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1.
Nature ; 630(8016): 484-492, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38811729

RESUMO

The CRISPR system is an adaptive immune system found in prokaryotes that defends host cells against the invasion of foreign DNA1. As part of the ongoing struggle between phages and the bacterial immune system, the CRISPR system has evolved into various types, each with distinct functionalities2. Type II Cas9 is the most extensively studied of these systems and has diverse subtypes. It remains uncertain whether members of this family can evolve additional mechanisms to counter viral invasions3,4. Here we identify 2,062 complete Cas9 loci, predict the structures of their associated proteins and reveal three structural growth trajectories for type II-C Cas9. We found that novel associated genes (NAGs) tended to be present within the loci of larger II-C Cas9s. Further investigation revealed that CbCas9 from Chryseobacterium species contains a novel ß-REC2 domain, and forms a heterotetrameric complex with an NAG-encoded CRISPR-Cas-system-promoting (pro-CRISPR) protein of II-C Cas9 (PcrIIC1). The CbCas9-PcrIIC1 complex exhibits enhanced DNA binding and cleavage activity, broader compatibility for protospacer adjacent motif sequences, increased tolerance for mismatches and improved anti-phage immunity, compared with stand-alone CbCas9. Overall, our work sheds light on the diversity and 'growth evolutionary' trajectories of II-C Cas9 proteins at the structural level, and identifies many NAGs-such as PcrIIC1, which serves as a pro-CRISPR factor to enhance CRISPR-mediated immunity.


Assuntos
Bactérias , Bacteriófagos , Proteína 9 Associada à CRISPR , Sistemas CRISPR-Cas , Bactérias/virologia , Bactérias/genética , Bactérias/imunologia , Bacteriófagos/genética , Bacteriófagos/imunologia , Chryseobacterium/genética , Chryseobacterium/imunologia , Chryseobacterium/virologia , Proteína 9 Associada à CRISPR/química , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Sistemas CRISPR-Cas/imunologia , Clivagem do DNA , Loci Gênicos/genética , Modelos Moleculares , Domínios Proteicos
2.
Nature ; 609(7929): 964-968, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36171375

RESUMO

Mandibular teeth and dentitions are features of jawed vertebrates that were first acquired by the Palaeozoic ancestors1-3 of living chondrichthyans and osteichthyans. The fossil record currently points to the latter part of the Silurian period4-7 (around 425 million years ago) as a minimum date for the appearance of gnathostome teeth and to the evolution of growth and replacement mechanisms of mandibular dentitions in the subsequent Devonian period2,8-10. Here we provide, to our knowledge, the earliest direct evidence for jawed vertebrates by describing Qianodus duplicis, a new genus and species of an early Silurian gnathostome based on isolated tooth whorls from Guizhou province, China. The whorls possess non-shedding teeth arranged in a pair of rows that demonstrate a number of features found in modern gnathostome groups. These include lingual addition of teeth in offset rows and maintenance of this patterning throughout whorl development. Our data extend the record of toothed gnathostomes by 14 million years from the late Silurian into the early Silurian (around 439 million years ago) and are important for documenting the initial diversification of vertebrates. Our analyses add to mounting fossil evidence that supports an earlier emergence of jawed vertebrates as part of the Great Ordovician Biodiversification Event (approximately 485-445 million years ago).


Assuntos
Fósseis , Dente , Vertebrados , Animais , China , Peixes/anatomia & histologia , História Antiga , Filogenia , Dente/anatomia & histologia , Vertebrados/anatomia & histologia , Vertebrados/classificação
3.
Nature ; 609(7929): 969-974, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36171377

RESUMO

Modern representatives of chondrichthyans (cartilaginous fishes) and osteichthyans (bony fishes and tetrapods) have contrasting skeletal anatomies and developmental trajectories1-4 that underscore the distant evolutionary split5-7 of the two clades. Recent work on upper Silurian and Devonian jawed vertebrates7-10 has revealed similar skeletal conditions that blur the conventional distinctions between osteichthyans, chondrichthyans and their jawed gnathostome ancestors. Here we describe the remains (dermal plates, scales and fin spines) of a chondrichthyan, Fanjingshania renovata gen. et sp. nov., from the lower Silurian of China that pre-date the earliest articulated fossils of jawed vertebrates10-12. Fanjingshania possesses dermal shoulder girdle plates and a complement of fin spines that have a striking anatomical similarity to those recorded in a subset of stem chondrichthyans5,7,13 (climatiid 'acanthodians'14). Uniquely among chondrichthyans, however, it demonstrates osteichthyan-like resorptive shedding of scale odontodes (dermal teeth) and an absence of odontogenic tissues in its spines. Our results identify independent acquisition of these conditions in the chondrichthyan stem group, adding Fanjingshania to an increasing number of taxa7,15 nested within conventionally defined acanthodians16. The discovery of Fanjingshania provides the strongest support yet for a proposed7 early Silurian radiation of jawed vertebrates before their widespread appearance5 in the fossil record in the Lower Devonian series.


