Posttranslational hypusination of the eukaryotic translation initiation factor-5A regulates Fusarium graminearum virulence

• Published in: Scientific reports 2016-04, Vol.6 (1), p.24698, Article 24698
• Main Authors: Martinez-Rocha, Ana Lilia, Woriedh, Mayada, Chemnitz, Jan, Willingmann, Peter, Kröger, Cathrin, Hadeler, Birgit, Hauber, Joachim, Schäfer, Wilhelm
• Format: Article
• Language: English
• Subjects: 14/63; 38/22; 38/35; 38/44; 38/71; 38/77; 631/326/193/2538; 631/326/193/2542; 82/1; 82/29; Amino acids; Cereals; Conidia; Crop production; Deoxynivalenol; Enzymes; Eukaryotic Translation Initiation Factor 5A; Fusarium - pathogenicity; Fusarium - physiology; Gene Expression; Genes, Fungal; Humanities and Social Sciences; Hydroxylase; Initiation factor eIF-5A; Life cycles; Lysine - analogs & derivatives; Lysine - biosynthesis; Microbial Viability - genetics; multidisciplinary; Mutation; Mycotoxins; Mycotoxins - biosynthesis; Pathogenicity; Pathogens; Peptide Initiation Factors - genetics; Peptide Initiation Factors - metabolism; Plant Diseases; Protein Processing, Post-Translational; Reactive Oxygen Species - metabolism; RNA-Binding Proteins - genetics; RNA-Binding Proteins - metabolism; Science; Science (multidisciplinary); Sexual reproduction; Stress, Physiological - genetics; Triticum - metabolism; Triticum - microbiology; Virulence; Wheat
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep24698

Activation of eukaryotic translation initiation factor eIF5A requires a posttranslational modification, forming the unique amino acid hypusine. This activation is mediated by two enzymes, deoxyhypusine synthase, DHS, and deoxyhypusine hydroxylase, DOHH. The impact of this enzymatic complex on the life cycle of a fungal pathogen is unknown. Plant pathogenic ascomycetes possess a single copy of the eIF5A activated by hypusination. We evaluated the importance of imbalances in eIF5A hypusination in Fusarium graminearum , a devastating fungal pathogen of cereals. Overexpression of DHS leads to increased virulence in wheat, elevated production of the mycotoxin deoxynivalenol, more infection structures, faster wheat tissue invasion in plants and increases vegetatively produced conidia. In contrast, overexpression of DOHH completely prevents infection structure formation, pathogenicity in wheat and maize, leads to overproduction of ROS, reduced DON production and increased sexual reproduction. Simultaneous overexpression of both genes restores wild type-like phenotypes. Analysis of eIF5A posttranslational modification displayed strongly increased hypusinated eIF5A in DOHH overexpression mutant in comparison to wild type, and the DHS overexpression mutants. These are the first results pointing to different functions of differently modified eIF5A.