کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
2181379 | 1095292 | 2008 | 10 صفحه PDF | دانلود رایگان |

The Aspergillus nidulans xlnR gene encodes a Zn2Cys6 transcription activator necessary for the synthesis of the main xylanolytic enzymes, i.e. endo-xylanases X22, X24 and X34, and β-xilosidase XlnD. Expression of xlnR is not sufficient for induction of genes encoding the xylanolytic complex, the presence of xylose is absolutely required. It has been established previously that the wide-domain carbon catabolite repressor CreA indirectly represses xlnA (encodes X22) and xlnB (encodes X24) genes as well as exerting direct repression on xlnA. This work provides evidence that CreA-mediated indirect repression occurs through repression of xlnR: (i) the xlnR gene promoter is repressed by glucose and this repression is abolished in creAd30 mutant strains and (ii) deregulated expression of xlnR completely relieves glucose repression of xlnA and xlnB. Thus, CreA and XlnR form a transcriptional cascade regulating A. nidulans xylanolytic genes.
Journal: Fungal Genetics and Biology - Volume 45, Issue 6, June 2008, Pages 984–993