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1.
Development ; 150(16)2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37526610

RESUMO

Drosophila is an important model for studying heart development and disease. Yet, single-cell transcriptomic data of its developing heart have not been performed. Here, we report single-cell profiling of the entire fly heart using ∼3000 Hand-GFP embryos collected at five consecutive developmental stages, ranging from bilateral migrating rows of cardiac progenitors to a fused heart tube. The data revealed six distinct cardiac cell types in the embryonic fly heart: cardioblasts, both Svp+ and Tin+ subtypes; and five types of pericardial cell (PC) that can be distinguished by four key transcription factors (Eve, Odd, Ct and Tin) and include the newly described end of the line PC. Notably, the embryonic fly heart combines transcriptional signatures of the mammalian first and second heart fields. Using unique markers for each heart cell type, we defined their number and location during heart development to build a comprehensive 3D cell map. These data provide a resource to track the expression of any gene in the developing fly heart, which can serve as a reference to study genetic perturbations and cardiac diseases.


Assuntos
Drosophila melanogaster , Drosophila melanogaster/citologia , Drosophila melanogaster/embriologia , Coração/embriologia , Análise da Expressão Gênica de Célula Única , Linfonodos/citologia , Linfonodos/embriologia , Embrião não Mamífero , Desenvolvimento Embrionário , Biomarcadores , Organogênese
2.
Proc Natl Acad Sci U S A ; 119(49): e2209884119, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36454759

RESUMO

Cone photoreceptor diversity allows detection of wavelength information in light, the first step in color (chromatic) vision. In most mammals, cones express opsin photopigments for sensitivity to medium/long (M, "green") or short (S, "blue") wavelengths and are differentially arrayed over the retina. Cones appear early in retinal neurogenesis but little is understood of the subsequent control of diversity of these postmitotic neurons, because cone populations are sparse and, apart from opsins, poorly defined. It is also a challenge to distinguish potentially subtle differences between cell subtypes within a lineage. Therefore, we derived a Cre driver to isolate individual M and S opsin-enriched cones, which are distributed in counter-gradients over the mouse retina. Fine resolution transcriptome analyses identified expression gradients for groups of genes. The postnatal emergence of gradients indicated divergent differentiation of cone precursors during maturation. Using genetic tagging, we demonstrated a role for thyroid hormone receptor ß2 (TRß2) in control of gradient genes, many of which are enriched for TRß2 binding sites and TRß2-regulated open chromatin. Deletion of TRß2 resulted in poorly distinguished cones regardless of retinal location. We suggest that TRß2 controls a bipotential transcriptional state to promote cone diversity and the chromatic potential of the species.


Assuntos
Receptores dos Hormônios Tireóideos , Células Fotorreceptoras Retinianas Cones , Animais , Camundongos , Regulação da Expressão Gênica , Opsinas/genética , Retina , Opsinas de Bastonetes/genética
3.
J Am Chem Soc ; 146(28): 19019-19029, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38963153

RESUMO

Photocatalysis has emerged as an effective tool for addressing the contemporary challenges in organic synthesis. However, the trial-and-error-based screening of feasible substrates and optimal reaction conditions remains time-consuming and potentially expensive in industrial practice. Here, we demonstrate an electrochemical-based data-acquisition approach that derives a simple set of redox-relevant electro-descriptors for effective mechanistic analysis and performance evaluation through machine learning (ML) in photocatalytic synthesis. These electro-descriptors correlate to the quantification of shifted charge transfer processes in response to the photoirradiation and enabled construction of reactivity diagram where high-yield reactive "hot zones" can reflect subtle changes of the reaction system. For the model reaction of photocatalytic deoxygenation reaction, the influence of varying carboxylic acids (substrate A, oxidation-intended) and alkenes (substrate B, reduction-intended) and varying reaction conditions on the reaction yield can be visualized, while mathematical analysis of the electro-descriptor patterns further revealed distinct mechanistic/kinetic impacts from different substrates and conditions. Additionally, in the application of ML algorithms, the experimentally derived electro-descriptors reflect an overall redox kinetic outcome contributed from vast reaction parameters, serving as a capable means to reduce the dimensionality in the case of complex multiparameter chemical space. As a result, utilization of electro-descriptors enabled efficient and robust quantitative evaluation of chemical reactivity, demonstrating promising potential of introducing operando-relevant experimental insights in the data-driven chemistry.

