Cpc1 mediates cross-pathway control independently of Mbf1 in Fusarium fujikuroi.
The deletion of glnA, encoding the glutamine synthetase (GS), had led to the down-regulation of genes involved in secondary metabolism and up-regulation of cpc1, the cross-pathway control transcription factor. In the present study, a Deltacpc1 mutant was created and used for transcriptional profiling by macroarray analysis. Most of the Cpc1 target genes were amino acid biosynthesis genes besides a homologue of the multi-protein bridging factor MBF1 that binds to the yeast Cpc1 homologue GCN4. We show that Deltambf1 mutants exhibit no Cpc1-related phenotype and that both proteins do not interact with each other in Fusarium fujikuroi. Moreover, results presented here suggest that Cpc1 is not responsible for the GS-dependent down-regulation of secondary metabolism and that its role is focused on the activation of amino acid biosynthesis in response to the amino acid status of the cell. Surprisingly, cross-pathway control is repressed by nitrogen limitation in an AreA-dependent manner.
Schönig
Birgit
B
Institut für Botanik der Westfälischen Wilhelms-Universität Münster, Schlossgarten 3, 48149 Münster, Germany.
Vogel
Sabine
S
Tudzynski
Bettina
B
D000596:Amino Acids / Q000235:genetics / Q000378:metabolism; D050976:Basic-Leucine Zipper Transcription Factors / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D015536:Down-Regulation; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D005670:Fusarium / Q000235:genetics* / Q000378:metabolism*; D020869:Gene Expression Profiling; D015966:Gene Expression Regulation, Fungal; D005816:Genetic Complementation Test; D005875:Gibberellins / Q000096:biosynthesis; D005974:Glutamate-Ammonia Ligase / Q000235:genetics / Q000378:metabolism; D053858:Metabolic Networks and Pathways; D008969:Molecular Sequence Data; D009584:Nitrogen / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D010641:Phenotype; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D020798:Two-Hybrid System Techniques; D015854:Up-Regulation
D000596:Amino Acids; D050976:Basic-Leucine Zipper Transcription Factors; D005656:Fungal Proteins; D005875:Gibberellins; D014157:Transcription Factors; C007842:gibberellic acid; D005974:Glutamate-Ammonia Ligase; D009584:Nitrogen