ABSTRACT
Potato virus H (PVH), belonging to the genus Carlavirus in the family Betaflexiviridae, was initially discovered in potato plants in Inner Mongolia, China (Li et al., 2013). Subsequently, it was documented to infect pepino, a perennial shrub of the Solanaceae family like potatoes (Abouelnasr et al., 2014). Tomato (Solanum lycopersicum L.), a major global crop, faces threats from various plant viruses. In an open field survey in Yunnan, China during July 2023, tomatoes (cultivar: Liangsi) showed typical virus symptoms: leaf yellowing, curling, mottling, and fruit with abnormal shape and color. Eleven symptomatic tomato samples were collected for high-throughput sequencing to identify the potential pathogen. RNA sequencing libraries were prepared using the TruSeq RNA sample prep kit (Illumina, San Diego, CA, USA), followed by RNA-seq sequencing on an Illumina HiSeq4000 platform (LC Sciences, USA). Approximately 77,928,560 paired-end reads (150-bp each) were generated. After quality control, 75,808,296 reads were retained and subjected to de novo assembly using Trinity (version 2.8.5). The assembled contigs, ranging from 198 nt to 15865 nt, were used as queries to search against the NCBI non-redundant protein sequence database (NR) or nucleotide sequence database (NT) to detect the potential pathogens using BLASTx and BLASTn program with a cutoff e-value of 10-5. As a consequence, certain contigs were assigned to 3 plant viruses, including PVH (the highest RdRp blastx identity to UAD82396.1: 97.8%), Capsicum chlorosis virus (CaCV, the highest RdRp blastx identity to APQ31267.1: 98.4%), and southern tomato virus (STV, the highest CP-RdRp fusion protein blastx identity to QOW17541.1: 99.74%). The presence of the identified 3 viruses was subsequently screened in the 11 tomato samples originally collected from the corresponding field. Notably, the specific detection primers for the PVH genome was designed from the newly assembled PVH genome (Forward primer: 5'- ATAGTTGTGCACTGTGTGCCTG-3'; Reverse primer: 5'-GCTTAAGGTTCTTAGCGTATTC-3'), targeting ~1.1kb. Consequently, PVH was detected in 3 out of 11 samples: 2 leaf samples and 1 fruit sample, with one leaf sample showing a single infection. The complete genome sequence of PVH in tomatoes (PVH-tomato) was successfully obtained by assembling nine overlapping regions spanning the entire PVH-tomato genome, following the RT-PCR and the 5' RACE and 3' RACE approaches, and deposited in NCBI nucleotide database with accession number OR397130.1Phylogenetic analysis based on the full genome sequences of PVH-tomato and other publicly available PVH isolates revealed that PVH-tomato was closely related to a PVH isolate found in potatoes in Yunnan (blastn similarity: 97.76%) (Fig. S1A). To test PVH-tomato infectivity and pathogenicity, four healthy Nicotiana benthamiana and four healthy tomato plants were mechanically inoculated with PVH-infected leaf sap; controls used sap from healthy plants. Three weeks post-inoculation, all N. benthamiana (4/4) and three tomato plants (3/4) were PVH-positive by RT-PCR. Symptoms were milder in N. benthamiana, and only two tomato plants (2/4) showed leaf curling. No PVH was detected in control samples (Figure S1B, S1C). Sanger sequencing confirmed the amplicons' expected length of 1093 bp. Previously, PVH was documented only in potato and pepino. This is the first report of tomatoes as natural PVH hosts and PVH infecting N. benthamiana under lab conditions.