Assuntos
Peixes , Fósseis , Filogenia , Animais , China , Peixes/anatomia & histologia , Peixes/classificação , Arcada Osseodentária/anatomia & histologia , Dente
4.
Nature ; 609(7929): 954-958, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36171378

RESUMO

Molecular studies suggest that the origin of jawed vertebrates was no later than the Late Ordovician period (around 450 million years ago (Ma))1,2. Together with disarticulated micro-remains of putative chondrichthyans from the Ordovician and early Silurian period3-8, these analyses suggest an evolutionary proliferation of jawed vertebrates before, and immediately after, the end-Ordovician mass extinction. However, until now, the earliest complete fossils of jawed fishes for which a detailed reconstruction of their morphology was possible came from late Silurian assemblages (about 425 Ma)9-13. The dearth of articulated, whole-body fossils from before the late Silurian has long rendered the earliest history of jawed vertebrates obscure. Here we report a newly discovered Konservat-Lagerstätte, which is marked by the presence of diverse, well-preserved jawed fishes with complete bodies, from the early Silurian (Telychian age, around 436 Ma) of Chongqing, South China. The dominant species, a 'placoderm' or jawed stem gnathostome, which we name Xiushanosteus mirabilis gen. et sp. nov., combines characters from major placoderm subgroups14-17 and foreshadows the transformation of the skull roof pattern from the placoderm to the osteichthyan condition10. The chondrichthyan Shenacanthus vermiformis gen. et sp. nov. exhibits extensive thoracic armour plates that were previously unknown in this lineage, and include a large median dorsal plate as in placoderms14-16, combined with a conventional chondrichthyan bauplan18,19. Together, these species reveal a previously unseen diversification of jawed vertebrates in the early Silurian, and provide detailed insights into the whole-body morphology of the jawed vertebrates of this period.


Assuntos
Fósseis , Arcada Osseodentária , Vertebrados , Animais , China , Peixes/anatomia & histologia , Peixes/classificação , Arcada Osseodentária/anatomia & histologia , Filogenia , Crânio/anatomia & histologia , Vertebrados/anatomia & histologia , Vertebrados/classificação
5.
Development ; 150(24)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38031990

RESUMO

Balanced control of stem cell proliferation and differentiation underlines tissue homeostasis. Disruption of tissue homeostasis often results in many diseases. However, how endogenous factors influence the proliferation and differentiation of intestinal stem cells (ISCs) under physiological and pathological conditions remains poorly understood. Here, we find that the evolutionarily conserved endoplasmic reticulum membrane protein complex (EMC) negatively regulates ISC proliferation and intestinal homeostasis. Compromising EMC function in progenitors leads to excessive ISC proliferation and intestinal homeostasis disruption. Mechanistically, the EMC associates with and stabilizes Hippo (Hpo) protein, the key component of the Hpo signaling pathway. In the absence of EMC, Yorkie (Yki) is activated to promote ISC proliferation due to Hpo destruction. The EMC-Hpo-Yki axis also functions in enterocytes to maintain intestinal homeostasis. Importantly, the levels of the EMC are dramatically diminished in tunicamycin-treated animals, leading to Hpo destruction, thereby resulting in intestinal homeostasis disruption due to Yki activation. Thus, our study uncovers the molecular mechanism underlying the action of the EMC in intestinal homeostasis maintenance under physiological and pathological conditions and provides new insight into the pathogenesis of tunicamycin-induced tumorigenesis.