4.
Gut ; 72(1): 153-167, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35361683

RESUMO

OBJECTIVE: A comprehensive immune landscape for HBV infection is pivotal to achieve HBV cure. DESIGN: We performed single-cell RNA sequencing of 2 43 000 cells from 46 paired liver and blood samples of 23 individuals, including six immune tolerant, 5 immune active (IA), 3 acute recovery (AR), 3 chronic resolved and 6 HBV-free healthy controls (HCs). Flow cytometry and histological assays were applied in a second HBV cohort for validation. RESULTS: Both IA and AR were characterised by high levels of intrahepatic exhausted CD8+ T (Tex) cells. In IA, Tex cells were mainly derived from liver-resident GZMK+ effector memory T cells and self-expansion. By contrast, peripheral CX3CR1+ effector T cells and GZMK+ effector memory T cells were the main source of Tex cells in AR. In IA but not AR, significant cell-cell interactions were observed between Tex cells and regulatory CD4+ T cells, as well as between Tex and FCGR3A+ macrophages. Such interactions were potentially mediated through human leukocyte antigen class I molecules together with their receptors CANX and LILRBs, respectively, contributing to the dysfunction of antiviral immune responses. By contrast, CX3CR1+GNLY+ central memory CD8+ T cells were concurrently expanded in both liver and blood of AR, providing a potential surrogate marker for viral resolution. In clinic, intrahepatic Tex cells were positively correlated with serum alanine aminotransferase levels and histological grading scores. CONCLUSION: Our study dissects the coordinated immune responses for different HBV infection phases and provides a rich resource for fully understanding immunopathogenesis and developing effective therapeutic strategies.


Assuntos
Linfócitos T CD8-Positivos , Fígado , Humanos , Fígado/patologia , Antivirais , Linfócitos T Reguladores , Análise de Sequência de RNA , Vírus da Hepatite B
5.
Dev Biol ; 490: 53-65, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35853502

RESUMO

Mammalian KMT2C, KMT2D, and HCFC1 are expressed during heart development and have been associated with congenital heart disease, but their roles in heart development remain elusive. We found that the Drosophila Lpt and trr genes encode the N-terminal and C-terminal homologs, respectively, of mammalian KMT2C or KMT2D. Lpt and trr mutant embryos showed reduced cardiac progenitor cells. Silencing of Lpt, trr, or both simultaneously in the heart led to similar abnormal cardiac morphology, tissue fibrosis, and cardiac functional defects. Like KMT2D, Lpt and trr were found to modulate histone H3K4 mono- and dimethylation, but not trimethylation. Investigation of downstream genes regulated by mouse KMT2D in the heart showed that their fly homologs are similarly regulated by Lpt or trr in the fly heart, suggesting that Lpt and trr regulate an evolutionarily conserved transcriptional network for heart development. Moreover, we showed that cardiac silencing of Hcf, the fly homolog of mammalian HCFC1, leads to heart defects similar to those observed in Lpt and trr silencing, as well as reduced H3K4 monomethylation. Our findings suggest that Lpt and trr function together to execute the conserved function of mammalian KMT2C and KMT2D in histone H3 lysine K4 mono- and dimethylation required for heart development. Possibly aided by Hcf, which we show plays a related role in H3K4 methylation during fly heart development.


Assuntos
Proteínas de Drosophila , Histona-Lisina N-Metiltransferase , Histonas , Coativadores de Receptor Nuclear , Animais , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Metilação , Camundongos , Coativadores de Receptor Nuclear/genética , Coativadores de Receptor Nuclear/metabolismo
6.
Environ Sci Technol ; 57(27): 9955-9964, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37336722

