Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 60
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Zhongguo Gu Shang ; 37(5): 445-50, 2024 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-38778526

RESUMO

OBJECTIVE: To investigate the clinical effect of orthopedic robot combined with Starr pelvic reduction frame in the treatment of Tile type C pelvic ring fracture. METHODS: From October 2019 to May 2021, 14 patients with type C pelvic ring fracture were treated with robotic combined with Starr pelvic reduction frame, including 9 males and 5 females. The age ranged from 33 to 69 years. All the 14 patients had fresh closed fractures without femur, tibia and fibula fracture. Surgery was completed from 4 to 7 d after hospital admission. During the operation, the X-ray carbon bed was used, the pelvic ring was reduced by Starr pelvis reduction frame, and pelvic ring fracture was treated by orthopedic robot. Operation time, bleeding volume, fluoroscopy times of single screw placement, fracture reduction quality, affected limb function and complications were observed. Radiological reduction was evaluated using Matta scoring standard, and clinical efficacy was evaluated by Majeed pelvic function scoring system at the final follow-up. RESULTS: All of 14 patients successfully completed the operation, the operation time was 84 to 141 min, the bleeding volume was 20 to 50 ml, and the fluoroscopy times of single screw insertion was 4 to 9 times. All of 14 patients were followed up for 12 to 24 months. The healing time was 3 to 7 months. No complications such as fracture of internal fixation, screw loosening, infection and nerve injury were found. According to the evaluation criteria of Matta imaging reduction, 9 cases were excellent, 4 cases were good, and 1 case was fair. At the final follow-up, Majeed pelvic function scoring system was used:10 cases were excellent, 4 cases were good. CONCLUSION: The treatment of type C pelvic ring fracture with robotic combined Starr pelvis reduction frame is simple, time-saving, less trauma, less complications and effective.


Assuntos
Fraturas Ósseas , Ossos Pélvicos , Procedimentos Cirúrgicos Robóticos , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Adulto , Ossos Pélvicos/lesões , Ossos Pélvicos/cirurgia , Idoso , Fraturas Ósseas/cirurgia , Procedimentos Cirúrgicos Robóticos/métodos , Fixação Interna de Fraturas/métodos
2.
J Gen Virol ; 105(4)2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38602389

RESUMO

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.


Assuntos
Hemípteros , Orthobunyavirus , Vírus de RNA , Animais , Feminino , Filogenia , Insetos , Vírus de RNA/genética
3.
Front Neurol ; 15: 1304524, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38585365

RESUMO

Background: Endovascular treatment of severe intracranial atherosclerotic stenosis (ICAS) using coronary drug-eluting stents (DESs) significantly reduces the risk of in-stent restenosis (ISR) and stroke recurrence. However, there are few reports regarding the treatment of ICAS with intracranial dedicated DES. Herein, we present our experience with the feasibility, safety, and medium-term follow-up outcomes of a novel intracranial DES, named NOVA stent, in patients with symptomatic severe ICAS (≥70%). Methods: From December 2021 to May 2022, patients with symptomatic severe ICAS who underwent implantation of the NOVA stent in our institution were retrospectively analyzed for procedural results, perioperative complications, imaging and clinical follow-up outcomes. Results: Twenty-four patients, 16 (66.7%) with anterior circulation lesions and 8 (33.3%) with posterior circulation lesions, were enrolled. All patients with intracranial ICA (n = 6), middle cerebral artery (n = 10), basilar artery (n = 3), intracranial vertebral artery (n = 3), and the vertebrobasilar junction (n = 2) stenosis were treated successfully using NOVA stents. The severity of stenosis ranged from 75 to 96% (mean 85.9%) before treatment and this was reduced to 0 to 20% (mean 8.6%) immediately after stent placement. Symptomatic distal embolism occurred in one case; however, there were no other perioperative complications. The mean follow-up duration was 12.2 ± 1.06 months. No symptomatic ischemic events occurred during follow-up. Follow-up cerebral angiography was performed in 22 of 24 patients (91.7%), and significant ISR occurred in one patient (4.2%). Conclusion: Our results demonstrate that implantation of the novel intracranial DES NOVA in severe ICAS is feasible, safe, and effective in selected cases, reducing the incidence of ISR, and showing excellent midterm clinical outcomes, providing a promising option for ICAS treatment.

4.
Sci Adv ; 10(17): eadk3852, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38657063

RESUMO

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.