Assuntos
Proteínas de Drosophila , Proteínas Serina-Treonina Quinases , Animais , Proteínas Serina-Treonina Quinases/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Transdução de Sinais/fisiologia , Proteínas de Drosophila/metabolismo , Tunicamicina/metabolismo , Transativadores/metabolismo , Proliferação de Células , Proteínas Nucleares/metabolismo , Homeostase , Drosophila melanogaster/metabolismo
6.
Nucleic Acids Res ; 52(D1): D963-D971, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37953384

RESUMO

Polygenic score (PGS) is an important tool for the genetic prediction of complex traits. However, there are currently no resources providing comprehensive PGSs computed from published summary statistics, and it is difficult to implement and run different PGS methods due to the complexity of their pipelines and parameter settings. To address these issues, we introduce a new resource called PGS-Depot containing the most comprehensive set of publicly available disease-related GWAS summary statistics. PGS-Depot includes 5585 high quality summary statistics (1933 quantitative and 3652 binary trait statistics) curated from 1564 traits in European and East Asian populations. A standardized best-practice pipeline is used to implement 11 summary statistics-based PGS methods, each with different model assumptions and estimation procedures. The prediction performance of each method can be compared for both in- and cross-ancestry populations, and users can also submit their own summary statistics to obtain custom PGS with the available methods. Other features include searching for PGSs by trait name, publication, cohort information, population, or the MeSH ontology tree and searching for trait descriptions with the experimental factor ontology (EFO). All scores, SNP effect sizes and summary statistics can be downloaded via FTP. PGS-Depot is freely available at http://www.pgsdepot.net.


Assuntos
Bioestatística , Herança Multifatorial , Estudo de Associação Genômica Ampla , Herança Multifatorial/genética , Fenótipo , Polimorfismo de Nucleotídeo Único , Bioestatística/métodos
7.
Traffic ; 24(12): 552-563, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37642208

RESUMO

Epithelial polarity is critical for proper functions of epithelial tissues, tumorigenesis, and metastasis. The evolutionarily conserved transmembrane protein Crumbs (Crb) is a key regulator of epithelial polarity. Both Crb protein and its transcripts are apically localized in epithelial cells. However, it remains not fully understood how they are targeted to the apical domain. Here, using Drosophila ovarian follicular epithelia as a model, we show that epithelial polarity is lost and Crb protein is absent in the apical domain in follicular cells (FCs) in the absence of Diamond (Dind). Interestingly, Dind is found to associate with different components of the dynactin-dynein complex through co-IP-MS analysis. Dind stabilizes dynactin and depletion of dynactin results in almost identical defects as those observed in dind-defective FCs. Finally, both Dind and dynactin are also required for the apical localization of crb transcripts in FCs. Thus our data illustrate that Dind functions through dynactin/dynein-mediated transport of both Crb protein and its transcripts to the apical domain to control epithelial apico-basal (A/B) polarity.


Assuntos
Proteínas de Drosophila , Animais , Polaridade Celular , Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Complexo Dinactina/metabolismo , Dineínas/metabolismo , Células Epiteliais/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo
8.
Plant J ; 119(1): 460-477, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38678554

RESUMO

Maize plastid terminal oxidase1 (ZmPTOX1) plays a pivotal role in seed development by upholding redox balance within seed plastids. This study focuses on characterizing the white kernel mutant 3735 (wk3735) mutant, which yields pale-yellow seeds characterized by heightened protein but reduced carotenoid levels, along with delayed germination compared to wild-type (WT) seeds. We successfully cloned and identified the target gene ZmPTOX1, responsible for encoding maize PTOX-a versatile plastoquinol oxidase and redox sensor located in plastid membranes. While PTOX's established role involves regulating redox states and participating in carotenoid metabolism in Arabidopsis leaves and tomato fruits, our investigation marks the first exploration of its function in storage organs lacking a photosynthetic system. Through our research, we validated the existence of plastid-localized ZmPTOX1, existing as a homomultimer, and established its interaction with ferredoxin-NADP+ oxidoreductase 1 (ZmFNR1), a crucial component of the electron transport chain (ETC). This interaction contributes to the maintenance of redox equilibrium within plastids. Our findings indicate a propensity for excessive accumulation of reactive oxygen species (ROS) in wk3735 seeds. Beyond its known role in carotenoids' antioxidant properties, ZmPTOX1 also impacts ROS homeostasis owing to its oxidizing function. Altogether, our results underscore the critical involvement of ZmPTOX1 in governing seed development and germination by preserving redox balance within the seed plastids.


