Artificial Nucleic Acid Tractor-Directed Simultaneous Depletion of Oncogenic Membrane Proteins Without Hijacking Proteolysis-Specific Actuator

Targeted protein degradation(TPD)is an emerging tool for degrading proteins of interest,which affords an attractive modality for cancer therapy.However,the present TPD technologies must engage a proteolysis-specific actuator to initiate degradation of targeted proteins in the proteasome or lysosome.Herein,we report an artificial tractor that can induce endocytosis-mediated protein depletion without hijacking a proteolysis-specific actuator.In this design,bispecific aptamer chimeras(BSACs)are established,which can bridge human epidermal growth factor receptor 2(ErbB-2),an important biomarker in a common important biomarker in cancer,with membrane proteins of interest.Taking advantage of the property of aptamer-induced endocytosis and digestion of ErbB-2,another membrane protein is translocated into the lysosome in a hitchhike-like manner,resulting in lysosomal proteolysis along with ErbB-2.This strategy frees the TPD from the fundamental limitation of proteolysis-specific actuator and allows simultaneous regulation of the quantity and function of two oncogenic receptors in a cell-type-specific manner,expanding the application scope of TPD-based therapeutics.

Juvenile hormone acts on male accessory gland function via regulating L-asparaginase expression and triacylglycerol mobilization in Aedes aegypti

Hormones control the reproductive development of Aedes aegypti mosquitoes.The adult male reproductive process and mating behavior require adequate nutrients and energy.Understanding the molecular mechanism linking hormones,energy metabolism,and reproduction in male mosquitoes is important.In this study,we found that the size of the male accessory gland,an essential part of the male reproductive system,gradually increased after eclosion.However,it was significantly reduced in male mosquitoes deficient in methoprene-tolerant(Met),the receptor of juvenile hormone.Likewise,egg hatchability of females that mated with Met-depleted males showed the same downward trend.The mRNA level of the gene encoding accessory gland protein,l-asparaginase(ASNase),was reduced in Met dsRNA-treated males.Electrophoretic mobility shift assay and quantitative reverse transcription-PCR results revealed that Met was capable of binding directly to the promoter of ASNase and activated its transcription.RNA interference of ASNase in males resulted in the reduction of egg hatchability of the females with which they mated.These results showed that Met influenced the fecundity of male mosquitoes by directly upregulating the expression of the ASNase gene.Moreover,the levels of triacylglycerol and the sizes of lipid droplets were decreased by 72-78 h after eclosion in the fat body cells,whereas both of them increased in Met-depleted male mosquitoes,indicating that Met knockdown reduced lipid catabolism.These data demonstrate that Met might influence the egg hatchability of females by regulating lipid metabolism and the development of the male accessory gland in male mosquitoes.

Rho 1 participates in parasitoid wasp eggs maturation and host cellular immunity inhibition

Endoparasitoid wasps introduce venom into their host insects during the egglaying stage.Venom proteins play various roles in the host physiology,development,immunity,and behavior manipulation and regulation.In this study,we identified a venom protein,MmRhol,a small guanine nucleotide-binding protein derived from ovary in the endoparasitoid wasp Microplitis mediator and found that knockdown of its expression by RNA interference caused down-regulation of vitellogenin and juvenile hormone,egg production,and cocoons formation in the female wasps.We demonstrated that MmRho1 entered the cotton bollworm's(host)hemocytes and suppressed cellular immune responses after parasitism using immunofluorescence staining.Furthermore,wasp MmRhol interacted with the cotton bollworm's actin cytoskeleton rearrangement regulator diaphanous by yeast 2-hybrid and glutathione s-transferase pull-down.In conclusion,this study indicates that MmRho1 plays dual roles in wasp development and the suppression of the host insect cellular immune responses.

Infection and transovarial transmission of severe fever with thrombocytopenia syndrome virus in Rhipicephalus sanguineus in Hainan Island,China

Dear Editor,Severe fever with thrombocytopenia syndrome(SFTS)is an emerging human disease with high mortality rates of up to 30%(Yu et al.2011;Li et al.2018,2021).The increasing incidence of SFTS led to great concern for public health in East Asia(Zhu et al.2019;Miao et al.2020).SFTS is caused by SFTS virus(SFTSV),a newly discovered tick-borne bunyavirus in the family Phenuiviridae.SFTSV was first identified in China in 2009(Yu et al.2011)and subsequently in South Korea(Kim et al.2013)and Japan(Takahashi et al.2014).

