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1.
Cell ; 187(16): 4261-4271.e17, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-38964329

RESUMO

The entry of coronaviruses is initiated by spike recognition of host cellular receptors, involving proteinaceous and/or glycan receptors. Recently, TMPRSS2 was identified as the proteinaceous receptor for HCoV-HKU1 alongside sialoglycan as a glycan receptor. However, the underlying mechanisms for viral entry remain unknown. Here, we investigated the HCoV-HKU1C spike in the inactive, glycan-activated, and functionally anchored states, revealing that sialoglycan binding induces a conformational change of the NTD and promotes the neighboring RBD of the spike to open for TMPRSS2 recognition, exhibiting a synergistic mechanism for the entry of HCoV-HKU1. The RBD of HCoV-HKU1 features an insertion subdomain that recognizes TMPRSS2 through three previously undiscovered interfaces. Furthermore, structural investigation of HCoV-HKU1A in combination with mutagenesis and binding assays confirms a conserved receptor recognition pattern adopted by HCoV-HKU1. These studies advance our understanding of the complex viral-host interactions during entry, laying the groundwork for developing new therapeutics against coronavirus-associated diseases.


Assuntos
Serina Endopeptidases , Glicoproteína da Espícula de Coronavírus , Internalização do Vírus , Humanos , Serina Endopeptidases/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Polissacarídeos/metabolismo , Polissacarídeos/química , Células HEK293 , Ligação Proteica , Receptores Virais/metabolismo , Receptores Virais/química , Coronavirus/metabolismo , Modelos Moleculares
2.
Plant Cell ; 36(10): 4388-4403, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-38917216

RESUMO

Plants generally enhance their root growth in the form of greater biomass and/or root length to boost nutrient uptake in response to short-term low nitrogen (LN). However, the underlying mechanisms of short-term LN-mediated root growth remain largely elusive. Our genome-wide association study, haplotype analysis, and phenotyping of transgenic plants showed that the crucial nitrate signaling component NIN-LIKE PROTEIN3.2 (ZmNLP3.2), a positive regulator of root biomass, is associated with natural variations in root biomass of maize (Zea mays L.) seedlings under LN. The monocot-specific gene AUXIN/INDOLE-3-ACETIC ACID14 (ZmAux/IAA14) exhibited opposite expression patterns to ZmNLP3.2 in ZmNLP3.2 knockout and overexpression lines, suggesting that ZmNLP3.2 hampers ZmAux/IAA14 transcription. Importantly, ZmAux/IAA14 knockout seedlings showed a greater root dry weight (RDW), whereas ZmAux/IAA14 overexpression reduced RDW under LN compared with wild-type plants, indicating that ZmAux/IAA14 negatively regulates the RDW of LN-grown seedlings. Moreover, in vitro and vivo assays indicated that AUXIN RESPONSE FACTOR19 (ZmARF19) binds to and transcriptionally activates ZmAux/IAA14, which was weakened by the ZmNLP3.2-ZmARF19 interaction. The zmnlp3.2 ZmAux/IAA14-OE seedlings exhibited further reduced RDW compared with ZmAux/IAA14 overexpression lines when subjected to LN treatment, corroborating the ZmNLP3.2-ZmAux/IAA14 interaction. Thus, our study reveals a ZmNLP3.2-ZmARF19-ZmAux/IAA14 module regulating root biomass in response to nitrogen limitation in maize.


Assuntos
Biomassa , Regulação da Expressão Gênica de Plantas , Nitrogênio , Proteínas de Plantas , Raízes de Plantas , Plântula , Zea mays , Zea mays/genética , Zea mays/metabolismo , Zea mays/crescimento & desenvolvimento , Nitrogênio/metabolismo , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Ácidos Indolacéticos/metabolismo , Estudo de Associação Genômica Ampla
3.
PLoS Pathog ; 20(3): e1012086, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38484013