Assuntos
Germinação , Homeostase , Oxirredução , Proteínas de Plantas , Plastídeos , Sementes , Zea mays , Sementes/crescimento & desenvolvimento , Sementes/genética , Sementes/metabolismo , Germinação/genética , Plastídeos/metabolismo , Plastídeos/genética , Plastídeos/enzimologia , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo , Zea mays/enzimologia , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Oxirredutases/metabolismo , Oxirredutases/genética , Regulação da Expressão Gênica de Plantas , Carotenoides/metabolismo
9.
FASEB J ; 38(13): e23762, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38923643

RESUMO

Exosomes play significant roles in the communications between tumor cells and tumor microenvironment. However, the specific mechanisms by which exosomes modulate tumor development under hypoxia in pancreatic neuroendocrine tumors (pNETs) are not well understood. This study aims to investigate these mechanisms and made several important discoveries. We found that hypoxic exosomes derived from pNETs cells can activate tumor-associated macrophages (TAM) to the M2 phenotype, in turn, the M2-polarized TAM, facilitate the migration and invasion of pNETs cells. Further investigation revealed that CEACAM5, a protein highly expressed in hypoxic pNETs cells, is enriched in hypoxic pNETs cell-derived exosomes. Hypoxic exosomal CEACAM5 was observed to induce M2 polarization of TAM through activation of the MAPK signaling pathway. Coculturing pNETs cells with TAM or treated with hypoxic exosomes enhanced the metastatic capacity of pNETs cells. In conclusion, these findings suggest that pNETs cells generate CEACAM5-rich exosomes in a hypoxic microenvironment, which in turn polarize TAM promote malignant invasion of pNETs cells. Targeting exosomal CEACAM5 could potentially serve as a diagnostic and therapeutic strategy for pNETs.


Assuntos
Antígenos CD , Exossomos , Proteínas Ligadas por GPI , Metaloproteinase 9 da Matriz , Tumores Neuroendócrinos , Neoplasias Pancreáticas , Microambiente Tumoral , Macrófagos Associados a Tumor , Exossomos/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Humanos , Animais , Tumores Neuroendócrinos/metabolismo , Tumores Neuroendócrinos/patologia , Metaloproteinase 9 da Matriz/metabolismo , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/patologia , Camundongos , Linhagem Celular Tumoral , Antígenos CD/metabolismo , Proteínas Ligadas por GPI/metabolismo , Moléculas de Adesão Celular/metabolismo , Movimento Celular , Metástase Neoplásica , Camundongos Nus , Hipóxia/metabolismo , Hipóxia Celular/fisiologia , Antígeno Carcinoembrionário
10.
Nucleic Acids Res ; 51(D1): D1122-D1128, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36330927

RESUMO

Deciphering the fine-scale molecular mechanisms that shape the genetic effects at disease-associated loci from genome-wide association studies (GWAS) remains challenging. The key avenue is to identify the essential molecular phenotypes that mediate the causal variant and disease under particular biological conditions. Therefore, integrating GWAS signals with context-specific quantitative trait loci (QTLs) (such as different tissue/cell types, disease states, and perturbations) from extensive molecular phenotypes would present important strategies for full understanding of disease genetics. Via persistent curation and systematic data processing of large-scale human molecular trait QTLs (xQTLs), we updated our previous QTLbase database (now QTLbase2, http://mulinlab.org/qtlbase) to comprehensively analyze and visualize context-specific QTLs across 22 molecular phenotypes and over 95 tissue/cell types. Overall, the resource features the following major updates and novel functions: (i) 960 more genome-wide QTL summary statistics from 146 independent studies; (ii) new data for 10 previously uncompiled QTL types; (iii) variant query scope expanded to fit 195 QTL datasets based on whole-genome sequencing; (iv) supports filtering and comparison of QTLs for different biological conditions, such as stimulation types and disease states; (v) a new linkage disequilibrium viewer to facilitate variant prioritization across tissue/cell types and QTL types.