ABSTRACT
The virus family Phenuiviridae (order Hareavirales, comprising segmented negative-sense single stranded RNA viruses) has highly diverse members that are known to infect animals, plants, protozoans, and fungi. In this study, we identified a novel phenuivirus infecting a strain of the entomopathogenic fungus Cordyceps javanica isolated from a small brown plant hopper (Laodelphax striatellus), and this virus was tentatively named "Cordyceps javanica negative-strand RNA virus 1" (CjNRSV1). The CjNRSV1 genome consists of three negative-sense single stranded RNA segments (RNA1-3) with lengths of 7252, 2401, and 1117 nt, respectively. The 3'- and 5'-terminal regions of the RNA1, 2, and 3 segments have identical sequences, and the termini of the RNA segments are complementary to each other, reflecting a common characteristic of viruses in the order Hareavirales. RNA1 encodes a large protein (â¼274 kDa) containing a conserved domain for the bunyavirus RNA-dependent RNA polymerase (RdRP) superfamily, with 57-80% identity to the RdRP encoded by phenuiviruses in the genus Laulavirus. RNA2 encodes a protein (â¼79 kDa) showing sequence similarity (47-63% identity) to the movement protein (MP, a plant viral cell-to-cell movement protein)-like protein (MP-L) encoded by RNA2 of laulaviruses. RNA3 encodes a protein (â¼28 kDa) with a conserved domain of the phenuivirid nucleocapsid protein superfamily. Phylogenetic analysis using the RdRPs of various phenuiviruses and other unclassified phenuiviruses showed CjNRSV1 to be grouped with established members of the genus Laulavirus. Our results suggest that CjNRSV1 is a novel fungus-infecting member of the genus Laulavirus in the family Phenuiviridae.
Subject(s)
Cordyceps , Genome, Viral , Phylogeny , RNA, Viral , Cordyceps/genetics , RNA, Viral/genetics , Fungal Viruses/classification , Fungal Viruses/genetics , Fungal Viruses/isolation & purification , Viral Proteins/genetics , Negative-Sense RNA Viruses/genetics , Negative-Sense RNA Viruses/classification , RNA-Dependent RNA Polymerase/genetics , RNA Viruses/genetics , RNA Viruses/classification , RNA Viruses/isolation & purification , Amino Acid Sequence , Open Reading FramesABSTRACT
A novel monopartite dsRNA virus, tentatively named "sponge gourd amalgavirus 1" (SGAV1), was discovered by high-throughput sequencing in sponge gourd (Luffa cylindrica) displaying mosaic symptoms in Jiashan County, Zhejiang Province, China. The genome of SGAV1 is 3,447 nucleotides in length and contains partially overlapping open reading frames (ORFs) encoding a putative replication factory matrix-like protein and a fusion protein, respectively. The fusion protein of SGAV1 shares 57.07% identity with the homologous protein of salvia miltiorrhiza amalgavirus 1 (accession no. DAZ91057.1). Phylogenetic analysis based on the RNA-dependent RNA polymerase (RdRp) protein suggests that SGAV1 belongs to the genus Amalgavirus of the family Amalgaviridae. Moreover, analysis of SGAV1-derived small interfering RNAs indicated that SGAV1 was actively replicating in the host plant. Semi-quantitative RT-PCR showed higher levels of SGAV1 expression in leaves than in flowers and fruits. This is the first report of a novel amalgavirus found in sponge gourd in China.