RESUMO

Papain-like cysteine proteases (PLCPs) play pivotal roles in plant defense against pathogen invasions. While pathogens can secrete effectors to target and inhibit PLCP activities, the roles of PLCPs in plant-virus interactions and the mechanisms through which viruses neutralize PLCP activities remain largely uncharted. Here, we demonstrate that the expression and activity of a maize PLCP CCP1 (Corn Cysteine Protease), is upregulated following sugarcane mosaic virus (SCMV) infection. Transient silencing of CCP1 led to a reduction in PLCP activities, thereby promoting SCMV infection in maize. Furthermore, the knockdown of CCP1 resulted in diminished salicylic acid (SA) levels and suppressed expression of SA-responsive pathogenesis-related genes. This suggests that CCP1 plays a role in modulating the SA signaling pathway. Interestingly, NIa-Pro, the primary protease of SCMV, was found to interact with CCP1, subsequently inhibiting its protease activity. A specific motif within NIa-Pro termed the inhibitor motif was identified as essential for its interaction with CCP1 and the suppression of its activity. We have also discovered that the key amino acids responsible for the interaction between NIa-Pro and CCP1 are crucial for the virulence of SCMV. In conclusion, our findings offer compelling evidence that SCMV undermines maize defense mechanisms through the interaction of NIa-Pro with CCP1. Together, these findings shed a new light on the mechanism(s) controlling the arms races between virus and plant.


Assuntos
Cisteína Proteases , Vírus do Mosaico , Potyvirus , Zea mays/genética , Cisteína Proteases/genética , Ácido Salicílico/metabolismo , Vírus do Mosaico/metabolismo , Doenças das Plantas
4.
PLoS Pathog ; 18(12): e1011036, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36480554

RESUMO

Serine/arginine-rich (SR) proteins are well known as splicing factors in humans, model animals and plants. However, they are largely unknown in regulating pre-mRNA splicing of filamentous fungi. Here we report that the SR protein MoSrp1 enhances and suppresses alternative splicing in a model fungal plant pathogen Magnaporthe oryzae. Deletion of MoSRP1 caused multiple defects, including reduced virulence and thousands of aberrant alternative splicing events in mycelia, most of which were suppressed or enhanced intron splicing. A GUAG consensus bound by MoSrp1 was identified in more than 94% of the intron or/and proximate exons having the aberrant splicing. The dual functions of regulating alternative splicing of MoSrp1 were exemplified in enhancing and suppressing the consensus-mediated efficient splicing of the introns in MoATF1 and MoMTP1, respectively, which both were important for mycelial growth, conidiation, and virulence. Interestingly, MoSrp1 had a conserved sumoylation site that was essential to nuclear localization and enhancing GUAG binding. Further, we showed that MoSrp1 interacted with a splicing factor and two components of the exon-joining complex via its N-terminal RNA recognition domain, which was required to regulate mycelial growth, development and virulence. In contrast, the C-terminus was important only for virulence and stress responses but not for mycelial growth and development. In addition, only orthologues from Pezizomycotina species could completely rescue defects of the deletion mutants. This study reveals that the fungal conserved SR protein Srp1 regulates alternative splicing in a unique manner.


Assuntos
Processamento Alternativo , Ascomicetos , Proteínas Fúngicas , Oryza , Ascomicetos/genética , Oryza/microbiologia , Fatores de Processamento de Serina-Arginina/genética , Proteínas Fúngicas/genética
5.
Invest New Drugs ; 2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39154300