Assuntos
Migração Animal , Genômica , Vento , Animais , Genômica/métodos , Hemípteros/genética , Genoma de Inseto , Genética Populacional
5.
Angew Chem Int Ed Engl ; 63(5): e202318441, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38098269

RESUMO

The construction of acyclic, non-adjacent 1,3-stereogenic centers, prevalent motifs in drugs and bioactive molecules, has been a long-standing synthetic challenge due to acyclic nucleophiles being distant from the chiral environment. In this study, we successfully synthesized highly valuable 1,2-bis(boronic) esters featuring acyclic and nonadjacent 1,3-stereocenters. Notably, this reaction selectively produces migratory coupling products rather than alternative deborylative allylation or direct allylation byproducts. This approach introduces a new activation mode for selective transformations of gem-diborylmethane in asymmetric catalysis. Additionally, we found that other gem-diborylalkanes, previously challenging due to steric hindrance, also successfully participated in this reaction. The incorporation of 1,2-bis(boryl)alkenes facilitated the diversification of the alkenyl and two boron moieties in our target compounds, thereby enabling access to a broad array of versatile molecules. DFT calculations were performed to elucidate the reaction mechanism and shed light on the factors responsible for the observed excellent enantioselectivity and diastereoselectivity. These were determined to arise from ligand-substrate steric repulsions in the syn-addition transition state.

6.
Nat Commun ; 14(1): 7264, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37945658

RESUMO

Non-retroviral endogenous viral elements (nrEVEs) are widely dispersed throughout the genomes of eukaryotes. Although nrEVEs are known to be involved in host antiviral immunity, it remains an open question whether they can be domesticated as functional proteins to serve cellular innovations in arthropods. In this study, we found that endogenous toti-like viral elements (ToEVEs) are ubiquitously integrated into the genomes of three planthopper species, with highly variable distributions and polymorphism levels in planthopper populations. Three ToEVEs display exon‒intron structures and active transcription, suggesting that they might have been domesticated by planthoppers. CRISPR/Cas9 experiments revealed that one ToEVE in Nilaparvata lugens, NlToEVE14, has been co-opted by its host and plays essential roles in planthopper development and fecundity. Large-scale analysis of ToEVEs in arthropod genomes indicated that the number of arthropod nrEVEs is currently underestimated and that they may contribute to the functional diversity of arthropod genes.


Assuntos
Artrópodes , Hemípteros , Animais , Artrópodes/genética , Hemípteros/genética , Retroviridae
7.
BMC Neurol ; 23(1): 376, 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37858051

RESUMO

BACKGROUND: Endovascular recanalization in patients with symptomatic nonacute intracranial large artery occlusion (ILAO) has been reported to be feasible, but technically challenging. This study aimed to determine the predictors of successful endovascular recanalization in patients with symptomatic nonacute ILAO. METHODS: The outcomes of endovascular recanalization attempts performed in 70 consecutive patients showing symptomatic nonacute ILAO with hemodynamic cerebral ischemia between January 2016 to December 2022 were reviewed. Potential variables, including clinical and radiological characteristics related to technical success, were collected. Univariate analysis and multivariate logistic regression were performed to identify predictors of successful recanalization for nonacute ILAO. RESULTS: Technically successful recanalization was achieved in 57 patients (81.4%). The periprocedural complication rate was 21.4% (15 of 70), and the overall 30-day morbidity and mortality rates were 7.1% (5 of 70) and 2.9% (2 of 70), respectively. Univariate analysis showed that successful recanalization was associated with occlusion duration, stump morphology, occlusion length, slow distal antegrade flow sign, and the presence of bridging collateral vessels. Multivariate analysis showed that occlusion duration ≤ 3 months (odds ratio [OR]: 22.529; 95% confidence interval [CI]: 1.636-310.141), tapered stump (OR: 7.498; 95% CI: 1.533-36.671), and occlusion length < 10 mm (OR: 7.049; 95% CI: 1.402-35.441) were independent predictive factors for technical success of recanalization. CONCLUSIONS: Occlusion duration ≤ 3 months, tapered stump, and occlusion length < 10 mm were independent positive predictors of technical success of endovascular recanalization for symptomatic nonacute ILAO. These findings may help predict the likelihood of successful recanalization in patients with symptomatic nonacute ILAO and also provide a reference for the selection of appropriate patients. Further prospective and multicenter studies are required to validate our findings.


