Comparative Transcriptome Profiles of Near-Isogenic Hexaploid Wheat Lines Differing for Effective Alleles at the 2DL FHB Resistance QTL

Abstract

Fusarium head blight (FHB), caused by the fungus Fusarium graminearum, represents one of the major wheat diseases worldwide, determining severe yield losses and reduction of grain quality due to the accumulation of mycotoxins. The molecular response associated with the wheat 2DL FHB resistance QTL was mined through a comprehensive transcriptomic analysis of the early response to F. graminearum infection, at 3 days post-inoculation, in spikelets and rachis. The analyses were conducted on two near isogenic lines (NILs) differing for the presence of the 2DL QTL (2-2618, resistant 2DL+ and 2-2890, susceptible null). The general response to fungal infection in terms of mRNAs accumulation trend was similar in both NILs, even though involving an higher number of DEGs in the susceptible NIL, and included down-regulation of the primary and energy metabolism, up-regulation of enzymes implicated in lignin and phenylpropanoid biosynthesis, activation of hormons biosynthesis and signal transduction pathways and genes involved in redox homeostasis and transcriptional regulation. The search for candidate genes with expression profiles associated with the 2DL QTL for FHB resistance led to the discovery of processes differentially modulated in the R and S NILs related to cell wall metabolism, sugar and JA signaling, signal reception and transduction, regulation of the redox status and transcription factors. Wheat FHB response-related miRNAs differentially regulated were also identified as putatively implicated in the superoxide dismutase activities and affecting genes regulating responses to biotic/abiotic stresses and auxin signaling. Altered gene expression was also observed for fungal non-codingRNAs. The putative targets of two of these were represented by the wheat gene WIR1A, involved in resistance response, and a gene encoding a jacalin-related lectin protein, which participate in biotic and abiotic stress response, supporting the presence of a cross-talk between the plant and the fungus.

A Comparative Transcriptome Analysis, Conserved Regulatory Elements and Associated Transcription Factors Related to Accumulation of Fusariotoxins in Grain of Rye (Secale cereale L.) Hybrids

“…Generally, in the transcriptomic study, we identified higher numbers of DEGs after inoculation in both hybrids. These results are in agreement with previous studies involving wheat, where plants were challenged with Fusarium species [ 45 , 50 , 51 ]. The KEGG analysis on DEGs revealed that DEGs associated with glycolysis and the mTOR signaling pathway were higher in the hybrid having less fusariotoxins (DH372), whereas carbon fixation in photosynthesis organisms, and pentose and glucuronate interconversions were most represented in the hybrid having higher levels of fusariotoxins (Helltop).…”

“…The differences found in drug metabolism via cytochrome P450 and other drug metabolism enzymes, mTOR signaling pathway, pentose and glucuronate interconversions could be the reason for differences observed in mycotoxin analysis of both hybrids. Similar KEGG pathways were identified in wheat [ 45 , 52 , 53 ], barley [ 54 ], and maize [ 55 ] after Fusarium infection. The glycolysis pathways have been known to play significant roles in plant pathogen interaction [ 56 ].…”

“…The fusariotoxins analysis in this study revealed that two rye hybrids have different detoxification abilities as one (Helltop) accumulated a higher level of fusariotoxins than the other (DH372) ( Table 1 ). Furthermore, transcriptome data generated in this study complements the resources recently made available for other cereals regarding FHB resistance [ 43 , 45 ]. Wheat and barley differ noticeably in this type of resistance; however, there is not much known in the case of rye.…”

QTL Mapping and Transcriptome Analysis to Identify Differentially Expressed Genes Induced by Septoria Tritici Blotch Disease of Wheat

“…Host plant resistance is considered as the most sustainable approach for decreasing yield losses caused by different pathogens in many crops, including wheat. Integrating analysis of linkage mapping and putative genes responsible for resistance can facilitate the improvement of wheat through the identification and utilization of molecular markers for effective marker-assisted selection [27]. This type of integrated analysis assisted in decreasing the number of candidate genes in different plant species, such as maize [28], Arabidopsis [29] and wheat [30].…”

A Comparison of sun, ovate, fs8.1 and Auxin Application on Tomato Fruit Shape and Gene Expression

“…The stages include inflorescence formation and flower initiation [1 Days Post flower Initiation (DPI)], initiation of outermost perianth organs (2-3 DPI), initiation of inner perianth organs (4 DPI), stamen initiation (5 DPI), carpel initiation (6-7 DPI), microsporangia initiation (8 DPI), ovule initiation (9 DPI), male meiosis (10 DPI), female meiosis (11-13 DPI) and anthesis (19 DPI) (Xiao et al 2009). In addition, near-isogenic lines (NILs) are powerful tools in both genetic and molecular studies (Chakrabarti et al 2013, Mu et al 2017, Biselli et al 2018. We have introgressed the sun, ovate and fs8.1 alleles into the LA1589 background to compare and contrast the effect of one or a combination of loci on morphological and physiological responses (Wu et al 2015).…”