causing overproduction of iso-2-cytochrome c in yeast. Genetics. 1978 Apr;88(4 Pt 1):689–707. [PMC free article] [PubMed] [Google Scholar]