Large-scale transcriptome comparison of sunflower genes responsive to Verticillium dahliae

Abstract

BackgroundSunflower Verticillium wilt (SVW) is a vascular disease caused by root infection with Verticillium dahliae (V. dahlia). It is a serious threat to the yield and quality of sunflower. However, chemical and agronomic measures for controlling this disease are not effective. The selection of more resistant genotypes is a desirable strategy to reduce contamination. A deeper knowledge of the molecular mechanisms and genetic basis underlying sunflower Verticillium wilt is necessary to accelerate breeding progress.ResultsAn RNA-Seq approach was used to perform global transcriptome profiling on the roots of resistant (S18) and susceptible (P77) sunflower genotypes infected with V. dahlia. Different pairwise transcriptome comparisons were examined over a time course (6, 12 and 24 h, and 2, 3, 5 and 10 d post inoculation). In RD, SD and D datasets, 1231 genes were associated with SVW resistance in a genotype-common transcriptional pattern. Moreover, 759 and 511 genes were directly related to SVW resistance in the resistant and susceptible genotypes, respectively, in a genotype-specific transcriptional pattern. Most of the genes were demonstrated to participate in plant defense responses; these genes included peroxidase (POD), glutathione peroxidase, aquaporin PIP, chitinase, L-ascorbate oxidase, and LRR receptors. For the up-regulated genotype-specific differentially expressed genes (DEGs) in the resistant genotype, higher average fold-changes were observed in the resistant genotype compared to those in the susceptible genotype. An inverse effect was observed in the down-regulated genotype-specific DEGs in the resistant genotype. KEGG analyses showed that 98, 112 and 52 genes were classified into plant hormone signal transduction, plant-pathogen interaction and flavonoid biosynthesis categories, respectively. Many of these genes, such as CNGC, RBOH, FLS2, JAZ, MYC2 NPR1 and TGA, regulate crucial points in defense-related pathway and may contribute to V. dahliae resistance in sunflower.ConclusionsThe transcriptome profiling results provided a clearer understanding of the transcripts associated with the crosstalk between sunflower and V. dahliae. The results identified several differentially expressed unigenes involved in the hyper sensitive response (HR) and the salicylic acid (SA)/jasmonic acid (JA)-mediated signal transduction pathway for resistance against V. dahliae. These results are useful for screening resistant sunflower genotypes.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-016-3386-7) contains supplementary material, which is available to authorized users.

Transcriptome analysis reveals the defense mechanism of cotton against Verticillium dahliae in the presence of the biocontrol fungus Chaetomium globosum CEF-082

“…The pathways of plant-pathogen interaction and flavonoid biosynthesis were also induced in sunflower plants infected with V. dahliae [16], and the results were also consistent with those of Tan [27], who reported that most DEGs in tomato were associated with phenylpropanoid metabolism and plantpathogen interaction pathways. However, the glutathione metabolism pathway has rarely been reported in the transcriptome of cotton plants treated with V. dahliae.…”

“…In addition, DEGs related to JA, ET, SA, BR and cytokinin were induced in cotton plants treated only with CEF-082. The 8 plant hormones were also induced after infection with V. dahliae in sunflower [16]. The responses of the A. thaliana auxin receptors TIR1, AFB1 and AFB3 and auxin transporter AXR4 were impaired upon infection with V. dahliae [30].…”

“…In recent years, transcriptomic studies of the defense responses of plants infected with V. dahliae have become increasingly common, and several signal transduction pathways and key genes have been identified, including those involved in plant hormone signal transduction, plant-pathogen interaction, and phenylpropanoid-related and ubiquitin-mediated signals in cotton; additionally, these studies have investigated members of key regulatory gene families, such as receptor-like protein kinases (RLKs), WRKY transcription factors and cytochrome P450s (CYPs) [3]. The expression levels of phenylalanine ammonia-lyase (PAL), 4-coumarate-CoA ligase (4CL), cinnamyl alcohol dehydrogenase (CAD), caffeoyl-CoA O-methyltransferase (CCoAOMT), and caffeoyl O-methyltransgerase (COMT) in the phenylalanine metabolism pathway have been shown to be upregulated in sea-island cotton [2]; the expression levels of 401 transcription factors(TFs), mainly in the MYB, bHLH, AP2-EREBP, NAC, and WRKY families, have been shown to be up-or downregulated in response to V. dahliae in Arabidopsis thaliana [15]; and genes encoding cyclic nucleotide gated channel (CNGC), respiratory burst oxidase homologue (RBOH), flagellin-sensitive 2 (FLS2), jasmonate ZIM domain-containing protein (JAZ), transcription factor MYC2, regulatory protein NPR1 and transcription factor TGA have been shown to be induced by V. dahliae in sunflower [16]. Several studies have investigated transcript levels in plants in response to biocontrol agents [17,18].…”

Genome-wide characterization deciphers distinct properties of major intrinsic proteins in six Phytophthora species

“…MIPs have a main role in water and solute transport and aid in homeostasis during plant stress responses (Afzal et al, 2016). Recently, transcriptome data provided important clues about the involvement of MIPs in host-pathogen interactions (Galindo-Gonzàlez and Deyholos, 2016; Reeksting et al, 2016; Guo et al, 2017). Although there has been no study on PMIPs, in the present study, we identified and characterized a total of 126 MIP homologues from the genomes of six Phytophthora species, which cause severe economic losses because of devastating effects on numerous agriculturally and ornamentally important plants (Tyler et al, 2006; Haas et al, 2009; Lamour et al, 2012; Thines, 2014; Fawke et al, 2015; Derevnina et al, 2016; Wang et al, 2016).…”

Transcriptome analysis reveals the defense mechanism of cotton against Verticillium dahliae in the presence of the biocontrol fungus Chaetomium globosum CEF-082

“…In recent years, transcriptomic studies of the defense responses of plants infected with V. dahliae have become increasingly common, and several signal transduction pathways and key genes have been identified, including those involved in plant hormone signal transduction, plantpathogen interaction, and phenylpropanoid-related and ubiquitin-mediated signals in cotton; additionally, these studies have investigated members of key regulatory gene families, such as receptor-like protein kinases (RLKs), WRKY transcription factors and cytochrome P450s (CYPs) [3]. The expression levels of phenylalanine ammonia-lyase (PAL), 4-coumarate-CoA ligase (4CL), cinnamyl alcohol dehydrogenase (CAD), caffeoyl-CoA O-methyltransferase (CCoAOMT), and caffeoyl O-methyltransgerase (COMT) in the phenylalanine metabolism pathway have been shown to be upregulated in sea-island cotton [2]; the expression levels of 401 transcription factors (TFs), mainly in the MYB, bHLH, AP2-EREBP, NAC, and WRKY families, have been shown to be up-or downregulated in response to V. dahliae in Arabidopsis thaliana [15]; and genes encoding cyclic nucleotide gated channel (CNGC), respiratory burst oxidase homologue (RBOH), flagellin-sensitive 2 (FLS2), jasmonate ZIM domain-containing protein (JAZ), transcription factor MYC2, regulatory protein NPR1 and transcription factor TGA have been shown to be induced by V. dahliae in sunflower [16]. Several studies have investigated transcript levels in plants in response to biocontrol agents [17,18].…”