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1.
J Insect Sci ; 24(3)2024 May 01.
Article in English | MEDLINE | ID: mdl-38809687

ABSTRACT

Huanglongbing (HLB), a devastating citrus disease caused by Candidatus Liberibacter asiaticus, is efficiently vectored by the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae). Tamarixia radiata (Waterston) plays a crucial role as an ectoparasitoid, preying on D. citri nymphs. By collecting and identifying headspace volatiles from fifth instar nymphs of D. citri using a gas chromatograph-mass spectrometer (GC-MS), we obtained a collection of 9 volatile compounds. These compounds were subsequently chosen to investigate the electrophysiological and behavioral responses of female T. radiata. At a concentration of 10 µg/µl, 9 compounds were compared with cis-3-hexen-1-ol (control), resulting in trans-2-nonenal inducing the highest relative electroantennogram (EAG) value, followed by hexanal, heptanal, n-heptadecane, tetradecanal, n-tetradecane, n-pentadecane, 1-tetradecanol, and 1-dodecanol. The top 5 EAG responses of female T. radiata to these compounds were further investigated through EAG dose-response experiments. The results showed positive dose-responses as concentrations increased from 0.01 to 10 µg/µl. In Y-tube olfactometer bioassays, female T. radiata exhibited a preference for specific compounds. They were significantly attracted to tetradecanal at a concentration of 10 µg/µl and trans-2-nonenal at 0.01 µg/µl, while no significant attraction was observed toward hexanal, heptanal, or n-heptadecane. Our report is the first to demonstrate that volatiles produced by D. citri nymphs attract T. radiata, which suggests that this parasitoid may utilize nymph volatiles to locate its host.


Subject(s)
Hemiptera , Nymph , Volatile Organic Compounds , Animals , Nymph/growth & development , Nymph/physiology , Hemiptera/physiology , Female , Wasps/physiology , Electrophysiological Phenomena , Behavior, Animal/drug effects , Arthropod Antennae/physiology , Arthropod Antennae/drug effects
2.
Nat Commun ; 15(1): 4426, 2024 May 24.
Article in English | MEDLINE | ID: mdl-38789507

ABSTRACT

Iron and phosphorus are essential nutrients that exist at low concentrations in surface waters and may be co-limiting resources for phytoplankton growth. Here, we show that phosphorus deficiency increases the growth of iron-limited cyanobacteria (Synechocystis sp. PCC 6803) through a PhoB-mediated regulatory network. We find that PhoB, in addition to its well-recognized role in controlling phosphate homeostasis, also regulates key metabolic processes crucial for iron-limited cyanobacteria, including ROS detoxification and iron uptake. Transcript abundances of PhoB-targeted genes are enriched in samples from phosphorus-depleted seawater, and a conserved PhoB-binding site is widely present in the promoters of the target genes, suggesting that the PhoB-mediated regulation may be highly conserved. Our findings provide molecular insights into the responses of cyanobacteria to simultaneous iron/phosphorus nutrient limitation.


Subject(s)
Bacterial Proteins , Gene Expression Regulation, Bacterial , Iron , Phosphorus , Synechocystis , Phosphorus/metabolism , Phosphorus/deficiency , Synechocystis/metabolism , Synechocystis/genetics , Iron/metabolism , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , Promoter Regions, Genetic/genetics , Seawater/microbiology , Homeostasis , Reactive Oxygen Species/metabolism
3.
J Econ Entomol ; 2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38603566