Comparative analysis of peptidoglycan recognition proteins in endoparasitoid wasp Microplitis mediator

Peptidoglycan recognition proteins （PGRPs） are a family of innate immune receptors that specifically recognize peptidoglycans （PGNs） on the surface of a number of pathogens. Here, we have identified and characterized six PGRPs from endoparasitoid wasp, Microplitis mediator （MmePGRPs）. To understand the roles of PGRPs in parasitoid wasps, we analyzed their evolutionary relationship and orthology, expression profiles during different developmental stages, and transcriptional expression following infection with Gram-positive and -negative bacteria and a fungus. MmePGRP-S1 was significantly induced in response to pathogenic infection. This prompted us to evaluate the effects of RNA interference mediated gene specific knockdown ofMmePGRP-S1. The knockdown of MmePGRP-S1 （iMmePGRP-S1） dramatically affected wasps＇ survival following challenge by Micrococcus luteus, indicating the involvement of this particular PGRP in immune responses against Gram-positive bacteria. This action is likely to be mediated by the Toll pathway, but the mechanism remains to be determined. MmePGRP-S 1 does not play a significant role in anti-fungal immunity as indicated by the survival rate of iMmePGRP-S wasps. This study provides a comprehensive characterization of PGRPs in the economically important hymenopteran species M. mediator.

Identification and temporal expression profiles of cuticular proteins in the endoparasitoid wasp,Microplitis mediator

Recently,parasitoid wasp species Microplitis mediator has evoked increasing research attention due to its possible use in the control of Lepidoptera insects.Because insect development involves changes in cuticle composition,identification and expression analysis of M.mediator cuticular proteins may clarify the mechanisms involved in parasite development processes.We found 70 cuticular proteins from the M.mediator transcrip-tome and divided them into seven distinct families.Expression profiling indicated that most of these cuticular protein genes have expression peaks specific for one particular developmental stage of M.mediator.Eggs and pupae have the highest number of tran-scriptionally active cuticular protein genes(47 and 52 respectively).Only 12 of these genes maintained high expression activity during late larval development.Functional analysis of two larval proteins,MmCPR3 and MmCPR 14,suggested their important role in the proper organization of the cuticle layers of larvac.During M.mediator larval development,normal cuticle formation can be supported by a limited number of cuticular proteins.

Comparative analysis of C-type lectin domain proteins in the ghost moth, Thitarodes xiaojinensis (Lepidoptera: Hepialidae)

Insects have a large family of C-type lectins involved in cell adhesion, pathogen recognition and activation of immune responses. In this study, 32 transcripts encoding C-type lectin domain proteins (CTLDPs) were identified from the Thitarodes xiaojinensis transcriptome. According to their domain structures, six CTLDPs with one carbohydraterecognition domain (CRD) were classified into the CTL-S subfamily. The other 23 CTLDPs with two CRDs were grouped into the immulectin (IML) subfamily. The remaining three with extra regulatory domains were sorted into the CTL-X subfamily. Phylogenetic analysis showed that CTL-S and CTL-X members from different insects could form orthologous groups. In contrast, no T. xiaojinensis IML orthologues were found in other insects. Remarkable lineage-specific expansion in this subfamily was observed reflecting that these CTLDPs, as important receptors, have evolved diversified members in response to a variety of microbes. Prediction of binding ligands revealed that T. xiaojinensis, a coldadapted species, conserved the ability of CRDs to combine with Ca^2+ to keep its receptors from freezing. Comparative analysis of induction of CTLDP genes after different immune challenges indicated that IMLs might play critical roles in immune defenses. This study examined T. xiaojinensis CTLDPs and provides a basis for further studies of their characteristics.

