Submitted to: National Fusarium Head Blight Forum Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 12/11/2005
Publication Date: 12/11/2005
Citation: Seong, K., Xu, J., Kistler, H.C. 2005. Gene expression analysis of conidium maturation and germination in Fusarium graminearum. In: Proceedings of the National Fusarium Head Blight Forum, December 11-13, 2005, Milwaukee, Wisconsin. p. 168.
Technical Abstract: To understand the infection cycle of the head blight pathogen F. graminearum, gene expression profiles were monitored in newly formed conidia, conidia that had been desiccated for 10 days and germinating conidia using the 18K feature F. graminearum Affymetrix GeneChip. A total of 6,384 positive signals were detected in newly formed spores with detection p value <0.001. Enhanced expression of many genes involved in transcription or transcriptional regulation and metabolism such as glycolysis, the glyoxylate cycle, and '-oxidation imply that newly formed conidia are not dormant cells but rather are metabolically active. Surprisingly, a total of 2,916 positive signals were detected even in mature conidia. Among 543 genes that were up-regulated more than 2-fold upon spore maturation were many genes involved in autophagy, proteolysis, protein secretion, and cell wall synthesis. After suspending conidia in liquid complete medium for 2h, a total of 5,587 signals were detected (p value <0.001) and 2,593 signals were up-regulated more than 2-fold in these swollen spores. Genes involved in transcription, RNA splicing, protein synthesis, and amino acid and nucleotide metabolism were highly induced during the initiation of spore germination. Up-regulation of proteasome components and secretory proteins was observed as germlings established polarized growth after 8h of incubation. Many stage-specific genes and events during spore maturation and germination were identified and will be discussed.