RESUMO

Obstacles facing chemotherapeutic drugs for cancers led scientists to load Gemcitabine (GEM) into nanocarriers like liposomes, known for their nontoxicity profile and targeting capacity. The liposomal nanostructures containing GEM were coated with Fucoidan (FU) due to its anti-tumor properties by targeting cancer cells. Thus four different cationic liposomes formulations were prepared by thin-film hydration method in optimal conditions: DOTAP (formulation A); DPPC/DOTAP (4:1 molar ratio, formulation B), DPPC/DMPC/DOTAP (4:1:1 molar ratio, formulation C) and DPPC/DMPC/DOTAP/DSPE-mPEG2000 (4:1:1:0.1 molar ratio, formulation D). They were studied to identify lipid-compositions offering effective GEM-entrapment and successful coating of FU on the liposome surface. Additional qualitative characteristics, such as particle size, polydispersity index, zeta potential, stability and in vitro drug release were then evaluated. Formulation C gave the best GEM-entrapment efficiency (EE) but formed aggregates when coated with FU, giving non-homogenous large size particles then not suitable for effective delivery. It was the same situation with formulation A and B. Only the formulation D showed a good GEM-EE (> 80%) and affinity by successful coating FU from three different algae species. The PEGylated formulation D coated of FU, with regard to storage stability and drug release studies, revealed to be a promising approach on design of optimal drug delivery system.

6.
J Exp Bot ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39271137

RESUMO

Angelica sinensis is a traditional Chinese herbal medicine with significant economic and medicinal value. However, early bolting and flowering can occur during the second year of the vegetative growth period, rendering the roots unviable for medicinal use and resulting in substantial economic losses. Consequently, the growing interest in studying the molecular mechanisms underlying early bolting or increased root lignification in A. sinensis. Here, we conducted whole-genome bisulfite sequencing and observed an increase in whole-genome DNA methylation levels on chromosomes after bolting in A. sinensis. Comparative analysis revealed methylation patterns in the upstream, gene body, and downstream regions in the context of CG, CHG, and CHH, suggesting a possible association between CHH-type methylation of promoters and phenylpropanoid biosynthesis. Furthermore, joint analysis of transcriptomic and methylomics data revealed a positive correlation between DNA methylation and gene expression. We identified the hyperDMR gene in the CHH background within the promoter region; this gene is also a key gene (AsCOMT1), exhibiting dual catalytic activity and facilitating the synthesis of both ferulic acid and lignin. Enzyme kinetic analysis demonstrated that AsCOMT1 preferentially catalyzes the synthesis of lignin monomer precursors. These findings highlight the important regulatory role of DNA methylation in bolting and the synthesis of secondary metabolites in A. sinensis, providing valuable insights into the underlying molecular mechanisms. Therefore, as DNA methylation plays an important regulatory role in A. sinensis bolting and secondary metabolite synthesis, it has potential significance in the analysis of the underlying molecular mechanism.

7.
Physiol Plant ; 176(5): e14500, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39221482

RESUMO

Angelica sinensis, a traditional Chinese medicinal plant, has been primarily reported due to its nutritional value. Pigmentation in this plant is an important appearance trait that directly affects its commercial value. To understand the mechanism controlling purpleness in A. sinensis, hormonal and transcriptomic analyses were performed in three different tissues (leave, root and stem), using two cultivars with contrasting colors. The two-dimensional data set provides dynamic hormonal and gene expression networks underpinning purpleness in A. sinensis. We found abscisic acid as a crucial hormone modulating anthocyanin biosynthesis in A. sinensis. We further identified and validated 7 key genes involved in the anthocyanin biosynthesis pathway and found a specific module containing ANS as a hub gene in WGCNA. Overexpression of a candidate pigment regulatory gene, AsANS (AS08G02092), in transgenic calli of A. sinensis resulted in increased anthocyanin production and caused purpleness. Together, these analyses provide an important understanding of the molecular networks underlying A. sinensis anthocyanin production and its correlation with plant hormones, which can provide an important source for breeding.


Assuntos
Angelica sinensis , Antocianinas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas , Proteínas de Plantas , Angelica sinensis/genética , Angelica sinensis/metabolismo , Antocianinas/biossíntese , Antocianinas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transcriptoma/genética , Pigmentação/genética , Ácido Abscísico/metabolismo , Pigmentos Biológicos/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo
8.
J Nanobiotechnology ; 22(1): 200, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654299

