Requirement of LaeA for Secondary Metabolism and Sclerotial Production in Aspergillus flavus
United States Agency for International Development, National Institutes of Health, National Science Foundation
LAG-G-00-96-90013-00, 5SO6GM08008, MCB-0236393, 2002-35201-12562,R01 AI065728-01A1
Department of Biology
The nuclear regulator LaeA has been shown to govern production of multiple secondary metabolites in A. nidulans and A. fumigatus. Herein we examine the role of this protein in Aspergillus flavus. Similarly as in other Aspergilli, LaeA had a major effect on A. flavus secondary metabolism where ΔlaeA and over-expression laeA (OE::laeA) strains yielded opposite phenotypes resulting in decreased (increased) secondary metabolite production. The two mutant strains also exhibited striking morphological phenotypes in the loss (increase) of sclerotial production in comparison to wildtype. Growth on seed was marked by decreased (increased) conidial and aflatoxin production of the respective mutants; this was accompanied by decreased lipase activity in ΔlaeA, an enzymatic process correlated with seed maceration. Transcriptional examination of the mutants showed LaeA negatively regulates expression of its recently identified nuclear partner VeA, another global regulator of A. flavus secondary metabolites and sclerotia.
Ireland, Shubha Kale; Milde, L.; Trapp, M. K.; Frisvad, J. C.; Keller, N. P.; and Bok, J. W., "Requirement of LaeA for Secondary Metabolism and Sclerotial Production in Aspergillus flavus" (2008). Faculty and Staff Publications. 182.