RESUMO

Extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae has caused a global pandemic with high prevalence in livestock and poultry, which could disseminate into the environment and humans. To curb this risk, heat-based harmless treatment of livestock waste was carried out. However, some risks of the bacterial persistence have not been thoroughly assessed. This study demonstrated that antibiotic-resistant bacteria (ARB) could survive at 55 °C through dormancy, and simultaneously transformable extracellular antibiotic resistance genes (eARGs) would be released. The ESBL-producing pathogenic Escherichia coli CM1 from chicken manure could enter a dormant state at 55 °C and reactivate at 37 °C. Dormant CM1 had stronger ß-lactam resistance, which was associated with high expression of ß-lactamase genes and low expression of outer membrane porin genes. Resuscitated CM1 maintained its virulence expression and multidrug resistance and even had stronger cephalosporin resistance, which might be due to the ultra-low expression of the porin genes. Besides, heat at 55 °C promoted the release of eARGs, some of which possessed a certain nuclease stability and heat persistence, and even maintained their transformability to an Acinetobacter baylyi strain. Therefore, dormant multidrug-resistant pathogens from livestock waste will still pose a direct health risk to humans, while the resuscitation of dormant ARB and the transformation of released eARGs will jointly promote the proliferation of ARGs and the spread of antibiotic resistance.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Animais , Humanos , Escherichia coli/genética , Escherichia coli/metabolismo , Gado/metabolismo , Gado/microbiologia , Temperatura Alta , Antagonistas de Receptores de Angiotensina/uso terapêutico , Antibacterianos/farmacologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , beta-Lactamases/genética , Resistência Microbiana a Medicamentos/genética
7.
J Am Soc Nephrol ; 31(5): 1024-1034, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32238475

RESUMO

BACKGROUND: Studies have linked mutations in genes encoding the eight-protein exocyst protein complex to kidney disease, but the underlying mechanism is unclear. Because Drosophila nephrocytes share molecular and structural features with mammalian podocytes, they provide an efficient model for studying this issue. METHODS: We silenced genes encoding exocyst complex proteins specifically in Drosophila nephrocytes and studied the effects on protein reabsorption by lacuna channels and filtration by the slit diaphragm. We performed nephrocyte functional assays, carried out super-resolution confocal microscopy of slit diaphragm proteins, and used transmission electron microscopy to analyze ultrastructural changes. We also examined the colocalization of slit diaphragm proteins with exocyst protein Sec15 and with endocytosis and recycling regulators Rab5, Rab7, and Rab11. RESULTS: Silencing exocyst genes in nephrocytes led to profound changes in structure and function. Abolition of cellular accumulation of hemolymph proteins with dramatically reduced lacuna channel membrane invaginations offered a strong indication of reabsorption defects. Moreover, the slit diaphragm's highly organized surface structure-essential for filtration-was disrupted, and key proteins were mislocalized. Ultrastructural analysis revealed that exocyst gene silencing led to the striking appearance of novel electron-dense structures that we named "exocyst rods," which likely represent accumulated membrane proteins following defective exocytosis or recycling. The slit diaphragm proteins partially colocalized with Sec15, Rab5, and Rab11. CONCLUSIONS: Our findings suggest that the slit diaphragm of Drosophila nephrocytes requires balanced endocytosis and recycling to maintain its structural integrity and that impairment of the exocyst complex leads to disruption of the slit diaphragm and nephrocyte malfunction. This model may help identify therapeutic targets for treating kidney diseases featuring molecular defects in vesicle endocytosis, exocytosis, and recycling.


Assuntos
Proteínas de Drosophila/fisiologia , Drosophila melanogaster/citologia , Endocitose , Proteínas de Membrana/metabolismo , Complexos Multiproteicos/fisiologia , Podócitos/metabolismo , Proteínas de Transporte Vesicular/fisiologia , Animais , Animais Geneticamente Modificados , Fator Natriurético Atrial/metabolismo , Forma Celular , Dextranos/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Inativação Gênica , Hemolinfa/metabolismo , Camundongos , Complexos Multiproteicos/genética , Podócitos/ultraestrutura , Proteínas de Transporte Vesicular/genética
8.
J Am Soc Nephrol ; 30(5): 840-853, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30910934

RESUMO

BACKGROUND: Studies have identified mutations in >50 genes that can lead to monogenic steroid-resistant nephrotic syndrome (SRNS). The NUP160 gene, which encodes one of the protein components of the nuclear pore complex nucleoporin 160 kD (Nup160), is expressed in both human and mouse kidney cells. Knockdown of NUP160 impairs mouse podocytes in cell culture. Recently, siblings with SRNS and proteinuria in a nonconsanguineous family were found to carry compound-heterozygous mutations in NUP160. METHODS: We identified NUP160 mutations by whole-exome and Sanger sequencing of genomic DNA from a young girl with familial SRNS and FSGS who did not carry mutations in other genes known to be associated with SRNS. We performed in vivo functional validation studies on the NUP160 mutations using a Drosophila model. RESULTS: We identified two compound-heterozygous NUP160 mutations, NUP160R1173× and NUP160E803K . We showed that silencing of Drosophila NUP160 specifically in nephrocytes (fly renal cells) led to functional abnormalities, reduced cell size and nuclear volume, and disorganized nuclear membrane structure. These defects were completely rescued by expression of the wild-type human NUP160 gene in nephrocytes. By contrast, expression of the NUP160 mutant allele NUP160R1173× completely failed to rescue nephrocyte phenotypes, and mutant allele NUP160E803K rescued only nuclear pore complex and nuclear lamin localization defects. CONCLUSIONS: Mutations in NUP160 are implicated in SRNS. Our findings indicate that NUP160 should be included in the SRNS diagnostic gene panel to identify additional patients with SRNS and homozygous or compound-heterozygous NUP160 mutations and further strengthen the evidence that NUP160 mutations can cause SRNS.


Assuntos
Resistência a Medicamentos , Mutação/genética , Síndrome Nefrótica/genética , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Proteinúria/genética , Esteroides/administração & dosagem , Criança , Feminino , Predisposição Genética para Doença , Humanos , Síndrome Nefrótica/diagnóstico , Síndrome Nefrótica/tratamento farmacológico , Fenótipo , Prognóstico , Medição de Risco
9.
Am J Physiol Renal Physiol ; 317(6): F1593-F1604, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31566424

RESUMO

Podocyte function is tightly linked to the complex organization of its cytoskeleton and adhesion to the underlying glomerular basement membrane. Adhesion of cultured podocytes to a variety of substrates is reported to correlate with podocyte health. To identify novel genes that are important for podocyte function, we designed an in vitro genetic screen based on podocyte adhesion to plates coated with either fibronectin or soluble Fms-like tyrosine kinase-1 (sFLT1)/Fc. A genome-scale pooled RNA interference screen on immortalized human podocytes identified 77 genes that increased adhesion to fibronectin, 101 genes that increased adhesion to sFLT1/Fc, and 44 genes that increased adhesion to both substrates when knocked down. Multiple shRNAs against diphthamide biosynthesis protein 1-4 (DPH1-DPH4) were top hits for increased adhesion. Immortalized human podocyte cells stably expressing these hairpins displayed increased adhesion to both substrates. We then used CRISPR-Cas9 to generate podocyte knockout cells for DPH1, DPH2, or DPH3, which also displayed increased adhesion to both fibronectin and sFLT1/Fc, as well as a spreading defect. Finally, we showed that Drosophila nephrocyte-specific knockdown of Dph1, Dph2, and Dph4 resulted in altered nephrocyte function. In summary, we report here a novel high-throughput method to identify genes important for podocyte function. Given the central role of podocyte adhesion as a marker of podocyte health, these data are a rich source of candidate regulators of glomerular disease.


Assuntos
Adesão Celular/genética , Adesão Celular/fisiologia , Histidina/análogos & derivados , Rim/metabolismo , Podócitos/metabolismo , Animais , Linhagem Celular , Drosophila , Fibronectinas/metabolismo , Proteínas de Choque Térmico HSP40/genética , Ensaios de Triagem em Larga Escala , Histidina/biossíntese , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Antígenos de Histocompatibilidade Menor/genética , Proteínas/genética , RNA Interferente Pequeno , Proteínas Supressoras de Tumor/genética , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética
10.
Hum Mol Genet ; 26(4): 768-780, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-28164240

RESUMO

Many genetic mutations have been identified as monogenic causes of nephrotic syndrome (NS), but important knowledge gaps exist in the roles of these genes in kidney cell biology and renal diseases. More animal models are needed to assess the functions of these genes in vivo, and to determine how they cause NS in a timely manner. Drosophila nephrocytes and human podocytes share striking similarities, but to what degree these known NS genes play conserved roles in nephrocytes remains unknown. Here we systematically studied 40 genes associated with NS, including 7 that have not previously been analysed for renal function in an animal model. We found that 85% of these genes are required for nephrocyte functions, suggesting that a majority of human genes known to be associated with NS play conserved roles in renal function from flies to humans. To investigate functional conservation in more detail, we focused on Cindr, the fly homolog of the human NS gene CD2AP. Silencing Cindr in nephrocytes led to dramatic nephrocyte functional impairment and shortened life span, as well as collapse of nephrocyte lacunar channels and effacement of nephrocyte slit diaphragms. These phenotypes could be rescued by expression of a wild-type human CD2AP gene, but not a mutant allele derived from a patient with CD2AP-associated NS. We conclude that the Drosophila nephrocyte can be used to elucidate clinically relevant molecular mechanisms underlying the pathogenesis of most monogenic forms of NS, and to efficiently generate personalized in vivo models of genetic renal diseases bearing patient-specific mutations.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas do Citoesqueleto/genética , Proteínas de Drosophila/genética , Rim/fisiopatologia , Proteínas dos Microfilamentos/genética , Síndrome Nefrótica/genética , Animais , Modelos Animais de Doenças , Drosophila melanogaster/genética , Inativação Gênica , Humanos , Mutação , Síndrome Nefrótica/fisiopatologia , Fenótipo , Podócitos/metabolismo , Podócitos/patologia
11.
Biochem Biophys Res Commun ; 507(1-4): 59-66, 2018 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-30409424