Comparative analysis of the Monochamus alternatus immune system

The pine sawyer beetle, Monochamus alternatus, is regarded as a notorious for- est pest in Asia, vectoring an invasive pathogenic nematode, Bursaphelenchus xylophilus, which is known to cause pine wilt disease. However, little sequence information is available for this vector beetle. This hampered the research on its immune system. Based on the transcriptome of M. alternatus, we have identified and characterized 194 immunity-related genes in M. alternatus, and compared them with homologues molecules from other species known to exhibit immune responses against invading microbes. The lower number of puta- tive immunity-related genes in M. alternatus were attributed to fewer C-type lectin, serine protease （SP） and anti-microbial peptide （AMP） genes. Phylogenetic analysis revealed that M. alternatus had a unique recognition gene, galectin3, orthologues of which were not identified in Tribolium castaneum, Drosophila melanogastor, Anopheles gambiae and Apis mellifera. This suggested a lineage-specific gene evolution for coleopteran insects. Our study provides the comprehensive sequence resources of the immunity-related genes ofM. alternatus, presenting valuable information for better understanding of the molecular mechanism of innate immunity processes in M. alternatus against B. xylophilus.

Near-infrared photothermal release of hydrogen sulfide from nanocomposite hydrogels for anti-inflammation applications

A novel near-infrared light photothemal-activated H2S-donating nanocomposite hydrogel was developed,through combination of a thermo-labile H2S donor and photothermal nanoparticles in agarose hydrogel.The polyethylenimine dithiocarbamate polymer,a thermo-labile compound,was synthesized as a novel H2S donor.The combination of a thermo-labile hydrogen sulfide donor and photothermal nanoparticles enabled the generation of H2S in agarose hydrogel upon irradiation with near-infrared light.The ability to modulate the photoirradiation for controlled generation and spatiotemporally release of H2S are its specific advantages.This photothermal spatiotemporally controlled H2S-releasing strategy was successfully applied to anti-inflammation treatment in a rat model,demonstrating its utility as a novel H2S-based therapeutic approach.

Microbiota modulates gut immunity and promotes baculovirus infection in Helicoverpa armigera

Baculoviruses are natural enemies of agricultural and forest insect pests and play an important role in biological pest control.Oral infection by baculovirus in the insect midgut is necessary for establishing systemic infection and eventually killing the insect.Since the insect midgut continuously encounters microbiota,the gut microbiota could affect baculovirus infection.Here,we demonstrated that gut microbiota modulates immune responses and promotes baculovirus infection in the cotton bollworm,Helicoverpa armigera.After oral infection,numerous host immunity-related genes including genes encoding Toll and immune deficiency(IMD)pathway components were upregulated in the midgut.Elimination of the gut microbiota significantly increased the resistance to viral infection in H.armigera.Quantitative real-time reverse transcription polymerase chain reaction and proteomic analysis showed that downregulation of the antiviral factor prophenoloxidase(PPO)could be mediated by microbiota during infection.It implied that midgut microbiota diminishes the expression of PPO to facilitate viral infection in H.armigera.Our findings revealed that the microbiota plays an important role in modulating the resistance of H.armigera to baculovirus infection,providing new insights in applying biopesticide.

Differential immune responses of Monochamus alternatus against symbiotic and entomopathogenic fungi

Monochamus alternates,the main vector beetles of invasive pinewood nematode,has established a symbiotic relationship with a native ectotrophic fungal symbiont,Sporothrix sp.1,in China.The immune response ofM.alternates to S.sp.1 in the coexistence of beetles and fungi is,however,unknown.Here,we report that immune responses ofM.alternates pupae to infection caused by ectotrophic symbiotic fungus S.sp.1 and entomopathogenic fungus Beauveria bassiana differ significantly.The S.sp.1 did not kill the beetles while B.bassiana killed all upon injection.The transcriptome results showed that the numbers of differentially expressed genes in M.alternates infected with S.sp.1 were 2-fold less than those infected with B.bassiana at 48 hours post infection.It was noticed that Toll and IMD pathways played a leading role in the beetle's immune system when infected by symbiotic fungus,but upon infection by entomopathogenic fungus,only the Toll pathway gets triggered actively.Furthermore,the beetles could tolerate the infection of symbiotic fungi by retracing their Toll and IMD pathways at 48 h.This study provided a comprehensive sequence resource ofM.alternates transcriptome for further study of the immune interactions between host and associated fungi.