Assuntos
Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Humanos , Mapeamento Cromossômico , Desequilíbrio de Ligação , Fenótipo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas/genética , Catálogos como Assunto
11.
Nucleic Acids Res ; 51(15): 7832-7850, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37403778

RESUMO

Maize (Zea mays) kernel size is an important factor determining grain yield; although numerous genes regulate kernel development, the roles of RNA polymerases in this process are largely unclear. Here, we characterized the defective kernel 701 (dek701) mutant that displays delayed endosperm development but normal vegetative growth and flowering transition, compared to its wild type. We cloned Dek701, which encoded ZmRPABC5b, a common subunit to RNA polymerases I, II and III. Loss-of-function mutation of Dek701 impaired the function of all three RNA polymerases and altered the transcription of genes related to RNA biosynthesis, phytohormone response and starch accumulation. Consistent with this observation, loss-of-function mutation of Dek701 affected cell proliferation and phytohormone homeostasis in maize endosperm. Dek701 was transcriptionally regulated in the endosperm by the transcription factor Opaque2 through binding to the GCN4 motif within the Dek701 promoter, which was subjected to strong artificial selection during maize domestication. Further investigation revealed that DEK701 interacts with the other common RNA polymerase subunit ZmRPABC2. The results of this study provide substantial insight into the Opaque2-ZmRPABC5b transcriptional regulatory network as a central hub for regulating endosperm development in maize.


Assuntos
RNA Polimerases Dirigidas por DNA , Endosperma , Zea mays , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Endosperma/genética , Endosperma/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Zea mays/genética , Zea mays/metabolismo
12.
Proc Natl Acad Sci U S A ; 119(6)2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35115400

RESUMO

Stem cells constantly divide and differentiate to maintain adult tissue homeostasis, and uncontrolled stem cell proliferation leads to severe diseases such as cancer. How stem cell proliferation is precisely controlled remains poorly understood. Here, from an RNA interference (RNAi) screen in adult Drosophila intestinal stem cells (ISCs), we identify a factor, Yun, required for proliferation of normal and transformed ISCs. Yun is mainly expressed in progenitors; our genetic and biochemical evidence suggest that it acts as a scaffold to stabilize the Prohibitin (PHB) complex previously implicated in various cellular and developmental processes and diseases. We demonstrate that the Yun/PHB complex is regulated by and acts downstream of EGFR/MAPK signaling. Importantly, the Yun/PHB complex interacts with and positively affects the levels of the transcription factor E2F1 to regulate ISC proliferation. In addition, we find that the role of the PHB complex in cell proliferation is evolutionarily conserved. Thus, our study uncovers a Yun/PHB-E2F1 regulatory axis in stem cell proliferation.


Assuntos
Células-Tronco Adultas/metabolismo , Proliferação de Células/fisiologia , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Fator de Transcrição E2F1/metabolismo , Intestinos/metabolismo , Proibitinas/metabolismo , Animais , Animais Geneticamente Modificados , Diferenciação Celular/fisiologia , Homeostase/fisiologia , Interferência de RNA/fisiologia , Transdução de Sinais/fisiologia
13.
Am J Physiol Cell Physiol ; 326(6): C1590-C1603, 2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38586878

RESUMO

Muscular fatty infiltration is a common issue after rotator cuff tears (RCTs), which impair shoulder function. Females suffer a higher prevalence and a more severe degree of muscular fatty infiltration after RCT when compared with males, with the underlying mechanisms remaining unclear. Fibro-adipogenic progenitors (FAPs) are the primary source of muscular fatty infiltration following RCT. Our findings disclose that gender-specific disparities in muscular fatty infiltration are linked to mTOR/ULK1-mediated autophagy of FAPs. Decreased autophagic activity contributes to adipogenic differentiation in female FAPs after RCT. Furthermore, metformin could enhance mTOR/ULK1-mediated autophagic processes of FAPs, thereby alleviating fatty infiltration and improving shoulder functionality after RCT. Together, our study reveals that gender differences in muscular fatty infiltration arise from distinct autophagic activities. Metformin could be a promising noninvasive intervention to ameliorate muscular fatty infiltration of RCT.NEW & NOTEWORTHY The current study demonstrated that gender-specific disparities in muscular fatty infiltration are attributed to mTOR/ULK1-mediated autophagy of FAPs. Decreased autophagic activity contributes to adipogenic differentiation in female FAPs after RCT. Moreover, metformin could enhance mTOR/ULK1-mediated autophagic processes of FAPs, thereby alleviating fatty infiltration and improving shoulder functionality after RCT. Therefore, metformin could be a promising noninvasive intervention to ameliorate muscular fatty infiltration of RCT.