ABSTRACT

Whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) is a destructive insect pest of many crops. Rickettsia infection in different cryptic species of B. tabaci has been observed worldwide. Understanding the interactions between these 2 organisms is critical to developing Rickettsia-based strategies to control B. tabaci and thereby reduce the transmission of related vector-borne viruses. In this study, we investigated the effects of Rickettsia infection on the biological characteristics of the Middle East Asia Minor 1 (MEAM1) strain of B. tabaci through biological analysis of infected and uninfected individuals. The results of this study suggest that Rickettsia may confer fitness benefits. These benefits include increased fertility, improved survival rates, accelerated development, and resulted in female bias. We also investigated the transcriptomics impact of Rickettsia infection on B. tabaci by performing a comparative RNA-seq analysis of nymphs and adult females, both with and without the infection. Our analysis revealed 218 significant differentially expressed genes (DEGs) in infected nymphs compared to uninfected ones and 748 significant DEGs in infected female adults compared to their uninfected whiteflies. Pathway analysis further revealed that Rickettsia can affect many important metabolic pathways in whiteflies. The results suggest that Rickettsia plays an essential role in energy metabolism, and nutrient synthesis in the B. tabaci MEAM1, and depends on metabolites obtained from the host to ensure its survival. Overall, our findings suggest that Rickettsia has beneficial effects on B. tabaci and offered insights into the potential molecular mechanisms governing the interactions between Rickettsia and B. tabaci MEAM1.

4.
Bull Entomol Res ; 114(2): 210-229, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38444234

ABSTRACT

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae), is the key vector insect transmitting the Candidatus Liberibacter asiaticus (CLas) bacterium that causes the devastating citrus greening disease (Huanglongbing, HLB) worldwide. The D. citri salivary glands (SG) exhibit an important barrier against the transmission of HLB pathogen. However, knowledge on the molecular mechanism of SG defence against CLas infection is still limited. In the present study, we compared the SG transcriptomic response of CLas-free and CLas-infected D. citri using an illumine paired-end RNA sequencing. In total of 861 differentially expressed genes (DEGs) in the SG upon CLas infection, including 202 upregulated DEGs and 659 downregulated DEGs were identified. Functional annotation analysis showed that most of the DEGs were associated with cellular processes, metabolic processes, and the immune response. Gene ontology and Kyoto Encyclopaedia of Genes and Genomes enrichment analyses revealed that these DEGs were enriched in pathways involving carbohydrate metabolism, amino acid metabolism, the immune system, the digestive system, the lysosome, and endocytosis. A total of 16 DEGs were randomly selected to further validate the accuracy of RNA-Seq dataset by reverse-transcription quantitative polymerase chain reaction. This study provides substantial transcriptomic information regarding the SG of D. citri in response to CLas infection, which may shed light on the molecular interaction between D. citri and CLas, and provides new ideas for the prevention and control of citrus psyllid.


Subject(s)
Hemiptera , Salivary Glands , Transcriptome , Animals , Hemiptera/microbiology , Hemiptera/genetics , Salivary Glands/microbiology , Salivary Glands/metabolism , Plant Diseases/microbiology , Citrus/microbiology , Liberibacter
5.
mBio ; 15(3): e0244823, 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38315036

ABSTRACT

Bacterial endosymbionts play important roles in the life histories of herbivorous insects by impacting their development, survival, reproduction, and stress tolerance. How endosymbionts may affect the interactions between plants and insect herbivores is still largely unclear. Here, we show that endosymbiotic Rickettsia belli can provide mutual benefits also outside of their hosts when the sap-sucking whitefly Bemisia tabaci transmits them to plants. This transmission facilitates the spread of Rickettsia but is shown to also enhance the performance of the whitefly and co-infesting caterpillars. In contrast, Rickettsia infection enhanced plant resistance to several pathogens. Inside the plants, Rickettsia triggers the expression of salicylic acid-related genes and the two pathogen-resistance genes TGA 2.1 and VRP, whereas they repressed genes of the jasmonic acid pathway. Performance experiments using wild type and mutant tomato plants confirmed that Rickettsia enhances the plants' suitability for insect herbivores but makes them more resistant to fungal and viral pathogens. Our results imply that endosymbiotic Rickettsia of phloem-feeding insects affects plant defenses in a manner that facilitates their spread and transmission. This novel insight into how insects can exploit endosymbionts to manipulate plant defenses also opens possibilities to interfere with their ability to do so as a crop protection strategy. IMPORTANCE: Most insects are associated with symbiotic bacteria in nature. These symbionts play important roles in the life histories of herbivorous insects by impacting their development, survival, reproduction as well as stress tolerance. Rickettsia is one important symbiont to the agricultural pest whitefly Bemisia tabaci. Here, for the first time, we revealed that the persistence of Rickettsia symbionts in tomato leaves significantly changed the defense pattern of tomato plants. These changes benefit both sap-feeding and leaf-chewing herbivore insects, such as increasing the fecundity of whitefly adults, enhancing the growth and development of the noctuid Spodoptera litura, but reducing the pathogenicity of Verticillium fungi and TYLCV virus to tomato plants distinctively. Our study unraveled a new horizon for the multiple interaction theories among plant-insect-bacterial symbionts.


