MFS Transporters and GABA Metabolism Are Involved in the Self-Defense Against DON in Fusarium graminearum

Frontiers in Plant Science

卷:9

Mengchun Wu¹  Huiquan Liu²  Cong Jiang²  Jin-Rong Xu³  Daipeng Chen⁴  Qinhu Wang⁴  Jindong Zhu⁴ 

[1] Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, United States;

[2] F University, Yangling, China;

[3] Innovation Experimental College, Northwest A&

[4] State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest A&

关键词: Fusarium head blight;    Fusarium graminearum;    DON resistance;    MFS transporter;    gamma-aminobutyric acid;   

DOI  :  10.3389/fpls.2018.00438

来源: DOAJ

【 摘 要 】

Trichothecene mycotoxins, such as deoxynivalenol (DON) produced by the fungal pathogen, Fusarium graminearum, are not only important for plant infection but are also harmful to human and animal health. Trichothecene targets the ribosomal protein Rpl3 that is conserved in eukaryotes. Hence, a self-defense mechanism must exist in DON-producing fungi. It is reported that TRI (trichothecene biosynthesis) 101 and TRI12 are two genes responsible for self-defense against trichothecene toxins in Fusarium. In this study, however, we found that simultaneous disruption of TRI101 and TRI12 has no obvious influence on DON resistance upon exogenous DON treatment in F. graminearum, suggesting that other mechanisms may be involved in self-defense. By using RNA-seq, we identified 253 genes specifically induced in DON-treated cultures compared with samples from cultures treated or untreated with cycloheximide, a commonly used inhibitor of eukaryotic protein synthesis. We found that transporter genes are significantly enriched in this group of DON-induced genes. Of those genes, 15 encode major facilitator superfamily transporters likely involved in mycotoxin efflux. Significantly, we found that genes involved in the metabolism of gamma-aminobutyric acid (GABA), a known inducer of DON production in F. graminearum, are significantly enriched among the DON-induced genes. The GABA biosynthesis gene PROLINE UTILIZATION 2-2 (PUT2-2) is downregulated, while GABA degradation genes are upregulated at least twofold upon treatment with DON, resulting in decreased levels of GABA. Taken together, our results suggest that transporters influencing DON efflux are important for self-defense and that GABA mediates the balance of DON production and self-defense in F. graminearum.

【 授权许可】

Unknown