Requirement of LaeA for secondary metabolism and sclerotial production in Aspergillus flavus

Fungal Genet Biol. 2008 Oct;45(10):1422-9. doi: 10.1016/j.fgb.2008.06.009. Epub 2008 Jul 11.


The nuclear regulator LaeA has been shown to govern production of multiple secondary metabolites in Aspergillus nidulans and Aspergillus 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 DeltalaeA 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 DeltalaeA, 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.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Aflatoxins / biosynthesis
  • Arachis / microbiology
  • Aspergillus flavus / genetics
  • Aspergillus flavus / growth & development*
  • Aspergillus flavus / metabolism*
  • Fruiting Bodies, Fungal / genetics
  • Fruiting Bodies, Fungal / growth & development*
  • Fruiting Bodies, Fungal / metabolism*
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism*
  • Gene Expression Regulation, Fungal
  • Mutation
  • Plant Diseases / microbiology
  • Seeds / microbiology
  • Spores, Fungal / genetics
  • Spores, Fungal / growth & development
  • Spores, Fungal / metabolism


  • Aflatoxins
  • Fungal Proteins