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The uaY positive control gene of Aspergillus nidulans: fine structure, isolation of constitutive mutants and reversion patterns

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The product of the uaY gene of Aspergillus nidulans is necessary for the expression of at least eight genes coding for enzymes and permeases of the purine utilisation pathway. A detailed fine structure map has been constructed of this gene involving 13 presumed point mutations and eight deletions. Gene conversion of these deletions was demonstrated. A technique was devised to select for constitutive mutations and two were obtained which map within the uaY gene. We have shown that the most centromere proximal allele reverts to a number of different phenotypes. The properties of this allele suggest that it may map in the open reading frame of the uaY gene, in a domain that could be altered in a way that would differentially affect the expression of genes under uaY control.

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Communicated by W. Gajewski

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Suárez, T., Oestreicher, N., Kelly, J. et al. The uaY positive control gene of Aspergillus nidulans: fine structure, isolation of constitutive mutants and reversion patterns. Molec. Gen. Genet. 230, 359–368 (1991).

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