Identification of differentially expressed genes during aflatoxin biosynthesis in Aspergillus flavus

Greg R. OBrian and Gary A. Payne

Author address: 

Department of Plant Pathology, North Carolina State University, Raleigh NC 27695-7616


Aflatoxins are polyketide derived secondary metabolites whose biosynthesis can be induced by simple sugars. We are interested in identifying those genes differentially expressed during aflatoxin biosynthesis and profiling their expression during aflatoxin biosynthesis. Candidate genes for study were identified by hybridizing an array of 100,000 Aspergillus flavus cDNA clones with probes made from mRNA collected from cultures of the fungus in the log phase of aflatoxin production. A subset of clones expressed primarily during aflatoxin biosynthesis was chosen for sequence analysis. Quality EST sequences (100 base pairs or greater with at least phred 20) were obtained for over 2200 clones. Sequence analysis revealed the presence of over 600 unique clones. Many of the unique ESTs showed no homology to sequences in the public databases. Among ESTs with homology to sequences with known functions are those coding for signal transduction pathways, secondary metabolism, glucose regulation, cell wall biosynthesis, and cell cycle control. We have developed a microarray containing replicates of our unique clone set and are in the process of further analyzing these clones to establish a gene expression profile during aflatoxin biosynthesis.

abstract No: 


Full conference title: 

21st Fungal Genetics Conference
    • Fungal Genetics Conference 21st (2000)