Assuntos
Adipogenia , Proteína Homóloga à Proteína-1 Relacionada à Autofagia , Autofagia , Metformina , Lesões do Manguito Rotador , Serina-Treonina Quinases TOR , Animais , Autofagia/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Metformina/farmacologia , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Lesões do Manguito Rotador/metabolismo , Lesões do Manguito Rotador/patologia , Lesões do Manguito Rotador/tratamento farmacológico , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Diferenciação Celular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
14.
Biochem Cell Biol ; 2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39393088

RESUMO

Enterotoxigenic Escherichia coli (ETEC) is a major cause of diarrhea in humans and animals. The study aimed to evaluate the efficacy of bLf as an adjuvant combined with AMP (N6) in the treatment of E. coli-induced bacterial enteritis. Sixty female ICR mice were randomly divided into six groups: CK group, NC group:(infected and untreated), N6 treatment group (20 mg/kg), bLf treatment group (100 mg/kg), bLf+ N6-A treatment group (10 mg/kg N6+100 mg/kg bLf) and bLf+N6- b group (20 mg/kg N6+100 mg/kg bLf), the clinical symptoms, intestinal morphology, inflammatory response and serum metabolites were monitored. The results showed that: compared with the NC group, the bLf-N6-A and bLf-N6-B treatment groups had significant reductions in TNF-α and IL-6, significant increases in IL-10, and significant reductions in endotoxin and DAO in plasma (p<0.05). Meanwhile, the bLf-N6-A and bLf-N6-B treatment groups significantly increased the expression of ZO-1, claudin-1 and occludin, increased the height of small intestinal mucosal villi and VH/CD after ETEC K88-induced intestinal injury (p<0.05). The supplementation of bLf and N6 relieved enteritis by balancing intestinal mucosal immunity, improving intestinal morphology and barrier function. BLf combined with N6 can be used as an effective therapeutic strategy for the treatment of bacterial enteritis.

15.
Anal Chem ; 96(1): 427-436, 2024 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-38102083

RESUMO

The worldwide antimicrobial resistance (AMR) dilemma urgently requires rapid and accurate pathogen phenotype discrimination and antibiotic resistance identification. The conventional protocols are either time-consuming or depend on expensive instrumentations. Herein, we demonstrate a metabolic-labeling-assisted chemical nose strategy for phenotyping classification and antibiotic resistance identification of pathogens based on the "antibiotic-responsive spectrum" of different pathogens. d-Amino acids with click handles were metabolically incorporated into the cell wall of pathogens for further clicking with dibenzocyclooctyne-functionalized upconversion nanoparticles (DBCO-UCNPs) in the presence/absence of six types of antibiotics, which generates seven-channel sensing responses. With the assistance of machine learning algorithms, eight types of pathogens, including three types of antibiotic-resistant bacteria, can be well classified and discriminated in terms of microbial taxonomies, Gram phenotypes, and antibiotic resistance. The present metabolic-labeling-assisted strategy exhibits good anti-interference capability and improved discrimination ability rooted in the unique sensing mechanism. Sensitive identification of pathogens with 100% accuracy from artificial urinary tract infection samples at a concentration as low as 105 CFU/mL was achieved. Pathogens outside of the training set can also be discriminated well. This clearly demonstrated the potential of the present strategy in the identification of unknown pathogens in clinical samples.


Assuntos
Antibacterianos , Bactérias , Antibacterianos/farmacologia , Resistência Microbiana a Medicamentos , Algoritmos , Testes de Sensibilidade Microbiana
16.
Anal Chem ; 96(32): 13270-13277, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39093913

RESUMO

Epithelial-mesenchymal transition (EMT) is a complex process that plays a critical role in tumor progression. In this study, we present an EMT sensing panel for the classification of cancer cells at different EMT stages. This sensing panel consists of three types of fluorescent probes based on boronic acid-functionalized carbon-nitride nanosheet (BCN) derivatives. The selective response toward different EMT-associated biomarkers, namely, EpCAM, N-cadherin, and sialic acid (SA), was achieved by conjugating the corresponding antibodies to each BCN derivative, whereas the rare-earth-doping ensures simultaneous sensing of the three biomarkers with fluorescent emission of the three probes at different wavelengths. Sensitive sensing of the three biomarkers was achieved at the protein level with LODs reaching 1.35 ng mL-1 for EpCAM, 1.62 ng mL-1 for N-cadherin, and 1.54 ng mL-1 for SA. The selective response of these biomarkers on the cell surface also facilitated sensitive detection of MCF-7 cells and MDA-MB-231 cells with LODs of 2 cells/mL and 2 cells/mL, respectively. Based on the simultaneous sensing of the three biomarkers on cancer cells that underwent different extents of EMT, precise discrimination and classification of cells at various EMT stages were also achieved with an accuracy of 93.3%. This EMT sensing panel provided a versatile tool for monitoring the EMT evolution process and has the potential to be used for the evaluation of the EMT-targeting therapy and metastasis prediction.