Subject(s)
Hemiptera , Rickettsia Infections , Rickettsia , Animals , Hemiptera/microbiology , Herbivory , Symbiosis , Plants
6.
Dalton Trans ; 53(2): 798-807, 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-38086649

ABSTRACT

At present, many researchers are focusing on trivalent lanthanide (Ln3+)-doped thermally enhanced upconversion luminescent (UCL) materials with negative thermal expansion (NTE) properties. However, selective anti-thermal quenching downshifting emissions of the activator and thermal quenching of the sensitizer in a phosphor with NTE properties are not implemented. Herein, Tb3+/Eu3+ co-doped Sc2(WO4)3 phosphors synthesized by the solid-state method are explored in selectively enhanced red emission (Eu3+:5D0 → 7F2) due to the energy-transfer efficiency from Tb3+ to Eu3+ and the promoted radiative transition probability. The selective thermally quenched green emission (Tb3+:5D4 → 7F5) is owing to the change of energy transfer from Tb3+ to Eu3+ as the temperature increased. Moreover, under ultraviolet 365 nm excitation, the thermally stimulated color emission tuned from yellow to red with the increase in temperature. Based on the radically different thermal response downshifting the luminescence of the activator and sensitizer, the luminescence intensity ratio (LIR) of non-thermally coupled levels (NTCLs) for 5D0 (Eu3+) and 5D4 (Tb3+) is adopted for optical temperature sensing. The optimal relative sensitivity of temperature sensing in the Sc2(WO4)3:25%Tb3+/3%Eu3+ sample could reach 2.94% K-1 at 347 K. All these indicate that this Sc2(WO4)3:Tb3+/Eu3+ material is a promising candidate for high-sensitivity optical temperature sensing.

7.
Plant Cell ; 36(5): 1844-1867, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38146915

ABSTRACT

Hypothetical chloroplast open reading frames (ycfs) are putative genes in the plastid genomes of photosynthetic eukaryotes. Many ycfs are also conserved in the genomes of cyanobacteria, the presumptive ancestors of present-day chloroplasts. The functions of many ycfs are still unknown. Here, we generated knock-out mutants for ycf51 (sll1702) in the cyanobacterium Synechocystis sp. PCC 6803. The mutants showed reduced photoautotrophic growth due to impaired electron transport between photosystem II (PSII) and PSI. This phenotype results from greatly reduced PSI content in the ycf51 mutant. The ycf51 disruption had little effect on the transcription of genes encoding photosynthetic complex components and the stabilization of the PSI complex. In vitro and in vivo analyses demonstrated that Ycf51 cooperates with PSI assembly factor Ycf3 to mediate PSI assembly. Furthermore, Ycf51 interacts with the PSI subunit PsaC. Together with its specific localization in the thylakoid membrane and the stromal exposure of its hydrophilic region, our data suggest that Ycf51 is involved in PSI complex assembly. Ycf51 is conserved in all sequenced cyanobacteria, including the earliest branching cyanobacteria of the Gloeobacter genus, and is also present in the plastid genomes of glaucophytes. However, Ycf51 has been lost from other photosynthetic eukaryotic lineages. Thus, Ycf51 is a PSI assembly factor that has been functionally replaced during the evolution of oxygenic photosynthetic eukaryotes.


