Lockington R A, Sealy-Lewis H M, Scazzocchio C, Davies R W
Gene. 1985;33(2):137-49. doi: 10.1016/0378-1119(85)90088-5.
In Aspergillus nidulans alcohol dehydrogenase (ADH) I and aldehyde dehydrogenase (AldDH) are co-inducible by acetaldehyde (Pateman et al., 1983; Sealy-Lewis and Lockington, 1984) and subject to carbon catabolite repression. The structural genes alcA and aldA are unlinked, but alcA is closely linked to the positive control gene alcR. We have obtained cDNA clones of alcA and aldA and genomic clones comprising alcA and alcR. The location of these genes in a genomic clone carrying a 13-kb insert was determined by subcloning and subsequent transformation of previously characterised point mutants. We have characterised at the physical level some large deletions encompassing both linked genes. We have shown that induction affects the level of RNA hybridisible with alcA and aldA probes. Mutations in the regulatory gene alcR, result in non-inducibility of RNA hybridisible with either probe. Thus the induction process is possibly at the level of transcription. Analogous experiments suggest that carbon catabolite repression of alcohol dehydrogenase I is equally at the level of transcription.
在构巢曲霉中，乙醇脱氢酶（ADH）I和乙醛脱氢酶（AldDH）可被乙醛共同诱导（帕特曼等人，1983年；西利-刘易斯和洛金顿，1984年），并受到碳分解代谢物阻遏。结构基因alcA和aldA不连锁，但alcA与正调控基因alcR紧密连锁。我们已获得alcA和aldA的cDNA克隆以及包含alcA和alcR的基因组克隆。通过亚克隆以及对先前表征的点突变体进行后续转化，确定了这些基因在携带13 kb插入片段的基因组克隆中的位置。我们在物理层面表征了一些包含这两个连锁基因的大片段缺失。我们已表明，诱导作用会影响与alcA和aldA探针杂交的RNA水平。调控基因alcR中的突变导致与任一探针杂交的RNA无法被诱导。因此，诱导过程可能发生在转录水平。类似实验表明，乙醇脱氢酶I的碳分解代谢物阻遏同样发生在转录水平。