RESUMO

The glymphatic system plays an important role in the transportation of cerebrospinal fluid (CSF) and the clearance of metabolite waste in brain. However, current imaging modalities for studying the glymphatic system are limited. Herein, we apply NIR-II nanoprobes with non-invasive and high-contrast advantages to comprehensively explore the function of glymphatic system in mice under anesthesia and cerebral ischemia-reperfusion injury conditions. Our results show that the supplement drug dexmedetomidine (Dex) enhances CSF influx in the brain, decreases its outflow to mandibular lymph nodes, and leads to significant differences in CSF accumulation pattern in the spine compared to isoflurane (ISO) alone, while both ISO and Dex do not affect the clearance of tracer-filled CSF into blood circulation. Notably, we confirm the compromised glymphatic function after cerebral ischemia-reperfusion injury, leading to impaired glymphatic influx and reduced glymphatic efflux. This technique has great potential to elucidate the underlying mechanisms between the glymphatic system and central nervous system diseases.


Assuntos
Sistema Glinfático , Traumatismo por Reperfusão , Animais , Sistema Glinfático/metabolismo , Camundongos , Traumatismo por Reperfusão/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Encéfalo/metabolismo , Dexmedetomidina/farmacologia , Acidente Vascular Cerebral , Anestesia , Isoflurano/farmacologia , Nanopartículas/química , Líquido Cefalorraquidiano/metabolismo , Líquido Cefalorraquidiano/química
9.
Int J Mol Sci ; 25(13)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39000250

RESUMO

Beef is a major global source of protein, playing an essential role in the human diet. The worldwide production and consumption of beef continue to rise, reflecting a significant trend. However, despite the critical importance of beef cattle resources in agriculture, the diversity of cattle breeds faces severe challenges, with many breeds at risk of extinction. The initiation of the Beef Cattle Genome Project is crucial. By constructing a high-precision functional annotation map of their genome, it becomes possible to analyze the genetic mechanisms underlying important traits in beef cattle, laying a solid foundation for breeding more efficient and productive cattle breeds. This review details advances in genome sequencing and assembly technologies, iterative upgrades of the beef cattle reference genome, and its application in pan-genome research. Additionally, it summarizes relevant studies on the discovery of functional genes associated with key traits in beef cattle, such as growth, meat quality, reproduction, polled traits, disease resistance, and environmental adaptability. Finally, the review explores the potential of telomere-to-telomere (T2T) genome assembly, structural variations (SVs), and multi-omics techniques in future beef cattle genetic breeding. These advancements collectively offer promising avenues for enhancing beef cattle breeding and improving genetic traits.


Assuntos
Genoma , Animais , Bovinos/genética , Genômica/métodos , Cruzamento/métodos , Sequenciamento Completo do Genoma/métodos , Carne Vermelha , Locos de Características Quantitativas
10.
Int J Mol Sci ; 25(17)2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39273219

RESUMO

The economic significance of ruminants in agriculture underscores the need for advanced research methodologies to enhance their traits. This review aims to elucidate the transformative role of pan-omics technologies in ruminant research, focusing on their application in uncovering the genetic mechanisms underlying complex traits such as growth, reproduction, production performance, and rumen function. Pan-omics analysis not only helps in identifying key genes and their regulatory networks associated with important economic traits but also reveals the impact of environmental factors on trait expression. By integrating genomics, epigenomics, transcriptomics, metabolomics, and microbiomics, pan-omics enables a comprehensive analysis of the interplay between genetics and environmental factors, offering a holistic understanding of trait expression. We explore specific examples of economic traits where these technologies have been pivotal, highlighting key genes and regulatory networks identified through pan-omics approaches. Additionally, we trace the historical evolution of each omics field, detailing their progression from foundational discoveries to high-throughput platforms. This review provides a critical synthesis of recent advancements, offering new insights and practical recommendations for the application of pan-omics in the ruminant industry. The broader implications for modern animal husbandry are discussed, emphasizing the potential for these technologies to drive sustainable improvements in ruminant production systems.


Assuntos
Genômica , Metabolômica , Ruminantes , Animais , Ruminantes/genética , Genômica/métodos , Metabolômica/métodos , Epigenômica/métodos , Criação de Animais Domésticos/métodos , Criação de Animais Domésticos/economia , Multiômica
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