Subject(s)
Bacterial Proteins , Open Reading Frames , Photosystem I Protein Complex , Synechocystis , Photosystem I Protein Complex/metabolism , Photosystem I Protein Complex/genetics , Synechocystis/genetics , Synechocystis/metabolism , Open Reading Frames/genetics , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , Chloroplasts/metabolism , Photosynthesis/genetics , Thylakoids/metabolism , Photosystem II Protein Complex/metabolism , Photosystem II Protein Complex/genetics , Mutation
8.
Hypertension ; 81(2): 372-382, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38116660

ABSTRACT

BACKGROUND: The pathogenesis of chronic thromboembolic pulmonary hypertension (CTEPH) is multifactorial and growing evidence has indicated that hematological disorders are involved. Clonal hematopoiesis of indeterminate potential (CHIP) has recently been associated with an increased risk of both hematological malignancies and cardiovascular diseases. However, the prevalence and clinical relevance of CHIP in patients with CTEPH remains unclear. METHODS: Using stepwise calling on next-generation sequencing data from 499 patients with CTEPH referred to 3 centers between October 2006 and December 2021, CHIP mutations were identified. We associated CHIP with all-cause mortality in patients with CTEPH. To provide insights into potential mechanisms, the associations between CHIP and inflammatory markers were also determined. RESULTS: In total, 47 (9.4%) patients with CTEPH carried at least 1 CHIP mutation at a variant allele frequency of ≥2%. The most common mutations were in DNMT3A, TET2, RUNX1, and ASXL1. During follow-up (mean, 55 months), deaths occurred in 22 (46.8%) and 104 (23.0%) patients in the CHIP and non-CHIP groups, respectively (P<0.001, log-rank test). The association of CHIP with mortality remained robust in the fully adjusted model (hazard ratio, 2.190 [95% CI, 1.257-3.816]; P=0.006). Moreover, patients with CHIP mutations showed higher circulating interleukin-1ß and interleukin-6 and lower interleukin-4 and IgG galactosylation levels. CONCLUSIONS: This is the first study to show that CHIP mutations occurred in 9.4% of patients with CTEPH are associated with a severe inflammatory state and confer a poorer prognosis in long-term follow-up.


Subject(s)
Cardiovascular Diseases , Hypertension, Pulmonary , Humans , Clonal Hematopoiesis , Hypertension, Pulmonary/etiology , Hypertension, Pulmonary/genetics , Hematopoiesis/genetics , Cardiovascular Diseases/genetics , Mutation
9.
J Hazard Mater ; 465: 133244, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38147756

ABSTRACT

Cadmium (Cd) is a heavy metal that is of great concern in agroecosystems due to its toxicity to plants, herbivores, carnivores, and human beings. The current study evaluated the allocation and bioaccumulation of Cd from soil to cotton plants, cotton plants to herbivore pests, and herbivorous pests to a natural enemy predator. When soil was spiked with 100 mg/kg Cd, results demonstrated that cotton roots accumulated more Cd than the stems and leaves. The bioaccumulation of Cd was less in 4th instar larvae, pupa, and adults of Serangium japonicum than in Bemisia tabaci adults. The bioaccumulation in S. japonicum elongated the immature development period and reduced adult longevity, oviposition days, fertility, and total pre-oviposition duration. The net reproduction of S. japonicum was also reduced, as was female mature weight and feeding potential; as a result, Cd exposure could reduce the future population size compared to uncontaminated populations. There was decreased activity of the antioxidant enzymes (SOD, CAT, and POD) and energy-conserving lipids (glycogen, triglyceride, and total cholesterol) in Cd-contaminated S. japonicum compared to controls. The detoxifying enzyme activity of GST and P450 increased while AChE activity did not change. The qRT-PCR research showed that SOD1, CAT, POD, glycogen, and triglyceride gene expression was higher than in controls, whereas detoxification gene expression did not change. Our results indicate that Cd exposure has a physiological trade-off between its adverse effects on life history traits and elevated detoxification and antioxidation of S. japonicum, which could result from gene expression alteration. Further studies are needed to assess whether Cd exposure causes irreversible DNA damage in S. japonicum.


