Plants use RNA silencing as a defense against viruses. In response, viruses encode various RNA silencing suppressors to counteract the antiviral silencing. Here, we identified p22 as a silencing suppressor of cucurbit chlorotic yellows crinivirus and showed that p22 interacts with CsSKP1LB1, a Cucumis sativus ortholog of S-phase kinase-associated protein 1 (SKP1). The F-box-like motif of p22 was identified through sequence analysis and found to be necessary for the interaction using a yeast two-hybrid assay. The involvement of the F-box-like motif in p22 silencing suppressor activity was determined. Proteomics analysis of Nicotiana benthamiana leaves expressing p22, and its F-box-like motif deletion mutant showed 228 differentially expressed proteins and five enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways: ABC transporters, sesquiterpenoid and triterpenoid biosynthesis, ubiquitin-mediated proteolysis, riboflavin metabolism, and cysteine and methionine metabolism. Collectively, our results demonstrate the interaction between p22 and CsSKP1LB1 and show that the deletion of F-box-like motif inhibits p22 silencing suppressor activity. The possible pathways regulated by the p22 through the F-box-like motif were identified using proteomics analysis.
The trihelix transcription factor, which is a plant-specific family, play a critical role in plant growth and development and stress responses. Drought is the main limiting factor affecting yield of maize (Zea mays). However, the identification and characterization of this gene family in maize and its biological functions in response to drought stress have not been reported. Here, 46 Zea mays trihelix genes (ZmTHXs) were identified in the genome. Phylogenetic analysis of the ZmTHXs revealed that the genes were clustered into five subfamilies: GT-1, GT-2, GTγ, SH4, and SIP1. Chromosomal localization analysis showed that the 46 ZmTHXs were unevenly distributed across 10 chromosomes in maize. Cis-acting elements related to abiotic stress in ZmTHXs were found. Most ZmTHXs genes showed significant changes in expression levels under drought treatment. In addition, ZmTHX15-overexpressing Arabidopsis exhibited stronger drought tolerance with less secondary oxidative damage and higher photosynthetic rate. These findings could serve as a basis for future studies on the roles of ZmTHXs and the potential genetic markers for breeding stress-resistant and high-yielding maize varieties.
Sesame (Sesamum indicum) is grown as an important oilseed crop worldwide. Viral diseases on sesame cause economic losses. In China the main regions for seasame production is distributed in Henan and Hubei provinces. Surveys of viral diseases on sesame were conducted in the summer of 2015 in Zhengzhou, Henan Province, China, and the approximate percent of virus diseased plants during our survey was 10%.. Mosaic, leaf deformation, and yellowing symptoms were observed in diseased sesame plants. To identify the causal viral pathogens, leaves were sampled from 6 symptomatic plants for total RNA extraction using Trizol reagent and equal amount of RNA from these plants were pooled for small-RNA (sRNA) deep sequencing (Illumnia Hiseq2500). In total 26187139 reads were obtained, and among them clear reads of 21- to 24-nucleotide(nt) were assembled and used to search homologous sequences in GenBank by BLAST. BLAST searches identified three potyviruses, Watermelon mosaic virus (WMV), Bean common mosaic virus (BCMV) ...
Sucrose non-fermenting protein 7 (SNF7) is a core operator of the endosomal sorting complex required for transport III (ESCRT-III) component mediating protein sorting and degradation. To date, the SNF7 gene family remains poorly characterized in plants, particularly in maize (Zea mays L.). Here, we integrated bioinformatic and transcriptomic analyses to systematically characterize the ZmSNF7 gene family and its regulatory potential in stress responses. In total, 20 ZmSNF7 genes were identified genome-wide and classified into three phylogenetic clades, with conserved motifs and similar tertiary structures within the same clade. Abundant hormone- and stress-responsive cis-elements were detected in their promoters. Protein interaction prediction indicated ZmSNF7 proteins interact with intra-family members and other ESCRT components. Gene Ontology (GO) enrichment analysis suggested ZmSNF7s are primarily involved in endomembrane system organization and vesicular trafficking. Transcriptomic data revealed divergent ZmSNF7 expression patterns under drought, Rice black-streaked dwarf virus (RBSDV) infection, Colletotrichum graminicola (C. graminicola) inoculation and Asian corn borer (ACB) infestation. Collectively, this study comprehensively characterized the ZmSNF7 gene family and broadened our functional understanding of ZmSNF7 in mediating plant responses to biotic and abiotic stresses.
Oral secretions (OS) of the Asian corn borer (Ostrinia furnacalis) play pivotal roles in its interactions with host plants. To systematically characterize the composition and potential functions of OS, 245 functionally annotated proteins from O. furnacalis reared on artificial diet were identified using an integrated approach combining transcriptomics and liquid chromatography–tandem mass spectrometry (LC-MS/MS). Bioinformatics analyses were further performed to predict 16 effector proteins. Subsequent tissue-specific expression assays were conducted to quantify the transcriptional levels of genes encoding these effector proteins in salivary glands, guts, and residual tissues. Among these genes, OfGDH2, OfPero2, OfPero3, and OfCBP were highly expressed in salivary glands, OfGDH3, OfRGD, OfEST1, OfEST2, OfMET, and Offerrin showed high expression in guts, while OfSP34 was abundantly expressed in both salivary glands and guts. This study represents the first systematic characterization of the molecular profile of O. furnacalis OS, thereby laying a solid foundation for future investigations into the molecular mechanisms underlying the host adaptation of this pest.