Assuntos
Biomarcadores Tumorais , Caderinas , Transição Epitelial-Mesenquimal , Humanos , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Caderinas/análise , Caderinas/metabolismo , Corantes Fluorescentes/química , Linhagem Celular Tumoral , Molécula de Adesão da Célula Epitelial/metabolismo , Células MCF-7 , Ácidos Borônicos/química , Ácido N-Acetilneuramínico/análise , Ácido N-Acetilneuramínico/metabolismo
17.
Anal Chem ; 96(26): 10800-10808, 2024 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-38904228

RESUMO

Tumor-derived extracellular vesicles (TEVs) are rich in cellular information and hold great promise as a biomarker for noninvasive cancer diagnosis. However, accurate measurement of TEVs presents challenges due to their low abundance and potential interference from a high number of EVs derived from normal cells. Herein, an aptamer-proximity-ligation-activated rolling circle amplification (RCA) method for EV membrane recognition, coupled with single particle inductively coupled plasma mass spectrometry (sp-ICP-MS) for the quantification of TEVs, is developed. When DNA-labeled ultrasmall gold nanoparticle (AuNP) probes bind to the long chains formed by RCA, they aggregate to form large particles. Notably, small AuNPs scarcely produce pulse signals in sp-ICP-MS, thereby detecting TEVs in a wash-free manner. By leveraging the strong binding affinity of aptamers, dual aptamers for EpCAM and PD-L1 recognition, and the sp-ICP-MS technique, this method offers remarkable sensitivity and selectivity in tracing TEVs. Under optimized conditions, the present method shows a favorable linear relationship between the pulse signal frequency of sp-ICP-MS and TEV concentration within the range of 105-107 particles/mL, along with a detection limit of 1.1 × 104 particles/mL. The pulse signals from sp-ICP-MS combined with machine learning algorithms are used to discriminate cancer patients from healthy donors with 100% accuracy. Due to its simple and fast operation and excellent sensitivity and accuracy, this approach holds significant potential for diverse applications in life sciences and personalized medicine.


Assuntos
Aptâmeros de Nucleotídeos , Vesículas Extracelulares , Ouro , Espectrometria de Massas , Nanopartículas Metálicas , Técnicas de Amplificação de Ácido Nucleico , Humanos , Aptâmeros de Nucleotídeos/química , Vesículas Extracelulares/química , Técnicas de Amplificação de Ácido Nucleico/métodos , Nanopartículas Metálicas/química , Ouro/química , Espectrometria de Massas/métodos , Neoplasias , Molécula de Adesão da Célula Epitelial/metabolismo , Limite de Detecção
18.
Anal Chem ; 96(4): 1742-1749, 2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38221770

RESUMO

Speciation analysis of arsenic in urine is essential for the studies of arsenic metabolism and biological effects, but the unstable arsenic species represented by MMAIII and DMAIII pose a huge challenge to analytical accuracy. Herein, a novel urine self-sampling (USS) kit combined with an automated preparation-sampler (APS) device is rationally designed and used for convenient analysis of arsenic metabolites by high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS). The subject can collect urine into a sampling vial at home and use a homemade syringe to pump argon to displace oxygen in the vial, thereby inhibiting the oxidation of MMAIII and DMAIII. After USS and transportation, the sampling vial is loaded directly onto the APS device, where the urine sample can be automatically mixed with diluent, filtered, and loaded into HPLC-ICPMS for arsenic speciation analysis under anaerobic conditions. For a single sample, the sampling time and the analysis time are <8 and <18 min, respectively. The recoveries of MMAIII and DMAIII in urine over 24 h at 4 °C are 86 and 67%, surpassing the conventional sampling method by 28 and 67%, respectively. When the APS is coupled to HPLC-ICPMS, the detection limits of AsC, iAsIII, MMAIII, DMAV, MMAV, DMAIII, and iAsV are 0.03-0.10 µg L-1 with precisions of <10%. The present method provides a convenient and reliable tool for the storage and analysis of unstable arsenic species in urine and lays the foundation for studying the metabolic and biological effects of methylated trivalent arsenicals.