Subject(s)
Genome, Viral , Luffa , Open Reading Frames , Phylogeny , Genome, Viral/genetics , Luffa/virology , Animals , China , Double Stranded RNA Viruses/genetics , Double Stranded RNA Viruses/classification , Double Stranded RNA Viruses/isolation & purification , Whole Genome Sequencing , Viral Proteins/genetics , RNA, Viral/genetics , RNA-Dependent RNA Polymerase/geneticsABSTRACT
Plant-sucking insects have intricate associations with a diverse array of microorganisms to facilitate their adaptation to specific ecological niches. The midgut of phytophagous true bugs is generally structured into four distinct compartments to accommodate their microbiota. Nevertheless, there is limited understanding regarding the origins of these gut microbiomes, the mechanisms behind microbial community assembly, and the interactions between gut microbiomes and their insect hosts. In this study, we conducted a comprehensive survey of microbial communities within the midgut compartments of a bean bug Riptortus pedestris, soybean plant, and bulk soil across 12 distinct geographical fields in China, utilizing high-throughput sequencing of the 16 S rRNA gene. Our findings illuminated that gut microbiota of the plant-sucking insects predominantly originated from the surrounding soil environment, and plants also play a subordinate role in mediating microbial acquisition for the insects. Furthermore, our investigation suggested that the composition of the insect gut microbiome was probably shaped by host selection and/or microbe-microbe interactions at the gut compartment level, with marginal influence from soil and geographical factors. Additionally, we had unveiled a noteworthy dynamic in the acquisition of core bacterial taxa, particularly Burkholderia, which were initially sourced from the environment and subsequently enriched within the insect midgut compartments. This bacterial enrichment played a significant role in enhancing insect host reproduction. These findings contribute to our evolving understanding of microbiomes within the insect-plant-soil ecosystem, shedding additional light on the intricate interactions between insects and their microbiomes that underpin the ecological significance of microbial partnerships in host adaptation.
Subject(s)
Bacteria , Gastrointestinal Microbiome , RNA, Ribosomal, 16S , Soil Microbiology , Animals , RNA, Ribosomal, 16S/genetics , Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , China , Glycine max/microbiology , High-Throughput Nucleotide Sequencing , Heteroptera/microbiology , Heteroptera/physiology , Reproduction , Phylogeny , Host Microbial Interactions , Burkholderia/genetics , Burkholderia/physiology , Burkholderia/classificationABSTRACT
The brown planthopper (BPH), Nilaparvata lugens, is a significant agricultural pest capable of long-distance migration and transmission of viruses that cause severe disease in rice. In this study, we identified a novel segmented RNA virus in a BPH, and this virus exhibited a close relationship to members of a recently discovered virus lineage known as "quenyaviruses" within the viral kingdom Orthornavirae. This newly identified virus was named "Nilaparvata lugens quenyavirus 1" (NLQV1). NLQV1 consists of five positive-sense, single-stranded RNAs, with each segment containing a single open reading frame (ORF). The genomic characteristics and phylogenetic analysis support the classification of NLQV1 as a novel quenyavirus. Notably, all of the genome segments of NLRV contained the 5'-terminal sequence AUCUG. The characteristic virus-derived small interfering RNA (vsiRNA) profile of NLQV1 suggests that the antiviral RNAi pathway of the host BPH was activated in response to virus infection. These findings represent the first documented report of quenyaviruses in planthoppers, contributing to our understanding of quenyaviruses and expanding our knowledge of insect-specific viruses in planthoppers.
Subject(s)
Genome, Viral , Hemiptera , Open Reading Frames , Phylogeny , RNA Viruses , RNA, Viral , Animals , Hemiptera/virology , Genome, Viral/genetics , RNA, Viral/genetics , RNA Viruses/genetics , RNA Viruses/classification , RNA Viruses/isolation & purification , Plant Diseases/virology , Oryza/virology , Whole Genome Sequencing , RNA, Small Interfering/geneticsABSTRACT
Ivosidenib, an isocitrate dehydrogenase 1 (IDH1) inhibitor, has demonstrated clinical benefits in a pivotal study (AG120-C-001) in patients with IDH1-mutated (mIDH1) acute myeloid leukemia (AML). A registry study (CS3010-101: NCT04176393) was conducted to assess the pharmacokinetic (PK) characteristics, safety, and efficacy of ivosidenib in Chinese patients with relapsed or refractory (R/R) mIDH1 AML. Patients received ivosidenib 500 mg once daily for 28-day cycles until disease progression. Ten subjects underwent intensive PK/progressive disease (PD) assessments. All subjects had the clinical response assessed at screening, every 28 days through month 12, and then every 56 days. Between November 12, 2019, and April 2, 2021, 30 patients were enrolled; 26 (86.7%) had de novo AML and 18 (60.0%) were transfusion-dependent at baseline. Following single and repeated doses of ivosidenib, median time to maximum plasma concentration (T max) was 4.0 and 2.0 hours, respectively. The inter-individual variability of pharmacokinetic exposure was moderate to high (coefficient of variation [CV], 25%-53%). No obvious accumulation was observed after repeated doses at cycle 2 day 1. Regarding the clinical response, the CR + CRh rate was 36.7% (95% confidence interval [CI]: 19.9%-56.1%), the median duration of CR + CRh was 19.7 months (95% CI: 2.9 months-not reached [NR]), and median duration of response (DoR) was 14.3 months (95% CI: 6.4 months-NR). Consistent clinical benefits and safety of ivosidenib were consistently observed at the final data cutoff with median follow-up time 26.0 months, as compared with primary data cutoff, and the data from Chinese R/R mIDH1 AML patients were also consistent with results from pivotal study.
ABSTRACT
The advancement of bioinformatics and sequencing technology has resulted in the identification of an increasing number of new RNA viruses. This study systematically identified the RNA virome of the willow-carrot aphid, Cavariella aegopodii (Hemiptera: Aphididae), using metagenomic sequencing and rapid amplification of cDNA ends (RACE) approaches. C. aegopodii is a sap-sucking insect widely distributed in Europe, Asia, North America, and Australia. The deleterious effects of C. aegopodii on crop growth primarily stem from its feeding activities and its role as a vector for transmitting plant viruses. The virome includes Cavariella aegopodii virga-like virus 1 (CAVLV1) and Cavariella aegopodii iflavirus 1 (CAIV1). Furthermore, the complete genome sequence of CAVLV1 was obtained. Phylogenetically, CAVLV1 is associated with an unclassified branch of the Virgaviridae family and is susceptible to host antiviral RNA interference (RNAi), resulting in the accumulation of a significant number of 22nt virus-derived small interfering RNAs (vsiRNAs). CAIV1, on the other hand, belongs to the Iflaviridae family, with vsiRNAs ranging from 18 to 22 nt. Our findings present a comprehensive analysis of the RNA virome of C. aegopodii for the first time, offering insights that could potentially aid in the future control of the willow-carrot aphid.
Subject(s)
Aphids , Genome, Viral , Phylogeny , RNA Viruses , Animals , Aphids/virology , RNA Viruses/genetics , RNA Viruses/classification , RNA Viruses/isolation & purification , Virome/genetics , RNA, Viral/genetics , Metagenomics , Plant Diseases/virologyABSTRACT
Agricultural insects play a crucial role in transmitting plant viruses and host a considerable number of insect-specific viruses (ISVs). Among these insects, the white-backed planthoppers (WBPH; Sogatella furcifera, Hemiptera: Delphacidae) are noteworthy rice pests and are responsible for disseminating the southern rice black-streaked dwarf virus (SRBSDV), a significant rice virus. In this study, we analyzed WBPH transcriptome data from public sources and identified three novel viruses. These newly discovered viruses belong to the plant-associated viral family Solemoviridae and were tentatively named Sogatella furcifera solemo-like virus 1-3 (SFSolV1-3). Among them, SFSolV1 exhibited a prevalent existence in different laboratory populations, and its complete genome sequence was obtained using rapid amplification of cDNA ends (RACE) approaches. To investigate the antiviral RNA interference (RNAi) response in WBPH, we conducted an analysis of virus-derived small interfering RNAs (vsiRNAs). The vsiRNAs of SFSolV1 and -2 exhibited typical patterns associated with the host's siRNA-mediated antiviral immunity, with a preference for 21- and 22-nt vsiRNAs derived equally from both the sense and antisense genomic strands. Furthermore, we examined SFSolV1 infection and distribution in WBPH, revealing a significantly higher viral load of SFSolV1 in nymphs' hemolymph compared to other tissues. Additionally, in adult insects, SFSolV1 exhibited higher abundance in male adults than in female adults.