RESUMO

Adoptive immunotherapy using chimeric antigen receptors-modified T cells (CAR-T) is a promising approach for cancer treatment. However, CARs currently applied in the clinics cannot be effectively regulated and the safety of CAR-T cell therapies remains a major concern. To improve the safety of CAR-T cells, we designed a synthetic splitting CAR (ssCAR) that can regulate T cell functions exogenously. Epidermal growth factor receptor variant III (EGFRvIII) was used as a molecular target for ssCAR. Our results indicate that both EGFRvIII and small molecule are needed for the activation of the ssCAR-T cells. AP21967 dose-dependently increased the expression of T cell activation, production of cytokines and extent of cell lysis. In conclusion, the gene switch designed in this study allows for temporal and spatial control over engineered T cells in a dose-and time-dependent manner by AP21967. Our work demonstrates the feasibility and improved safety profile of this novel treatment approach.


Assuntos
Receptores ErbB/metabolismo , Glioblastoma/imunologia , Glioblastoma/terapia , Imunoterapia Adotiva , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T/imunologia , Relação Dose-Resposta Imunológica , Células HEK293 , Humanos , Células Jurkat , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Bibliotecas de Moléculas Pequenas/farmacologia , Linfócitos T/efeitos dos fármacos , Fatores de Tempo
12.
Appl Opt ; 57(11): 2890-2899, 2018 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-29714290

RESUMO

In this paper, new expressions of the channel-correlation coefficient and its components (the large- and small-scale channel-correlation coefficients) for a plane wave are derived for a horizontal link in moderate-to-strong non-Kolmogorov turbulence using a generalized effective atmospheric spectrum which includes finite-turbulence inner and outer scales and high-wave-number "bump". The closed-form expression of the average bit error rate (BER) of the coherent free-space optical communication system is derived using the derived channel-correlation coefficients and an α-µ distribution to approximate the sum of the square root of arbitrarily correlated Gamma-Gamma random variables. Analytical results are provided to investigate the channel correlation and evaluate the average BER performance. The validity of the proposed approximation is illustrated by Monte Carlo simulations. This work will help with further investigation of the fading correlation in spatial diversity systems.

13.
J Am Soc Nephrol ; 28(9): 2607-2617, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28428331

RESUMO

Clinical studies have identified patients with nephrotic syndrome caused by mutations in genes involved in the biosynthesis of coenzyme Q10 (CoQ10), a lipid component of the mitochondrial electron transport chain and an important antioxidant. However, the cellular mechanisms through which these mutations induce podocyte injury remain obscure. Here, we exploited the striking similarities between Drosophila nephrocytes and human podocytes to develop a Drosophila model of these renal diseases, and performed a systematic in vivo analysis assessing the role of CoQ10 pathway genes in renal function. Nephrocyte-specific silencing of Coq2, Coq6, and Coq8, which are genes involved in the CoQ10 pathway that have been associated with genetic nephrotic syndrome in humans, induced dramatic adverse changes in these cells. In particular, silencing of Coq2 led to an abnormal localization of slit diaphragms, collapse of lacunar channels, and more dysmorphic mitochondria. In addition, Coq2-deficient nephrocytes showed elevated levels of autophagy and mitophagy, increased levels of reactive oxygen species, and increased sensitivity to oxidative stress. Dietary supplementation with CoQ10 at least partially rescued these defects. Furthermore, expressing the wild-type human COQ2 gene specifically in nephrocytes rescued the defective protein uptake, but expressing the mutant allele derived from a patient with COQ2 nephropathy did not. We conclude that transgenic Drosophila lines carrying mutations in the CoQ10 pathway genes are clinically relevant models with which to explore the pathogenesis of podocyte injury and could serve as a new platform to test novel therapeutic approaches.


Assuntos
Alquil e Aril Transferases/genética , Síndrome Nefrótica/genética , Síndrome Nefrótica/metabolismo , Ubiquinona/análogos & derivados , Vitaminas/farmacologia , Alquil e Aril Transferases/deficiência , Alelos , Animais , Autofagia/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Modelos Animais de Doenças , Inativação Gênica , Humanos , Mitocôndrias/ultraestrutura , Mitofagia/efeitos dos fármacos , Organismos Geneticamente Modificados , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/genética , Ubiquinona/biossíntese , Ubiquinona/genética , Ubiquinona/farmacologia , Vitaminas/biossíntese
14.
J Am Soc Nephrol ; 28(4): 1106-1116, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27864430

RESUMO

People of African ancestry carrying certain APOL1 mutant alleles are at elevated risk of developing renal diseases. However, the mechanisms underlying APOL1-associated renal diseases are unknown. Because the APOL1 gene is unique to humans and some primates, new animal models are needed to understand the function of APOL1 in vivo We generated transgenic Drosophila fly lines expressing the human APOL1 wild type allele (G0) or the predominant APOL1 risk allele (G1) in different tissues. Ubiquitous expression of APOL1 G0 or G1 in Drosophila induced lethal phenotypes, and G1 was more toxic than was G0. Selective expression of the APOL1 G0 or G1 transgene in nephrocytes, fly cells homologous to mammalian podocytes, induced increased endocytic activity and accumulation of hemolymph proteins, dextran particles, and silver nitrate. As transgenic flies with either allele aged, nephrocyte function declined, cell size increased, and nephrocytes died prematurely. Compared with G0-expressing cells, however, G1-expressing cells showed more dramatic phenotypes, resembling those observed in cultured mammalian podocytes overexpressing APOL1-G1. Expressing the G0 or G1 APOL1 transgene in nephrocytes also impaired the acidification of organelles. We conclude that expression of an APOL1 transgene initially enhances nephrocyte function, causing hypertrophy and subsequent cell death. This new Drosophila model uncovers a novel mechanism by which upregulated expression of APOL1-G1 could precipitate renal disease in humans. Furthermore, this model may facilitate the identification of APOL1-interacting molecules that could serve as new drug targets to treat APOL1-associated renal diseases.


Assuntos
Apolipoproteínas/genética , Morte Celular/fisiologia , Nefropatias/genética , Rim/patologia , Lipoproteínas HDL/genética , Alelos , Animais , Animais Geneticamente Modificados , Apolipoproteína L1 , Células Cultivadas , Modelos Animais de Doenças , Progressão da Doença , Drosophila , Regulação da Expressão Gênica , Humanos , Hipertrofia/genética , Nefropatias/patologia
15.
Dev Biol ; 413(2): 188-98, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26994311

RESUMO

The Drosophila ostia are valve-like structures in the heart with functional similarity to vertebrate cardiac valves. The Wnt/ß-catenin signaling pathway is critical for valve development in zebrafish and mouse, but the key ligand(s) for valve induction remains unclear. We observed high levels of Wnt4 gene expression in Drosophila ostia progenitor cells, immediately prior to morphological differentiation of these cells associated with ostia formation. This differentiation was blocked in Wnt4 mutants and in flies expressing canonical Wnt signaling pathway inhibitors but not inhibitors of the planar cell polarity pathway. High levels of Wnt4 dependent activation of a canonical Wnt signaling reporter was observed specifically in ostia progenitor cells. In vertebrate valve formation Wnt signaling is active in cells undergoing early endothelial-mesenchymal transition (EMT) and the Wnt9 homolog of Drosophila Wnt4 is expressed in valve progenitors. In demonstrating an essential role for Wnt4 in ostia development we have identified similarities between molecular and cellular events associated with early EMT during vertebrate valve development and the differentiation and partial delamination of ostia progenitor cells in the process of ostia formation.


Assuntos
Proteínas de Drosophila/fisiologia , Drosophila/embriologia , Glicoproteínas/fisiologia , Proteínas Wnt/fisiologia , Animais , Coração/embriologia , Morfogênese , Transdução de Sinais , Células-Tronco/citologia
16.
Cell Tissue Res ; 368(3): 615-627, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28180992

RESUMO

The Drosophila nephrocyte is a critical component of the fly renal system and bears structural and functional homology to podocytes and proximal tubule cells of the mammalian kidney. Investigations of nephrocyte cell biological processes are fundamental to understanding the insect renal system. Nephrocytes are highly active in endocytosis and vesicle trafficking. Rab GTPases regulate endocytosis and trafficking but specific functions of nephrocyte Rabs remain undefined. We analyzed Rab GTPase expression and function in Drosophila nephrocytes and found that 11 out of 27 Drosophila Rabs were required for normal activity. Rabs 1, 5, 7, 11 and 35 were most important. Gene silencing of the nephrocyte-specific Rab5 eliminated all intracellular vesicles and the specialized plasma membrane structures essential for nephrocyte function. Rab7 silencing dramatically increased clear vacuoles and reduced lysosomes. Rab11 silencing increased lysosomes and reduced clear vacuoles. Our results suggest that Rab5 mediates endocytosis that is essential for the maintenance of functionally critical nephrocyte plasma membrane structures and that Rabs 7 and 11 mediate alternative downstream vesicle trafficking pathways leading to protein degradation and membrane recycling, respectively. Elucidating molecular pathways underlying nephrocyte function has the potential to yield important insights into human kidney cell physiology and mechanisms of cell injury that lead to disease. The Drosophila nephrocyte is emerging as a useful in vivo model system for molecular target identification and initial testing of therapeutic approaches in humans.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila/enzimologia , Proteínas rab de Ligação ao GTP/metabolismo , Animais , Tamanho Celular , Vesículas Citoplasmáticas , Drosophila/citologia , Drosophila/ultraestrutura , Feminino , Inativação Gênica , Rim/citologia , Rim/enzimologia , Rim/ultraestrutura , Lisossomos/enzimologia , Masculino , Podócitos/enzimologia , Podócitos/ultraestrutura , Proteínas rab de Ligação ao GTP/genética
17.
J Biol Chem ; 289(47): 32469-80, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25296752

RESUMO

Vision requires the generation of cone and rod photoreceptors that function in daylight and dim light, respectively. The neural retina leucine zipper factor (NRL) transcription factor critically controls photoreceptor fates as it stimulates rod differentiation and suppresses cone differentiation. However, the controls over NRL induction that balance rod and cone fates remain unclear. We have reported previously that the retinoid-related orphan receptor ß gene (Rorb) is required for Nrl expression and other retinal functions. We show that Rorb differentially expresses two isoforms: RORß2 in photoreceptors and RORß1 in photoreceptors, progenitor cells, and other cell types. Deletion of RORß2 or RORß1 increased the cone:rod ratio ∼2-fold, whereas deletion of both isoforms in Rorb(-/-) mice produced almost exclusively cone-like cells at the expense of rods, suggesting that both isoforms induce Nrl. Electroporation of either RORß isoform into retinal explants from Rorb(-/-) neonates reactivated Nrl and rod genes but, in Nrl(-/-) explants, failed to reactivate rod genes, indicating that NRL is the effector for both RORß isoforms in rod differentiation. Unexpectedly, RORß2 expression was lost in Nrl(-/-) mice. Moreover, NRL activated the RORß2-specific promoter of Rorb, indicating that NRL activates Rorb, its own inducer gene. We suggest that feedback activation between Nrl and Rorb genes reinforces the commitment to rod differentiation.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Proteínas do Olho/metabolismo , Membro 2 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Células Fotorreceptoras de Vertebrados/metabolismo , Animais , Animais Recém-Nascidos , Fatores de Transcrição de Zíper de Leucina Básica/genética , Western Blotting , Diferenciação Celular/genética , Proteínas do Olho/genética , Retroalimentação Fisiológica , Regulação da Expressão Gênica no Desenvolvimento , Hibridização In Situ , Camundongos Knockout , Microscopia Confocal , Membro 2 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Opsinas/genética , Opsinas/metabolismo , Regiões Promotoras Genéticas/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Retina/embriologia , Retina/metabolismo , Células Fotorreceptoras Retinianas Cones/metabolismo , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Heliyon ; 10(18): e37759, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39315153

RESUMO

Since the dawn of the industrial era, the relationship between human well-being and technological in-novation has become increasingly close. This study explores this intricate relationship to understand how technological advancements can be harnessed to promote sustained and improved well-being for all. Focusing on China as a case study, this study considers both human well-being and technological innovation as key research objects. An evaluation index system for well-being is established by leveraging the spatial Durbin model and existing literature. This study empirically calculates well-being levels and conducts a classification analysis of the coupling and coordination between well-being and technological innovation across 31 provinces and cities. Additionally, the factors driving the coupling and coordination relationships are further clarified. The results reveal that (1) the coordination between well-being and technological innovation varies significantly between provinces but, overall, is gradually increasing; (2) a significant positive correlation exists between well-being and the coupling and coordination of scientific and technological innovation, and the spatial aggregation of the coupling and coordination development is gradually strengthening; and (3) several key factors influence this relationship. Rationalisation of the industrial structure, inclusive digital finance, talent concentration, and consumption rate all yield positive and significant impacts. Conversely, government intervention appears to negatively influence the coordination between these two crucial aspects. Based on this study's results, a series of policy recommendations are proposed to coordinate the development of well-being and technological innovation.

19.
Environ Int ; 186: 108574, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38507933

RESUMO

The emergence of antibiotic-resistant bacteria poses a huge threat to the treatment of infections. Antimicrobial peptides are a class of short peptides that widely exist in organisms and are considered as potential substitutes for traditional antibiotics. Here, we use metagenomics combined with machine learning to find antimicrobial peptides from environmental metagenomes and successfully obtained 16,044,909 predicted AMPs. We compared the abundance of potential antimicrobial peptides in natural environments and engineered environments, and found that engineered environments also have great potential. Further, we chose sludge as a typical engineered environmental sample, and tried to mine antimicrobial peptides from it. Through metaproteome analysis and correlation analysis, we mined 27 candidate AMPs from sludge. We successfully synthesized 25 peptides by chemical synthesis, and experimentally verified that 21 peptides had antibacterial activity against the 4 strains tested. Our work highlights the potential for mining new antimicrobial peptides from engineered environments and demonstrates the effectiveness of mining antimicrobial peptides from sludge.


Assuntos
Peptídeos Antimicrobianos , Aprendizado de Máquina , Metagenoma , Esgotos , Esgotos/microbiologia , Peptídeos Antimicrobianos/farmacologia , Metagenômica , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos
20.
J Hazard Mater ; 477: 135409, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39096636

RESUMO

Antibiotic-resistant bacteria (ARBs) have been widely detected in wastewater and become a potential threat to human health. This work found that low-load single-atom copper (0.1 wt%) anchored on g-C3N4 (SA-Cu/g-C3N4) exhibited excellent ability to activate H2O2 and inactivate ARBs during the photo-Fenton process. The presence of SA-Cu/g-C3N4 (0.4 mg/mL) and H2O2 (0.1 mM) effectively inactivated ARBs. More than 99.9999 % (6-log) of methicillin-resistant Staphylococcus aureus (MRSA), and carbapenem-resistant Acinetobacter baumannii (CRAB) could be inactivated within 5 min. Extended-spectrum ß-lactamase-producing pathogenic Escherichia coli (ESBL-E) and vancomycin-resistant Enterococcus faecium (VRE) were killed within 10 and 30 min, respectively. In addition, more than 5-log of these ARBs were killed within 60 min in real wastewater. Furthermore, D2O-labeling with Raman spectroscopy revealed that SA-Cu/g-C3N4 completely suppressed the viable but nonculturable (VBNC) state and reactivation of bacteria. Electron paramagnetic resonance spectroscopy results demonstrated that g-C3N4 mainly produced 1O2, while SA-Cu/g-C3N4 simultaneously produced both 1O2 and •OH. The •OH and 1O2 cause lipid peroxidation damage to the cell membrane, resulting in the death of the bacteria. These findings highlight that the SA-Cu/g-C3N4 catalyst is a promising photo-Fenton catalyst for the inactivation of ARBs in wastewater.


Assuntos
Acinetobacter baumannii , Antibacterianos , Cobre , Peróxido de Hidrogênio , Águas Residuárias , Cobre/química , Cobre/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Catálise , Acinetobacter baumannii/efeitos dos fármacos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/farmacologia , Águas Residuárias/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos
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