Subject(s)
Coleoptera , Hemiptera , Humans , Animals , Female , Coleoptera/physiology , Cadmium , Antioxidants , Glycogen , Soil , Triglycerides
10.
ACS Appl Mater Interfaces ; 15(39): 45764-45773, 2023 Oct 04.
Article in English | MEDLINE | ID: mdl-37726198

ABSTRACT

Li metal batteries applying Li-rich, Mn-rich (LMR) layered oxide cathodes present an opportunity to achieve high-energy density at reduced cell cost. However, the intense oxidizing and reducing potentials associated with LMR cathodes and Li anodes present considerable design challenges for prospective electrolytes. Herein, we demonstrate that, somewhat surprisingly, a properly designed localized-high-concentration electrolyte (LHCE) based on ether solvents is capable of providing reversible performance for Li||LMR cells. Specifically, the oxidative stability of the LHCE was found to heavily rely on the ratio between salt and solvating solvent, where local-saturation was necessary to stabilize performance. Through molecular dynamics (MD) simulations, this behavior was found to be a result of aggregated solvation structures of Li+/anion pairs. This LHCE system was found to produce significantly improved LMR cycling (95.8% capacity retention after 100 cycles) relative to a carbonate control as a result of improved cathode-electrolyte interphase (CEI) chemistry from X-ray photoelectron spectroscopy (XPS), and cryogenic transmission electron microscopy (cryo-TEM). Leveraging this stability, 4 mAh cm-2 LMR||2× Li full cells were demonstrated, retaining 87% capacity after 80 cycles in LHCE, whereas the control electrolyte produced rapid failure. This work uncovers the benefits, design requirements, and performance origins of LHCE electrolytes for high-voltage Li||LMR batteries.

11.
Ecotoxicol Environ Saf ; 263: 115300, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37494735

ABSTRACT

Ultraviolet-A (UV-A) radiation directly impacts the growth and spread of Bemisia tabaci. However, the mechanistic pathways of this phenomenon remain unknown. We analyzed B. tabaci transcriptome data after exposure to UV-A radiation for 6 h. The 453 genes were identified whose expression were significantly altered in response to the stress induced by UV-A irradiation. Forty genes were up-regulated, while 413 genes were down-regulated. Enrichment analysis using GO, KEGG, and Genomes databases revealed that the DEGs play key roles in antioxidation and detoxification, protein turnover, metabolic, developmental processes, and immunological response. Among the gene families involved in detoxification, shock, and development, down-regulated DEGs in transcriptional factor gene families were significantly greater than those up-regulated DEGs. Our findings demonstrated that exposure to UV-A stress can suppress immunity and affect the growth and biological parameters of B. tabaci by altering gene regulation. These results suggest a potential utility of UV-A stress in managing B. tabaci under greenhouse conditions.


Subject(s)
Gene Expression Profiling , Hemiptera , Animals , Gene Expression Profiling/methods , Transcriptome , Gene Expression Regulation , Hemiptera/genetics , Hemiptera/metabolism
12.
Inorg Chem ; 62(24): 9518-9527, 2023 Jun 19.
Article in English | MEDLINE | ID: mdl-37269358