ABSTRACT
The efficacy of anthracycline-based chemotherapeutics, which include doxorubicin and its structural relatives daunorubicin and idarubicin, remains almost unmatched in oncology, despite a side effect profile including cumulative dose-dependent cardiotoxicity, therapy-related malignancies and infertility. Detoxifying anthracyclines while preserving their anti-neoplastic effects is arguably a major unmet need in modern oncology, as cardiovascular complications that limit anti-cancer treatment are a leading cause of morbidity and mortality among the 17 million cancer survivors in the U.S. In this study, we examined different clinically relevant anthracycline drugs for a series of features including mode of action (chromatin and DNA damage), bio-distribution, anti-tumor efficacy and cardiotoxicity in pre-clinical models and patients. The different anthracycline drugs have surprisingly individual efficacy and toxicity profiles. In particular, aclarubicin stands out in pre-clinical models and clinical studies, as it potently kills cancer cells, lacks cardiotoxicity, and can be safely administered even after the maximum cumulative dose of either doxorubicin or idarubicin has been reached. Retrospective analysis of aclarubicin used as second-line treatment for relapsed/refractory AML patients showed survival effects similar to its use in first line, leading to a notable 23% increase in 5-year overall survival compared to other intensive chemotherapies. Considering individual anthracyclines as distinct entities unveils new treatment options, such as the identification of aclarubicin, which significantly improves the survival outcomes of AML patients while mitigating the treatment-limiting side-effects. Building upon these findings, an international multicenter Phase III prospective study is prepared, to integrate aclarubicin into the treatment of relapsed/refractory AML patients.
Subject(s)
Aclarubicin , Anthracyclines , Leukemia, Myeloid, Acute , Animals , Female , Humans , Male , Aclarubicin/pharmacology , Aclarubicin/therapeutic use , Anthracyclines/therapeutic use , Antineoplastic Agents/therapeutic use , Antineoplastic Agents/pharmacology , Antineoplastic Agents/adverse effects , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/mortality , Treatment OutcomeABSTRACT
Insects constitute the largest proportion of animals on Earth and act as significant reservoirs and vectors in disease transmission. Rice thrips (Haplothrips aculeatus, family Phlaeothripidae) are one of the most common pests in agriculture. In this study, the full genome sequence of a novel Ollusvirus, provisionally named "Rice thrips ollusvirus 1" (RTOV1), was elucidated using transcriptome sequencing and the rapid amplification of cDNA ends (RACE). A homology search and phylogenetic tree analysis revealed that the newly identified virus is a member of the family Aliusviridae (order Jingchuvirales). The genome of RTOV1 contains four predicted open reading frames (ORFs), including a polymerase protein (L, 7590 nt), a glycoprotein (G, 4206 nt), a nucleocapsid protein (N, 2415 nt) and a small protein of unknown function (291 nt). All of the ORFs are encoded by the complementary genome, suggesting that the virus is a negative-stranded RNA virus. Phylogenetic analysis using polymerase sequences suggested that RTOV1 was closely related to ollusvirus 1. Deep small RNA sequencing analysis reveals a significant accumulation of small RNAs derived from RTOV1, indicating that the virus replicated in the insect. According to our understanding, this is the first report of an Ollusvirus identified in a member of the insect family Phlaeothripidae. The characterisation and discovery of RTOV1 is a significant contribution to the understanding of Ollusvirus diversity in insects.
ABSTRACT
Understanding the light adaptation of plants is critical for conservation. Platycrater arguta, an endangered deciduous shrub endemic to East Asia, possesses high ornamental and phylogeographic value. However, the weak environmental adaptability of P. arguta species has limited its general growth and conservation. To obtain a deeper understanding of the P. arguta growth conditions, we examined the leaf morphology and physiology via anatomical and chloroplast ultrastructural analyses following exposure to different natural light intensities (full light, 40%, and 10%). The findings indicated that P. arguta seedings in the 10% light intensity had significantly improved leaf morphological characteristics and specific leaf area compared to those exposed to other intensities. The net photosynthetic rate, chlorophyll (Chl) content, photosynthetic nitrogen use efficiency (PNUE), and photosynthetic phosphorus use efficiency (PPUE) exhibited marked increases at a 10% light intensity compared to both 40% light and full light intensities, whereas the light compensation point and dark respiration levels reached their lowest values under the 10% light condition. With reduced light, leaf thickness, palisade tissue, spongy tissue, and stomatal density significantly decreased, whereas the stomatal length, stomatal width, and stomatal aperture were significantly elevated. When exposed to 10% light intensity, the ultrastructure of chloroplasts was well developed, chloroplasts and starch grain size, the number of grana, and thylakoids all increased significantly, while the number of plastoglobules was significantly reduced. Relative distance phenotypic plasticity index analysis exhibited that P. arguta adapts to varying light environments predominantly by adjusting PPUE, Chl b, PNUE, chloroplast area, and the activity of PSII reaction centers. We proposed that P. arguta efficiently utilizes low light to reconfigure its energy metabolism by regulating its leaf structure, photosynthetic capacity, nutrient use efficiency, and chloroplast development.
ABSTRACT
In insects, melanism, a fundamental pigmentation process, is of significant importance in evolutionary biology due to its complex genetic foundation. We investigated the role of the RNA-binding gene Musashi (msi) in melanism in Laodelphax striatellus, a Hemiptera species. We identified a single L. striatellus msi homolog, Lsmsi, encoding a 357 amino acid protein with 2 RNA recognition motifs. RNA interference-mediated knockdown of LsMsi resulted in complete body melanism and increased cuticular permeability. Additionally, we found the involvement of G protein-coupled receptor A42 and tyrosine hydroxylase (Th) in L. striatellus melanism. Knockdown of LsTh lightened the epidermis, showing dehydration signs, while LsA42 knockdown enhanced LsTh expression, leading to melanism. Surprisingly, Lsmsi knockdown decreased both LsA42 and LsTh expression, which was expected to cause whitening but resulted in melanism. Further, we found that Lsmsi influenced downstream genes like phenoloxidase homolog LsPo and dopa decarboxylase (Ddc) homolog LsDdc in the tyrosine-mediated melanism pathway. Extending to Nilaparvata lugens and Sogatella furcifera, we demonstrated the conserved role of msi in melanism among Delphacidae. Given MSI proteins' roles in cancer and tumors in vertebrates, our study is the first to link msi in insects to Delphacidae body color melanization via the tyrosine-mediated pathway, offering fresh perspectives on the genetic basis of insect melanism and msi functions.
ABSTRACT
Carbon-sequestering microorganisms play an important role in the carbon cycle of wetland ecosystems. However, the response mechanism of carbon-sequestering microbial communities to wetland type changes and their relationship with soil carbon remain unclear. To explore these differences and identify the main influencing factors, this study selected marsh wetlands, river wetlands and lakeside wetlands around Qinghai Lake as research subjects. High-throughput sequencing was employed to analyze the functional gene cbbM of carbon-sequestering microorganisms. The results revealed that the alpha diversity of cbbM carbon-sequestering microorganisms mirrored the trend in total carbon content, with the highest diversity observed in marsh wetlands and the lowest in lakeside wetlands. The dominant bacterial phylum was Proteobacteria, with prevalent genera including Thiothrix, Acidithiobacillus, and Thiodictyon. Acidithiobacillus served as a biomarker in lakeside wetlands, while two other genera were indicative of marsh wetlands. The hierarchical partitioning analysis indicated that the diversity of cbbM carbon-fixing microorganisms was primarily influenced by the total nitrogen content, while the community structure was significantly affected by the soil total carbon content. Moreover, an increased soil temperature and humidity were found to favor the carbon fixation processes of Thiomicrospira, Thiomonas, Polaromonas, and Acidithiobacillus. In summary, changes in wetland types seriously affected the characteristics of cbbM carbon sequestration in microbial communities, and a warm and humid climate may be conducive to wetland carbon sequestration.
Subject(s)
Gene Rearrangement , Interferon Regulatory Factors , Humans , Interferon Regulatory Factors/genetics , Male , FemaleABSTRACT
A negative-strand symbiotic RNA virus, tentatively named Nilaparvata lugens Bunyavirus (NLBV), was identified in the brown planthopper (BPH, Nilaparvata lugens). Phylogenetic analysis indicated that NLBV is a member of the genus Mobuvirus (family Phenuiviridae, order Bunyavirales). Analysis of virus-derived small interfering RNA suggested that antiviral immunity of BPH was successfully activated by NLBV infection. Tissue-specific investigation showed that NLBV was mainly accumulated in the fat-body of BPH adults. Moreover, NLBV was detected in eggs of viruliferous female BPHs, suggesting the possibility of vertical transmission of NLBV in BPH. Additionally, no significant differences were observed for the biological properties between NLBV-infected and NLBV-free BPHs. Finally, analysis of geographic distribution indicated that NLBV may be prevalent in Southeast Asia. This study provided a comprehensive characterization on the molecular and biological properties of a symbiotic virus in BPH, which will contribute to our understanding of the increasingly discovered RNA viruses in insects.
Subject(s)
Hemiptera , Orthobunyavirus , RNA Viruses , Animals , Female , Phylogeny , Insecta , RNA Viruses/geneticsABSTRACT
The fruitless (fru) gene functions as a crucial "tuner" in male insect courtship behavior through distinct expression patterns. In Nilaparvata lugens, our previous research showed doublesex (dsx) influencing male courtship songs, causing mating failures with virgin females. However, the impact of fru on N. lugens mating remains unexplored. In this study, the fru homolog (Nlfru) in N. lugens yielded four spliceosomes: Nlfru-374-a/b, Nlfru-377, and Nlfru-433, encoding proteins of 374aa, 377aa, and 433aa, respectively. Notably, only Nlfru-374b exhibited male bias, while the others were non-sex-specific. All NlFRU proteins featured the BTB conserved domain, with NlFRU-374 and NlFRU-377 possessing the ZnF domain with different sequences. RNAi-mediated Nlfru or its isoforms' knockdown in nymph stages blocked wing-flapping behavior in mating males, while embryonic knockdown via maternal RNAi resulted in over 80% of males losing wing-flapping ability, and female receptivity was reduced. Nlfru expression was Nldsx-regulated, and yet courtship signals and mating success were unaffected. Remarkably, RNAi-mediated Nlfru knockdown up-regulated the expression of flightin in macropterous males, which regulated muscle stiffness and delayed force response, suggesting Nlfru's involvement in muscle development regulation. Collectively, our results indicate that Nlfru functions in N. lugens exhibit a combination of conservation and species specificity, contributing insights into fru evolution, particularly in Hemiptera species.
ABSTRACT
Integrating multiple functional components into vertically stacked heterostructures offers a prospective approach to manipulating the physicochemical properties of materials. The synthesis of vertically stacked heterogeneous noble metal oxides remains a challenge. Herein, we report a surface segregation approach to create vertically stacked amorphous Ir/Ru/Ir oxide nanosheets (NSs). Cross-sectional high-angle annular darkfield scanning transmission electron microscopy images demonstrate a three-layer heterostructure in the amorphous Ir/Ru/Ir oxide NSs, with IrOx layers located on the upper and lower surfaces, and a layer of RuOx sandwiched between the two IrOx layers. The vertically stacked heterostructure is a result of the diffusion of Ir atoms from the amorphous IrRuOx solid solution to the surface. The obtained A-Ir/Ru/Ir oxide NSs display an ultralow overpotential of 191 mV at 10 mA cm-2 toward acid oxygen evolution reaction and demonstrate excellent performance in a proton exchange membrane water electrolyzer, which requires only 1.63 V to achieve 1 A cm-2 at 60 °C, with virtually no activity decay observed after a 1300 h test.