A dsDNA-lighted fluorophore for monitoring protein-ligand interaction through binding-mediated DNA protection

Because of their important roles in cellular functions, life activities, drug screening, and disease treatment, the development of efficient methods for monitoring protein-ligand interaction is essential. In this study, inspired by our previous studies on DNA conformation-selective fluorescent indicators, we developed a new sensing platform for monitoring protein-ligand interaction and detecting protein activity based on binding-mediated DNA protection and the dsDNA-lighted fluorophore, ethyl-4-[3,6-bis(1-methyl-4-vinylpyridium iodine)-9 H-carbazol-9-yl)] butanoate(EBCB). The ligand was purposefully linked to the 3?-terminal of a hairpin DNA probe to selectively bind with the target protein and protect the DNA from cleavage by exonuclease III. By virtue of EBCB's outstanding capacity to discriminate DNA conformation, the protein-ligand interaction could be effectively monitored through a fluorescence change in EBCB. A high fluorescence signal was detected when the hairpin DNA was protected in the presence of the target protein, whereas a much lower signal was observed in the presence of nontarget proteins.Our results demonstrated that the proposed strategy had high potential, such as high selectivity and relatively high sensitivity, for monitoring protein-ligand interaction and detecting protein activity. We believe these results will pave the way for applying dsDNA-lighted fluorophore EBCB as an effective signal transducer for DNA conformation transformation-mediated biochemical sensing.

Avian influenza viruses suppress innate immunity by inducingtrans-transcriptional readthrough via SSU72

Innate immunity plays critical antiviral roles. The highly virulent avian influenza viruses (AIVs) H5N1, H7N9, and H5N6 can betterescape host innate immune responses than the less virulent seasonal H1N1 virus. Here, we report a mechanism by whichtranscriptional readthrough (TRT)-mediated suppression of innate immunity occurs post AIV infection. By using cell lines, mouselungs, and patient PBMCs, we showed that genes on the complementary strand (“trans” genes) influenced by TRT were involved inthe disruption of host antiviral responses during AIV infection. The trans-TRT enhanced viral lethality, and TRT abolishmentincreased cell viability and STAT1/2 expression. The viral NS1 protein directly bound to SSU72, and degradation of SSU72 inducedTRT. SSU72 overexpression reduced TRT and alleviated mouse lung injury. Our results suggest that AIVs infection induce TRT byreducing SSU72 expression, thereby impairing host immune responses, a molecular mechanism acting through the NS1-SSU72-trans-TRT-STAT1/2 axis. Thus, restoration of SSU72 expression might be a potential strategy for preventing AIV pandemics.

Target-triggered hairpin-free chain-branching growth of DNA dendrimers for contrast-enhanced imaging in living cells by avoiding signal dispersion

The development of amplification strategies is one of the central challenges for detection of lowabundance targets. One-to-many(1:M) amplification strategies in which one target lights many signal probes, has improved the detection sensitivity in bulk solution, but with discounted contrast in cell imaging, because the lighted probes are dissociative and dispersible. In this work, a one-to-large(1:L) signaling mechanism, in which the lighted probes were orderly connected to each other, was conceptually proposed to enhance the contrast in cell imaging by avoiding signal dispersion in amplification. Accordingly,target-triggered hairpin-free chain-branching assembly(HFCBA) holds great potential to implement the1:L mechanism, but using it in cell imaging has yet to be demonstrated. As a proof of concept, a group of probes were first programmed to implement mi RNA-21-triggered HFCBA. After transfection of probes,gradually-growing signal flares in cells were monitored along with the growth of DNA dendrimers;and the in situ fluorescence accumulation in HFCBA resulted in highly-enhanced contrast to the surrounding by avoiding signal dispersion in amplification. The contrast-enhanced imaging with signal amplification is significant for biological analysis and molecular medicine. We expect the 1:L mechanism will provide a new thought for high-performance imaging of biomarkers in cells.

Improved nitrogen removal in dual-contaminated surface water by photocatalysis

River waters in China have dual contamination by nutrients and recalcitrant organic compounds. In principle, the organic compotmds could be used to drive denitrification of nitrate, thus arresting eutrophication potential, if the recalcitrant organics could be made bioavailable. This study investigated the potential to make the recalcitrant organics bioavailable through photocatalysis. Batch denitrification tests in a biofilm reactor demonstrated that dual-contaminated river water was short of available electron donor, which resulted in low total nitrogen （TN） removal by denitrification. However, the denitrification rate was increased signifi- cantly by adding glucose or by making the organic matters of the river water more bioavailable through photocata- lysis. Photocatalysis for 15 min increased the Chemical Oxygen Demand （COD） of the river water from 53 to 84 mg. L-1 and led to a 4-fold increase in TN removal. The increase in TN removal gave the same effect as adding 92 mg.L 1 of glucose. During the photocatalysis experi- ments, the COD increased because photocatalysis trans- formed organic molecules from those that are resistant to dichromate oxidation in the COD test to those that can be oxidized by dichromate. This phenomenon was verified by testing photocatalysis of pyridine added to the river water. These findings point to the potential for N removal via denitrification after photocatalysis, and they also suggest that the rivers in China may be far more polluted than indicated by COD assays.

Detachment-Independent Cationic-Dipeptide Beacons:Reduced False-Negative Signal and Accelerated Fluorescent Lighting in Cell Imaging

Nanocarriers have been developed to deliver DNA probes into cells for imaging analysis and improving their nuclease resist-ance.However,we found obvious lowered sensitivity and even false-negative results in the traditional DNA detachment-dependent fluorescent lighting mechanism.Here,we developed a detachment-independent fluorescent lighting mechanism integrated with cationic dipeptide nanoparticles(CDNs).CDNs displayed little quenching effect on fluorophores labeled on probes and improved the nuclease resistance of probes.In contrast to the traditional beacon,the fluorescence lighting was significantly accelerated without the need of desorption of the recognition products from the nanosurface,avoiding false-negative results from non-specific conformational adsorption.This work will open up new thoughts to improve the sensing performance of DNA probes in cell imaging,such as speed and sensitivity.

An Activatable Nanoenzyme Reactor for Coenhanced Chemodynamic and Starving Therapy Against Tumor Hypoxia and Antioxidant Defense System

It is critical to improve the efficiency of cancer therapy with minimized side effects.Chemodynamic therapy(CDT)is a tumor therapeutic strategy designed to generate abundant reactive oxygen species(ROS)at tumor sites through a Fenton or Fenton-like reaction.Recently,this developing scheme has demonstrated an incredible promise for tumor therapy.The process involved could induce cell death without the input of external energy,and this could only occur via the conversion of hydrogen peroxide(H_(2)O_(2))to hydroxyl radicals(·OH).Although Fenton or Fenton-like reactions are being exploited for CDT,along with an application of oxidation reactions to supplement H_(2)O_(2),it has been proven that in cancer cells,the high levels of the existing antioxidants could suppress CDT via·OH depletion,and,unfortunately,tumor hypoxia also inhibits the oxidation reactions.Herein,the authors aimed to fabricate an activatable nanoenzyme reactor(NER)to solve this challenge.Fluorescent reporters(FRs)and bioenzyme glucose oxidase(GOX)were coassembled on nanozyme MnO_(2) nanosheets,which was enwrapped by the tumor-targeting material,hyaluronic acid(HA).NER was internalized explicitly by cancer cells through ligand/receptor recognitionmediated endocytosis,followed by intracellular hyaluronidase(HAase)-dependent activation.As a result,the oxygen level was improved,and the antioxidants were depleted,leading to the promotion of glucose consumption and an increase in·OH level.Thus,the NER exhibited multiple effects to induce coenhanced,chemodynamic and starving therapy against tumor hypoxia and antioxidant defense system to achieve a favorable targeted tumor therapeutic,via these rigorously highly effective,and targeted biochemical reactions both in an in vitro cultured cancer cells systemor in an in vivo mice tumor model.