Transcriptome analysis of Sporisorium scitamineum reveals critical environmental signals for fungal sexual mating and filamentous growth

Abstract

BackgroundSporisorium scitamineum causes the sugarcane smut disease, one of the most serious constraints to global sugarcane production. S. scitamineum possesses a sexual mating system composed of two mating-type loci, a and b locus. We previously identified and deleted the b locus in S. scitamineum, and found that the resultant SsΔMAT-1b mutant was defective in mating and pathogenicity.ResultsTo further understand the function of b-mating locus, we carried out transcriptome analysis by comparing the transcripts of the mutant strain SsΔMAT-1b, from which the SsbE1 and SsbW1 homeodomain transcription factors have previously been deleted, with those from the wild-type MAT-1 strain. Also the transcripts from SsΔMAT-1b X MAT-2 were compared with those from wild-type MAT-1 X MAT-2 mating. A total of 209 genes were up-regulated (p < 0.05) in the SsΔMAT-1b mutant, compared to the wild-type MAT-1 strain, while 148 genes down-regulated (p < 0.05). In the mixture, 120 genes were up-regulated (p < 0.05) in SsΔMAT-1b X MAT-2, which failed to mate, compared to the wild-type MAT-1 X MAT-2 mating, and 271 genes down-regulated (p < 0.05). By comparing the up- and down-regulated genes in these two sets, it was found that 15 up-regulated and 37 down-regulated genes were common in non-mating haploid and mating mixture, which indeed could be genes regulated by b-locus. Furthermore, GO and KEGG enrichment analysis suggested that carbon metabolism pathway and stress response mediated by Hog1 MAPK signaling pathway were altered in the non-mating sets.ConclusionsExperimental validation results indicate that the bE/bW heterodimeric transcriptional factor, encoded by the b-locus, could regulate S. scitamineum sexual mating and/or filamentous growth via modulating glucose metabolism and Hog1-mediating oxidative response.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-016-2691-5) contains supplementary material, which is available to authorized users.

cAMP/PKA signalling pathway regulates redox homeostasis essential for Sporisorium scitamineum mating/filamentation and virulence

“…Genomic DNA of S. scitamineum strains was extracted from the sporidial culture grown on YePSA medium for 2 days at 28 C, using an SDS-based (Góesneto et al, 2005). Total RNA extract from fresh haploid sporidia was performed with TRIzol reagent (Life Technologies, 15596-026) following established protocol (Yan et al, 2016). The S. scitamineum strains used for RNA extract were grown in minimal medium at 28 C to reach OD 600 = 1.0.…”

“…Construction of T-DNA insertion mutant library was conducted by agrobacterium tumefaciens-mediated transformation (ATMT) with plasmid pEX2 (carrying Hygromycin resistance cassette) (Yan et al, 2016). The transformants were selected with 200 μg mL −1 hygromycin (Merck, 31282-04-9).…”

“…This is consistent with redox signalling in animal cells, under physiological or pathological conditions (Schieber and Chandel, ). Our previous study also showed that, addition of antioxidant GSH suppressed S. scitamineum mating or filamentation in vitro (Yan et al ., ). It remains unknown as to how such redox signalling is regulated in S. scitamineum sexual mating, filamentation and/or pathogenicity.…”

Cuminal Inhibits Trichothecium roseum Growth by Triggering Cell Starvation: Transcriptome and Proteome Analysis

“…Gene ontology (GO) annotation was conducted with Blast2GO software. Kyoto Encyclopedia of Genes and Genomes (KEGG) annotation was performed with the database http://www.genome.jp/kegg/ pathway.html [32].…”

“…As described by Yan et al [32], differential transcript accumulation in samples of controls and treatments was observed using bowtie2 and eXpress. The gene expression levels were calculated with fragments per kilobase per million method.…”