ABSTRACT
Communication between insects and plants relies on the exchange of bioactive molecules that traverse the species interface. Although proteinic effectors have been extensively studied, our knowledge of other molecules involved in this process remains limited. In this study, we investigate the role of salivary microRNAs (miRNAs) from the rice planthopper Nilaparvata lugens in suppressing plant immunity. A total of three miRNAs were confirmed to be secreted into host plants during insect feeding. Notably, the sequence-conserved miR-7-5P is specifically expressed in the salivary glands of N. lugens and is secreted into saliva, distinguishing it significantly from homologues found in other insects. Silencing miR-7-5P negatively affects N. lugens feeding on rice plants, but not on artificial diets. The impaired feeding performance of miR-7-5P-silenced insects can be rescued by transgenic plants overexpressing miR-7-5P. Through target prediction and experimental testing, we demonstrate that miR-7-5P targets multiple plant genes, including the immune-associated bZIP transcription factor 43 (OsbZIP43). Infestation of rice plants by miR-7-5P-silenced insects leads to the increased expression of OsbZIP43, while the presence of miR-7-5P counteracts this upregulation effect. Furthermore, overexpressing OsbZIP43 confers plant resistance against insects which can be subverted by miR-7-5P. Our findings suggest a mechanism by which herbivorous insects have evolved salivary miRNAs to suppress plant immunity, expanding our understanding of cross-kingdom RNA interference between interacting organisms.
Subject(s)
Hemiptera , MicroRNAs , Oryza , Animals , RNA Interference , MicroRNAs/genetics , MicroRNAs/metabolism , Saliva , Hemiptera/physiology , Plant Immunity/genetics , Oryza/geneticsABSTRACT
Many insect pests, including the brown planthopper (BPH), undergo windborne migration that is challenging to observe and track. It remains controversial about their migration patterns and largely unknown regarding the underlying genetic basis. By analyzing 360 whole genomes from around the globe, we clarify the genetic sources of worldwide BPHs and illuminate a landscape of BPH migration showing that East Asian populations perform closed-circuit journeys between Indochina and the Far East, while populations of Malay Archipelago and South Asia undergo one-way migration to Indochina. We further find round-trip migration accelerates population differentiation, with highly diverged regions enriching in a gene desert chromosome that is simultaneously the speciation hotspot between BPH and related species. This study not only shows the power of applying genomic approaches to demystify the migration in windborne migrants but also enhances our understanding of how seasonal movements affect speciation and evolution in insects.
Subject(s)
Animal Migration , Genomics , Wind , Animals , Genomics/methods , Hemiptera/genetics , Genome, Insect , Genetics, PopulationABSTRACT
Tomato brown rugose fruit virus (ToBRFV) is a newly-emerging tobamovirus which was first reported on tomatoes in Israel and Jordan, and which has now spread rapidly in Asia, Europe, North America, and Africa. ToBRFV can overcome the resistance to other tobamoviruses conferred by tomato Tm-1, Tm-2, and Tm-22 genes, and it has seriously affected global crop production. The rapid and comprehensive transcription reprogramming of host plant cells is the key to resisting virus attack, but there have been no studies of the transcriptome changes induced by ToBRFV in tomatoes. Here, we made a comparative transcriptome analysis between tomato leaves infected with ToBRFV for 21 days and those mock-inoculated as controls. A total of 522 differentially expressed genes were identified after ToBRFV infection, of which 270 were up-regulated and 252 were down-regulated. Functional analysis showed that DEGs were involved in biological processes such as response to wounding, response to stress, protein folding, and defense response. Ten DEGs were selected and verified by qRT-PCR, confirming the reliability of the high-throughput sequencing data. These results provide candidate genes or signal pathways for the response of tomato leaves to ToBRFV infection.