Assuntos
Arteriopatias Oclusivas , Procedimentos Endovasculares , Humanos , Resultado do Tratamento , Artérias , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/cirurgia , Estudos Retrospectivos
8.
Commun Biol ; 6(1): 813, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-37542124

RESUMO

Insects have a limited host range due to genomic adaptation. Thysanoptera, commonly known as thrips, occupies distinct feeding habitats, but there is a lack of comparative genomic analyses and limited genomic resources available. In this study, the chromosome-level genome of Stenchaetothrips biformis, an oligophagous pest of rice, is assembled using multiple sequencing technologies, including PacBio, Illumina short-reads, and Hi-C technology. A 338.86 Mb genome is obtained, consisting of 1269 contigs with a contig N50 size of 381 kb and a scaffold N50 size of 18.21 Mb. Thereafter, 17,167 protein-coding genes and 36.25% repetitive elements are annotated. Comparative genomic analyses with two other polyphagous thrips, revealing contracted chemosensory-related and expanded stress response and detoxification gene families in S. biformis, potentially facilitating rice adaptation. In the polyphagous thrips species Frankliniella occidentalis and Thrips palmi, expanded gene families are enriched in metabolism of aromatic and anthocyanin-containing compounds, immunity against viruses, and detoxification enzymes. These expansion gene families play crucial roles not only in adapting to hosts but also in development of pesticide resistance, as evidenced by transcriptome results after insecticides treatment. This study provides a chromosome-level genome assembly and lays the foundation for further studies on thrips evolution and pest management.


Assuntos
Tisanópteros , Animais , Tisanópteros/genética , Adaptação ao Hospedeiro , Cromossomos , Genoma , Genômica/métodos
9.
Adv Mater ; 35(52): e2304736, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37494287

RESUMO

Despite remarkable improvement in the mobility of the organic field-effect transistors (OFETs) being achieved in past decades, the uniformity in electrical performance remains ambiguous, impeding their implantation in organic integrated circuits. The coefficient of variance (CV) in mobility of reported OFETs is typically larger than 8%, which is not adequate for building medium-to-large scale integrated circuits. In this work, it is shown that utilizing single-domain molecular monolayer crystals as the active channel can largely enhance the uniformity of OFETs. Benefiting from the sole molecular layer with long-range ordering, the OFETs exhibit uniformities in both channel transport and charge injection, thereby giving rise to a high average mobility of 11.64 cm2 V-1 s-1 and CV of only 2.57%. Statistical transmission length method evaluation is conducted, covering channel length from 3 to 21 µm, channel width from 90 to 170 µm, and a total OFET number of 370. The low contact resistance of 79.00 ± 7.00 Ω cm and high intrinsic mobility of 12.36 ± 0.45 cm2 V-1 s-1 are acquired with very high accuracy and reliability. As such, this work provides a practical way to enhance the uniformity of OFETs by a single-crystalline layer-controlled active channel toward their applications in integrated circuits.

10.
Angew Chem Int Ed Engl ; 62(32): e202307447, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37316685

RESUMO

Asymmetric cross-couplings based on 1,2-carbon migration from B-ate complexes have been developed efficiently to access valuable organoboronates. However, enantioselective reactions triggered by 1,2-boron shift have remained to be unaddressed synthetic challenge. Here, Ir-catalyzed asymmetric allylic alkylation enabled by 1,2-boron shift was developed. In this reaction, we disclosed that excellent enantioselectivities were achieved through an interesting dynamic kinetic resolution (DKR) process of allylic carbonates at the elevated temperature. Notably, the highly valuable (bis-boryl)alkenes have enabled an array of diversifications to access versatile molecules. Extensive experimental and computational studies were conducted to elucidate the reaction mechanism of DKR process and clarify the origin of excellent enantioselectivities.

11.
Mater Horiz ; 10(8): 3044-3050, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37212373

RESUMO

The use of microneedle (MN) systems has the potential to benefit a wide range of biomedical applications but is hindered by poorly controlled insertion. Herein, a novel MN penetration strategy is presented, which utilizes the recovery stress of near-infrared light-triggered shape memory polymers (SMPs) to drive MN insertion. This strategy enables force control over MN application with the precision of 15 mN through tunable light intensity. The pre-stretch strain of SMP can be further predetermined to provide a safety margin on penetration depth. Using this strategy, we demonstrate that MN can precisely insert into the stromal layer of the rabbit cornea. Additionally, the MN unit array allows programmable insertion for multistage and patterned payload delivery. This proof-of-concept strategy promises remotely, precisely, and spatiotemporally controlled MN insertion, which may inspire the further development of MN-related applications.