ABSTRACT

Thermal quenching (TQ) is still a critical challenge for lanthanide (Ln3+)-doped luminescent materials. Herein, we report the novel negative thermal expansion nonhygroscopic phosphor ZrSc(WO4)2PO4:Yb3+/Er3+. Upon excitation with a 980 nm laser, a simultaneous thermal enhancement is realized on upconversion (UC) and downshifting (DS) emissions from room temperature to 573 K. In situ temperature-dependent X-ray diffraction and photoluminescence dynamics are used to reveal the luminescence mechanism in detail. The coexistence of the high energy transfer efficiency and the promoted radiative transition probability can be responsible for the thermally enhanced luminescence. On the basis of the luminescence intensity ratio of thermally coupled energy levels 2H11/2 and 4S3/2 at different temperatures, the relative and absolute sensitivities of the targeted samples reach 1.10% K-1 and 1.21% K-1, respectively, and the low-temperature uncertainty is approximately 0.1-0.4 K on the whole temperature with a high repeatability (98%). Our findings highlight a general approach for designing a hygro-stable, thermostable, and highly efficient Ln3+-doped phosphor with UC and DS luminescence.

13.
J Econ Entomol ; 116(4): 1276-1285, 2023 08 10.
Article in English | MEDLINE | ID: mdl-37279557

ABSTRACT

The whitefly, Bemisia tabaci, is a destructive and invasive pest of many horticultural plants including poinsettia (Euphorbia pulcherrima). Outbreaks of B. tabaci cause serious damage by direct feeding on phloem sap, and spreading 100+ plant viruses to crops. Bemisia tabaci were observed more frequently on green than red poinsettia leaves, and the factors responsible for this are unknown. Here, we investigated the development rate, survivorship, fecundity of B. tabaci feeding on green versus red leaves, as well as the leaves' volatiles, trichome density, anthocyanin content, soluble sugars, and free amino acids. Compared to red leaves, B. tabaci on green leaves showed increased fecundity, a higher female sex ratio, and survival rate. The green color alone was more attractive to B. tabaci than red. Red leaves of poinsettia contained more phenol, and panaginsene in their volatiles. Alpha-copaene and caryophyllene were more abundant in the volatiles of poinsettia green leaves. Leaf trichome density, soluble sugars and free amino acids were higher in green than red leaves of poinsettia, anthocyanin was lower in green than red leaves. Overall, green leaves of poinsettia were more susceptible and attractive to B. tabaci. The morphological and chemical variation between red and green leaves also differed; further investigation may reveal how these traits affect B. tabaci's responses.


Subject(s)
Euphorbia , Hemiptera , Animals , Amino Acids/analysis , Anthocyanins/analysis , Plant Leaves/chemistry , Trichomes , Male , Female
14.
Mater Horiz ; 10(9): 3499-3506, 2023 Aug 29.
Article in English | MEDLINE | ID: mdl-37255034

ABSTRACT

Laser-driven liquid crystal displays (LCDs) comprising metal halide perovskites (MHPs) as the blue-to-green/red color converters are at the forefront of ongoing intense research on the development and improvement of display devices. However, the inferior high photoluminescence quantum yield (PLQY) of MHPs under the excitation of high-power blue light and photoluminescence deterioration at high temperatures remain major concerns. Herein, we design a kind of octylamine-modified MHP via binding energy engineering, and the synthesized materials show PLQY of 97.6% under the excitation of a blue laser at 450 nm. Meanwhile, this design endows a structural self-healing ability to achieve a high PLQY and luminescence stability under high temperature (90 °C) and high flux excitation (386 mW cm-2). The blue light-excitable MHPs with a near unity PLQY, strong stability, and low PLQY deterioration are further encapsulated into a laser-driven LCD device. This prototype demonstrates excellent color gamut (132% NTSC, 98% Rec. 2020), illuminance intensity (>10 000 lux), and energy consumption (47.5% of commercial consumption), and hence is expected to be beneficial for the reduction of energy consumption in backlight display devices, particularly in large-screen outdoor displays.

15.
J Phys Chem Lett ; 14(19): 4575-4582, 2023 May 18.
Article in English | MEDLINE | ID: mdl-37162124

ABSTRACT

Li-rich layered oxides (LLOs) are regarded as one of the most desirable cathode materials due to their high specific capacity. Nevertheless, the irreversible oxygen release associated with low oxygen stability prevents their widespread application. Herein, an improved oxygen redox reversibility was achieved by constructing Ni2+-O2--Ni2+ configurations. Superconducting Quantum Interference Device (SQUID) magnetometry measurements are used to track the evolution of the Ni2+-O2--Ni2+ configuration during the electrochemical process. The strongest 180° superexchange interaction in the Ni2+-O2--Ni2+ configuration, derived from the inevitable Li/Ni mixing in LLOs, regulates the local structure to form the ferrimagnetic (FiM) structural units. Consequently, the FiM structural units prevent the irreversible oxygen release and endow LLOs with high initial Coulombic efficiency (ICE). This work emphasizes the importance of the Ni2+-O2--Ni2+ configuration for LLOs with high reversible capacity and proposes a synthesis approach to modulate the amount of FiM structural units.

16.
Plant Physiol ; 192(4): 2640-2655, 2023 08 03.
Article in English | MEDLINE | ID: mdl-37070859

ABSTRACT

Orange carotenoid protein (OCP) is a photoactive protein that participates in the photoprotection of cyanobacteria. There are 2 full-length OCP proteins, 4 N-terminal paralogs (helical carotenoid protein [HCP]), and 1 C-terminal domain-like carotenoid protein (CCP) found in Nostoc flagelliforme, a desert cyanobacterium. All HCPs (HCP1 to 3 and HCP6) from N. flagelliforme demonstrated their excellent singlet oxygen quenching activities, in which HCP2 was the strongest singlet oxygen quencher compared with others. Two OCPs, OCPx1 and OCPx2, were not involved in singlet oxygen scavenging; instead, they functioned as phycobilisome fluorescence quenchers. The fast-acting OCPx1 showed more effective photoactivation and stronger phycobilisome fluorescence quenching compared with OCPx2, which behaved differently from all reported OCP paralogs. The resolved crystal structure and mutant analysis revealed that Trp111 and Met125 play essential roles in OCPx2, which is dominant and long acting. The resolved crystal structure of OCPx2 is maintained in a monomer state and showed more flexible regulation in energy quenching activities compared with the packed oligomer of OCPx1. The recombinant apo-CCP obtained the carotenoid pigment from holo-HCPs and holo-OCPx1 of N. flagelliforme. No such carotenoid transferring processes were observed between apo-CCP and holo-OCPx2. The close phylogenetic relationship of OCP paralogs from subaerial Nostoc species indicates an adaptive evolution toward development of photoprotection: protecting cellular metabolism against singlet oxygen damage using HCPs and against excess energy captured by active phycobilisomes using 2 different working modes of OCPx.


Subject(s)
Nostoc , Phycobilisomes , Phylogeny , Phycobilisomes/metabolism , Singlet Oxygen , Bacterial Proteins/metabolism , Carotenoids/metabolism , Nostoc/genetics , Nostoc/metabolism
17.
Insects ; 14(4)2023 Apr 21.
Article in English | MEDLINE | ID: mdl-37103216

ABSTRACT

Wolbachia and Rickettsia are bacterial endosymbionts that can induce a number of reproductive abnormalities in their arthropod hosts. We screened and established the co-infection of Wolbachia and Rickettsia in Bemisia tabaci and compared the spatial and temporal distribution of Wolbachia and Rickettsia in eggs (3-120 h after spawning), nymphs, and adults of B. tabaci by qPCR quantification and fluorescent in situ hybridization (FISH). The results show that the titer of Wolbachia and Rickettsia in the 3-120 h old eggs showed a "w" patterned fluctuation, while the titers of Wolbachia and Rickettsia had a "descending-ascending descending-ascending" change process. The titers of Rickettsia and Wolbachia nymphal and the adult life stages of Asia II1 B. tabaci generally increased with the development of whiteflies. However, the location of Wolbachia and Rickettsia in the egg changed from egg stalk to egg base, and then from egg base to egg posterior, and finally back to the middle of the egg. These results will provide basic information on the quantity and localization of Wolbachia and Rickettsia within different life stages of B. tabaci. These findings help to understand the dynamics of the vertical transmission of symbiotic bacteria.