Assuntos
Arsênio , Arsenicais , Compostos Organometálicos , Arsênio/análise , Arsenicais/análise , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas/métodos
19.
Anal Chem ; 96(18): 7155-7162, 2024 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-38652710

RESUMO

Microplastics (MPs) can act as carriers of environmental arsenic species into the stomach with food and release arsenic species during digestion, which threatens human health. Herein, an integrated dynamic stomach model (DSM)-capillary electrophoresis-inductively coupled plasma mass spectrometry (CE-ICPMS) is developed for online monitoring of the release and transformation behaviors of arsenic species loaded on MPs (As-MPs) in the simulated human stomach. The 3D-printed DSM with a soft stomach chamber enables the behaviors of gastric peristalsis, gastric and salivary fluid addition, pH adjustment, and gastric emptying (GE) to be controlled by a self-written program after oral ingestion of food with As-MPs. The gastric extract during digestion is introduced into the spiral channel to remove the large particulate impurity and online filtered to obtain the clarified arsenic-containing solution for subsequent speciation analysis of arsenic by CE-ICPMS. The digestion conditions and pretreatment processes of DSM are tracked and validated, and the release rates of As-MPs digested by DSM are compared with those digested by the static stomach model and DSM without GE. The release rate of inorganic arsenic on MPs is higher than that of organic arsenic throughout the gastric digestion process, and 8% of As(V) is reduced to As(III). The detection limits for As(III), DMA, MMA, and As(V) are 0.5-0.9 µg L-1 using DSM-CE-ICPMS, along with precisions of ≤8%. This present method provides an integrated and convenient tool for evaluating the release and transformation of As-MPs during human gastric digestion and provides a reference for exploring the interactions between MPs and metals/metalloids in the human body.


Assuntos
Arsênio , Eletroforese Capilar , Espectrometria de Massas , Microplásticos , Estômago , Arsênio/análise , Humanos , Espectrometria de Massas/métodos , Eletroforese Capilar/métodos , Microplásticos/análise , Estômago/química , Digestão , Modelos Biológicos
20.
Anal Chem ; 96(24): 10046-10055, 2024 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-38845359

RESUMO

Extracellular vesicle (EV) molecular phenotyping offers enormous opportunities for cancer diagnostics. However, the majority of the associated studies adopted biomarker-based unimodal analysis to achieve cancer diagnosis, which has high false positives and low precision. Herein, we report a multimodal platform for the high-precision diagnosis of bladder cancer (BCa) through a multispectral 3D DNA machine in combination with a multimodal machine learning (ML) algorithm. The DNA machine was constructed using magnetic microparticles (MNPs) functionalized with aptamers that specifically identify the target of interest, i.e., five protein markers on bladder-cancer-derived urinary EVs (uEVs). The aptamers were hybridized with DNA-stabilized silver nanoclusters (DNA/AgNCs) and a G-quadruplex/hemin complex to form a sensing module. Such a DNA machine ensured multispectral detection of protein markers by fluorescence (FL), inductively coupled plasma mass spectrometry (ICP-MS), and UV-vis absorption (Abs). The obtained data sets then underwent uni- or multimodal ML for BCa diagnosis to compare the analytical performance. In this study, urine samples were obtained from our prospective cohort (n = 45). Our analytical results showed that the 3D DNA machine provided a detection limit of 9.2 × 103 particles mL-1 with a linear range of 4 × 104 to 5 × 107 particles mL-1 for uEVs. Moreover, the multimodal data fusion model exhibited an accuracy of 95.0%, a precision of 93.1%, and a recall rate of 93.2% on average, while those of the three types of unimodal models were no more than 91%. The elevated diagnosis precision by using the present fusion platform offers a perspective approach to diminishing the rate of misdiagnosis and overtreatment of BCa.


Assuntos
Aprendizado de Máquina , Neoplasias da Bexiga Urinária , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/urina , Humanos , Biomarcadores Tumorais/urina , Biomarcadores Tumorais/análise , DNA/química , Prata/química , Aptâmeros de Nucleotídeos/química , Vesículas Extracelulares/química , Nanopartículas Metálicas/química
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