12.
PLoS Pathog ; 19(3): e1011266, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36928081

RESUMO

The Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway is an evolutionarily conserved signaling pathway that can regulate various biological processes. However, the role of JAK-STAT pathway in the persistent viral infection in insect vectors has rarely been investigated. Here, using a system that comprised two different plant viruses, Rice stripe virus (RSV) and Rice black-streaked dwarf virus (RBSDV), as well as their insect vector small brown planthopper, we elucidated the regulatory mechanism of JAK-STAT pathway in persistent viral infection. Both RSV and RBSDV infection activated the JAK-STAT pathway and promoted the accumulation of suppressor of cytokine signaling 5 (SOCS5), an E3 ubiquitin ligase regulated by the transcription factor STAT5B. Interestingly, the virus-induced SOCS5 directly interacted with the anti-apoptotic B-cell lymphoma-2 (BCL2) to accelerate the BCL2 degradation through the 26S proteasome pathway. As a result, the activation of apoptosis facilitated persistent viral infection in their vector. Furthermore, STAT5B activation promoted virus amplification, whereas STAT5B suppression inhibited apoptosis and reduced virus accumulation. In summary, our results reveal that virus-induced JAK-STAT pathway regulates apoptosis to promote viral infection, and uncover a new regulatory mechanism of the JAK-STAT pathway in the persistent plant virus transmission by arthropod vectors.


Assuntos
Tenuivirus , Viroses , Animais , Janus Quinases/metabolismo , Transdução de Sinais , Fatores de Transcrição STAT/metabolismo , Tenuivirus/metabolismo , Insetos Vetores , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
13.
Nat Commun ; 14(1): 737, 2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36759625

RESUMO

Salivary elicitors secreted by herbivorous insects can be perceived by host plants to trigger plant immunity. However, how insects secrete other salivary components to subsequently attenuate the elicitor-induced plant immunity remains poorly understood. Here, we study the small brown planthopper, Laodelphax striatellus salivary sheath protein LsSP1. Using Y2H, BiFC and LUC assays, we show that LsSP1 is secreted into host plants and binds to salivary sheath via mucin-like protein (LsMLP). Rice plants pre-infested with dsLsSP1-treated L. striatellus are less attractive to L. striatellus nymphs than those pre-infected with dsGFP-treated controls. Transgenic rice plants with LsSP1 overexpression rescue the insect feeding defects caused by a deficiency of LsSP1 secretion, consistent with the potential role of LsSP1 in manipulating plant defenses. Our results illustrate the importance of salivary sheath proteins in mediating the interactions between plants and herbivorous insects.


Assuntos
Hemípteros , Oryza , Animais , Oryza/genética , Hemípteros/genética , Herbivoria , Plantas Geneticamente Modificadas , Ninfa
14.
J Org Chem ; 88(1): 261-271, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36520655

RESUMO

We report the first general and practical method for the addition of aryl halides and alkynes to norbornenes with palladium catalysis. Norbornenes have been used as the unsaturated acceptors of aryl and alkynyl groups to construct saturated bridged C-C bonds. The combination of Pd(OAc)2/PCy3HBF4 has been identified as the optimal system promoting difunctionalization of norbornenes via the C-X/C-H bond cleavage and highly selective C(sp3)-C(sp2)/C(sp3)-C(sp) bond formation. Broad substrate scope and excellent functional group tolerance have been achieved to show the high efficiency of this approach. Mechanism studies based on experiments and DFT have been performed to gain insights into the catalytic mechanism.

16.
Genome Biol Evol ; 14(11)2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36317697

RESUMO

In insects, sex chromosome differentiation often results in unequal gene dosages between sexes. Dosage compensation mechanisms evolve to balance gene expression, but the degree and mechanism of regulation often vary by insect species. In hemipteran species, the small brown planthopper (SBPH), Laodelphax striatellus, is an injurious crop pest, with a sex chromosome type XX in females and XO in males. This species offers the opportunity to study dosage compensation and sex-biased gene expression. In this study, we generated a chromosome-level genome of SBPH using Oxford Nanopore Technologies and high-throughput chromatin conformation capture (Hi-C) technology. We also sequenced RNA-seq data from 16 tissue samples to annotate the genome and analyze gene dosage compensation. We finally obtained a 510.2 megabases (Mb) genome with 99.12% of the scaffolds anchored on 15 chromosomes (14 autosomes and 1 X chromosome) and annotated 16,160 protein-coding genes based on full-length cDNA sequencing data. Furthermore, we found complete dosage compensation in all L. striatellus somatic tissues, but lack of dosage compensation in gonad tissue testis. We also found that female-biased genes were significantly enriched on the X chromosome in all tissues, whereas male-biased genes in gonad tissues were enriched on autosomes. This study not only provides a high-quality genome assembly but also lays a foundation for a better understanding of the sexual regulatory network in hemipteran insects.


