ABSTRACT
Stagonosporopsis cucurbitacearum is an important plant-pathogenic fungus that causes stem and leaf blight diseases in a variety of crops. Here, we report the characterization of a novel victorivirus, tentatively named "Stagonosporopsis cucurbitacearum victorivirus 1" (ScVV-1), isolated from the S. cucurbitacearum isolate M-7. The ScVV-1 genome is 5,165 bp in length with a predicted GC content of 60.1% and contains two large open reading frames (ORF 1 and ORF2) encoding putative proteins that share significant sequence similarity with coat proteins (CPs) and RNA-dependent RNA polymerases (RdRps) of mycoviruses of the family Totiviridae. The ScVV-1 RdRp appears to be translated using a stop-initiation pentanucleotide UAAUG sequence. Phylogenetic analysis based on CP and RdRp amino acid (aa) sequences both indicated that ScVV-1 belongs to the genus Victorivirus in the family Totiviridae. To our knowledge, this is the first full-length genome sequence of a victorivirus infecting S. cucurbitacearum.
Subject(s)
Ascomycota , Fungal Viruses , Totiviridae , Nicotiana/genetics , Phylogeny , Totiviridae/genetics , Ascomycota/genetics , Fungal Viruses/genetics , Open Reading Frames , Genome, Viral , RNA, Viral/genetics , RNA, Viral/chemistry , RNA, Double-StrandedABSTRACT
The cigarette beetle, Lasioderma serricorne (Fabricius) (Coleoptera: Anobiidae), is a destructive stored product pest worldwide. Adult cigarette beetles are known to rely on host volatiles and pheromones to locate suitable habitats for oviposition and mating, respectively. However, little is known about the chemosensory mechanisms of these pests. Soluble chemoreception proteins are believed to initiate olfactory signal transduction in insects, which play important roles in host searching and mating behaviors. In this study, we sequenced the antennal transcriptome of L. serricorne and identified 14 odorant-binding proteins (OBPs), 5 chemosensory proteins (CSPs), and 2 Niemann-Pick C2 proteins (NPC2). Quantitative realtime PCR (qPCR) results revealed that several genes (LserOBP2, 3, 6, and 14) were predominantly expressed in females, which might be involved in specific functions in this gender. The five LserOBPs (LserOBP1, 4, 8, 10, and 12) that were highly expressed in the male antennae might encode proteins involved in specific functions in males. These findings will contribute to a better understanding of the olfactory system in this stored product pest and will assist in the development of efficient and environmentally friendly strategies for controlling L. serricorne.
Subject(s)
Coleoptera , Receptors, Odorant , Animals , Arthropod Antennae/metabolism , Coleoptera/genetics , Coleoptera/metabolism , Female , Gene Expression Profiling , Insect Proteins/genetics , Insect Proteins/metabolism , Male , Phylogeny , Receptors, Odorant/genetics , Receptors, Odorant/metabolism , TranscriptomeABSTRACT
BACKGROUND: Sheath blight, caused by Rhizoctonia solani, can be effectively controlled by application of the succinate dehydrogenase inhibitor thifluzamide. Although the risk of resistance to thifluzamide in R. solani had been reported, the thifluzamide-resistance mechanism and the evolution of thifluzamide-resistance in R. solani have not been investigated in detail. RESULTS: No differences were found between the sequences of proteins SDHA, SDHC, and SDHD in thifluzamide-sensitive isolates and thifluzamide-resistant mutants, but a single point mutation H249Y was found in SDHB. Two different types of thifluzamide-resistant R. solani mutants were characterized: homokaryotic, carrying only the resistance allele; and heterokaryotic, retaining the wild-type allele in addition to the resistance allele. The resistance level differed according to the nuclear composition at codon 249 in the sdhB gene. Molecular docking results suggested that the point mutation (H249Y) might significantly alter the affinity of thifluzamide and SDHB protein. Heterokaryotic mutants were able to evolve into a homokaryon when repeatedly cultured on agar media or rice plants in the presence of thifluzamide, but thifluzamide treatment had no effect on the genotypes of homokaryotic mutants or sensitive isolates. CONCLUSION: This study showed that H249Y in SDHB protein could cause thifluzamide resistance in R. solani. Fungicide application could promote heterokaryotic mutants to evolve into a homokaryon. © 2020 Society of Chemical Industry.
Subject(s)
Point Mutation , Rhizoctonia , Anilides , Molecular Docking Simulation , Plant Diseases , Rhizoctonia/genetics , ThiazolesABSTRACT
Talaromyces verruculosus has long been known to be a supreme cellulase and antimicrobial extrolite producer. Here we report the draft genome of T. verruculosus strain TS63-9, which has a very high pectinase activity. The assembled draft genome is 37.35 Mbp with 11,447 predicted protein-coding genes, among which 532 are annotated to be carbohydrate active enzymes (CAZymes) and 225 are polysaccharide-degrading enzymes.
Subject(s)
Genome, Fungal , Talaromyces/genetics , Fungal Proteins/genetics , Fungal Proteins/metabolism , Genome Size , Polysaccharides/metabolism , Talaromyces/classification , Talaromyces/enzymologyABSTRACT
The hrp genes exist in 4 kinds of Gram-negative plant pathogenic bacteria and are responsible for the pathogenicity of bacteria. They can induce hypersensitive response on non-host and resistant plants. In the present paper, we summarized the hrp genes clusters, the relationship between hrp and avr genes, harpin proteins encoded by hrp genes, modulation and function of hrp genes, and plant-bacteria interactions mediated by hrp genes in more details. Moreover, trends in future research of plant pathogenic bacteria hrp genes have also been analyzed.
