Chang PK, et al. (2011) Loss of msnA, a Putative Stress Regulatory Gene, in Aspergillus parasiticus and Aspergillus flavus Increased Production of Conidia, Aflatoxins and Kojic Acid. Toxins (Basel) 3(1):82-104
Abstract: Production of the harmful carcinogenic aflatoxins by Aspergillus parasiticus and Aspergillus flavus has been postulated to be a mechanism to relieve oxidative stress. The msnA gene of A. parasiticus and A. flavus is the ortholog of Saccharomyces cerevisiae MSN2 that is associated with multi-stress response. Compared to wild type strains, the msnA deletion (msnA) strains of A. parasiticus and A. flavus exhibited retarded colony growth with increased conidiation. The msnA strains also produced slightly higher amounts of aflatoxins and elevated amounts of kojic acid on mixed cereal medium. Microarray assays showed that expression of genes encoding oxidative stress defense enzymes, i.e., superoxide dismutase, catalase, and cytochrome c peroxidase in A. parasiticus msnA, and the catalase A gene in A. flavus msnA, was up-regulated. Both A. parasiticus and A. flavus msnA strains produced higher levels of reactive oxygen species (ROS), and ROS production of A. flavus msnA addback strains was decreased to levels comparable to that of the wild type A. flavus. The msnA gene appears to be required for the maintenance of the normal oxidative state. The impairment of msnA resulted in the aforementioned changes, which might be used to combat the increased oxidative stress in the cells.
|Status: Published||Type: Journal Article||PubMed ID: 22069691|
Topics addressed in this paper
- To go to the Locus page for a gene, click on the gene name.
|Fungal Related Genes/Proteins|