Assuntos
Mecanismo Genético de Compensação de Dose , Hemípteros , Animais , Feminino , Masculino , Cromossomo X/genética , Cromossomos Sexuais/genética , Hemípteros/genética , Expressão Gênica
17.
J Org Chem ; 87(16): 11204-11217, 2022 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-35930660

RESUMO

The α-methylene-γ-lactam offers promise as a complementary warhead for the development of targeted covalent inhibitors. However, an understanding of the factors governing its electrophilic reactivity is needed to promote the development of lead compounds utilizing this motif. Herein we synthesize a series of N-aryl-substituted α-methylene-γ-lactams installed within the framework of a bioactive guaianolide analog. To determine the effects of the guaianolide structure on the electrophilic reactivity, these compounds were reacted with glutathione under biomimetic conditions, and the rate constants were measured. A linear free-energy relationship was observed with the Hammett parameter of the N-aryl group within the cis- or trans-annulated isomeric series of compounds. However, the trans-annulated compounds exhibited a ca. 10-fold increase in reactivity relative to both the cis-annulated compounds and the corresponding N-arylated 3-methylene-2-pyrrolidinones. Density functional theory calculations revealed that the reactivity of the trans-annulated stereoisomers is promoted by the partial release of the ring strain of the fused seven-membered ring in the thio-Michael addition transition state.


Assuntos
Lactamas , Compostos de Sulfidrila , Glutationa , Lactamas/química , Estrutura Molecular , Estereoisomerismo , Compostos de Sulfidrila/química
19.
Front Immunol ; 12: 689065, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34733269

RESUMO

Coronavirus disease 2019 (COVID-19) is an acute respiratory infectious disease caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The US FDA has approved several therapeutics and vaccines worldwide through the emergency use authorization in response to the rapid spread of COVID-19. Nevertheless, the efficacies of these treatments are being challenged by viral escape mutations. There is an urgent need to develop effective treatments protecting against SARS-CoV-2 infection and to establish a stable effect-screening model to test potential drugs. Polyclonal antibodies (pAbs) have an intrinsic advantage in such developments because they can target rapidly mutating viral strains as a result of the complexity of their binding epitopes. In this study, we generated anti-receptor-binding domain (anti-RBD) pAbs from rabbit serum and tested their safety and efficacy in response to SARS-CoV-2 infection both in vivo and ex vivo. Primary human bronchial epithelial two-dimensional (2-D) organoids were cultured and differentiated to a mature morphology and subsequently employed for SARS-CoV-2 infection and drug screening. The pAbs protected the airway organoids from viral infection and tissue damage. Potential side effects were tested in mouse models for both inhalation and vein injection. The pAbs displayed effective viral neutralization effects without significant side effects. Thus, the use of animal immune serum-derived pAbs might be a potential therapy for protection against SARS-CoV-2 infection, with the strategy developed to produce these pAbs providing new insight into the treatment of respiratory tract infections, especially for infections with viruses undergoing rapid mutation.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Animais , Anticorpos Neutralizantes/administração & dosagem , Anticorpos Antivirais/administração & dosagem , Sítios de Ligação , Brônquios/citologia , COVID-19/genética , COVID-19/terapia , Células Epiteliais , Perfilação da Expressão Gênica , Humanos , Imunização Passiva , Camundongos , Mutação , Testes de Neutralização , Organoides , Coelhos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Soroterapia para COVID-19
20.
Sci Adv ; 7(48): eabf9237, 2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34826246

RESUMO

The mechanism of sex determination remains poorly understood in hemimetabolous insects. Here, in the brown planthopper (BPH), Nilaparvata lugens, a hemipteran rice pest, we identified a feminizing switch or a female determiner (Nlfmd) that encodes a serine/arginine-rich protein. Knockdown of Nlfmd in female nymphs resulted in masculinization of both the somatic morphology and doublesex splicing. The female-specific isoform of Nlfmd, Nlfmd-F, is maternally deposited and zygotically transcribed. Depletion of Nlfmd by maternal RNAi or CRISPR-Cas9 resulted in female-specific embryonic lethality. Knockdown of an hnRNP40 family gene named female determiner 2 (Nlfmd2) also conferred masculinization. In vitro experiments showed that an Nlfmd2 isoform, NlFMD2340, bound the RAAGAA repeat motif in the Nldsx pre-mRNA and formed a protein complex with NlFMD-F to modulate Nldsx splicing, suggesting that NlFMD2 may function as an RNA binding partner of the feminizing switch NlFMD. Our results provide novel insights into the diverse mechanisms of insect sex determination.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA