Transcriptome analysis of maize resistance to Fusarium graminearum

BMC Genomics

Research Article

Yanling Guo¹  Dongfeng Zhang¹  Qin Yang¹  Chao Wang¹  Yongjie Liu¹  Chuanyu Ma¹ 

[1] National Maize Improvement Center of China, China Agriculture University, 2 West Yuanmingyuan Rd., Haidian District, 100193, Beijing, China;

关键词: Zea mays;    RNAseq;    Gibberella;    Constitutive resistance;    Tryptophan;    Auxin signaling pathway;    Polar auxin transport;   

DOI  :  10.1186/s12864-016-2780-5

 received in 2016-01-21, accepted in 2016-05-26,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundGibberella stalk rot caused by Fusarium graminearum is one of the most destructive soil-borne diseases of maize (Zea mays L.). Chemical means of controlling Gibberella stalk rot are not very effective; development of highly resistant hybrids is the best choice for disease control. Hence, understanding of the molecular basis underlying maize resistance against Gibberella stalk rot would undoubtedly facilitate the resistance breeding for stalk rot.ResultsTwo quantitative trait loci (QTL), qRfg1 and qRfg2, conferring resistance to Gibberella stalk rot were detected in our previous study. Three near-isogenic lines (NILs) of maize with either qRfg1 (NIL1) or qRfg2 (NIL2), or neither (NIL3) were generated and subjected to RNA sequencing to study the transcriptional changes after F. graminearum inoculation at 0 (control), 6, and 18 h post-inoculation (hpi). In total, 536,184,652 clean reads were generated, and gene expression levels were calculated using FPKM (fragments per kilobase of exon model per million mapped reads). A total of 7252 differentially expressed genes (DEGs) were found in the three NILs after F. graminearum inoculation. As many as 2499 DEGs were detected between NIL1 and NIL3 at 0 hpi, of which 884 DEGs were more abundant in NIL1 and enriched in defense responses. After F. graminearum inoculation, 1070 and 751 genes were exclusively up- and downregulated, respectively, in NIL1 as compared to NIL3. The 1070 upregulated DEGs were enriched in growth/development, photosynthesis/biogenesis, and defense-related responses. Genes encoding putative auxin-induced proteins and GH3 family proteins in auxin signaling pathway were highly induced and lasted longer in NIL3. Genes involved in polar auxin transport (PAT) were more abundant in NIL3 as compared with NIL2.ConclusionsThe qRfg1 confers its resistance to Gibberella stalk rot through both constitutive and induced high expression of defense-related genes; while qRfg2 enhances maize resistance to the disease via relatively lower induction of auxin signaling and repression of PAT. The defense-related transcriptional changes underlying each QTL will undoubtedly facilitate our understanding of the resistance mechanism and resistance breeding for maize stalk rot.

【 授权许可】

CC BY   
© The Author(s). 2016