18.
Front Cell Infect Microbiol ; 13: 1121186, 2023.
Article in English | MEDLINE | ID: mdl-36949814

ABSTRACT

Background: Wolbachia is the most abundant bacterial endosymbiont among insects. It can play a prominent role in the development, reproduction and immunity of its given insect host. To date, Wolbachia presence is well studied within aphids, whiteflies and planthoppers, but relatively few studies have investigated its presence in psyllids. Methods: Here, the infection status of Wolbachia in five species of psyllid, including Asian citrus psyllid Diaphorina citri and longan psyllid Cornegenapsylla sinica was investigated. The phylogenetic relationships of different Wolbachia lines and their infection density and patterns in D. citri and C. sinica from different countries was also examined. Results: The infection rates of Wolbachia in D. citri and C. sinica were both 100%, and their sequencing types are ST173 and ST532 respectively. Phylogenetic analysis revealed that the Wolbachia lines in D. citri and C. sinica both belong to the Con subgroup of Wolbachia supergroup B. In addition, Wolbachia displayed a scattered localization pattern in the 5th instar nymphs and in the reproductive organs of both D. citri and C. sinica but differed in other tissues; it was highest in the midgut, lowest in the salivary glands and medium in both the testes and ovaries. Conclusion: Our findings assist in further understanding the coevolution of Wolbachia and its psyllid hosts. Given that Wolbachia could play an important role in insect pest control and pathogen transmission inhibition, our findings may also provide new insights for development of control strategies for D. citri and C. sinica.


Subject(s)
Citrus , Hemiptera , Wolbachia , Animals , Hemiptera/microbiology , Wolbachia/genetics , Phylogeny , Citrus/microbiology
20.
Ecotoxicol Environ Saf ; 251: 114519, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36634478

ABSTRACT

Blue light with a wavelength of 400-470 nm is the composition of the visible light. However, in recent years, blue light contributed the most significance to light pollution due to the artificial light at night. Previously, we have demonstrated that the Asian citrus psyllid (ACP), Diaphorina citri, an important pest in citrus production, has significant positive phototaxis with a light-emitting diode light of 400 nm. In this study, ACP with positive phototactic behavior to 400 nm light (PH) and non-phototactic behavior to 400 nm light (NP) were collected, individually. Transcriptome dynamics of head tissues of PH and NP groups were captured by using RNA-sequencing technology, respectively. Forty-three to 46 million clean reads with high-quality values were obtained, and 1773 differential expressed genes (DEGs) were detected. Compared with the NP group, there were 841 up-regulated DEGs and 932 down-regulated DEGs in the PH group. Eight pathways were significantly enriched in the PH group in the KEGG database, while 43 up-regulated pathways and 25 down-regulated pathways were significantly enriched in the PH group in the GO database. The DGE approach was reliable validated by real time quantitative PCR. Results indicated that the blue light acted as an abiotic stress causing physiological and biochemical responses such as oxidative stress, protein denaturation, inflammation and tumor development in ACPs. Additionally, the light was absorbed by photoreceptors of ACPs, and converted into electrical signal to regulate neuromodulation. This study provides basic information for understanding the molecular mechanisms of ACP in response to blue light and provides a reference for further studies to elucidate phototactic behavior.


Subject(s)
Citrus , Hemiptera , Animals , Phototaxis , Hemiptera/genetics , Hemiptera/metabolism , Transcriptome , Light , Citrus/genetics , Brain
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