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1.
Immunity ; 54(1): 151-163.e6, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33220232

RESUMO

The gastrointestinal tract is known as the largest endocrine organ that encounters and integrates various immune stimulations and neuronal responses due to constant environmental challenges. Enterochromaffin (EC) cells, which function as chemosensors on the gut epithelium, are known to translate environmental cues into serotonin (5-HT) production, contributing to intestinal physiology. However, how immune signals participate in gut sensation and neuroendocrine response remains unclear. Interleukin-33 (IL-33) acts as an alarmin cytokine by alerting the system of potential environmental stresses. We here demonstrate that IL-33 induced instantaneous peristaltic movement and facilitated Trichuris muris expulsion. We found that IL-33 could be sensed by EC cells, inducing release of 5-HT. IL-33-mediated 5-HT release activated enteric neurons, subsequently promoting gut motility. Mechanistically, IL-33 triggered calcium influx via a non-canonical signaling pathway specifically in EC cells to induce 5-HT secretion. Our data establish an immune-neuroendocrine axis in calibrating rapid 5-HT release for intestinal homeostasis.


Assuntos
Células Enterocromafins/fisiologia , Interleucina-33/metabolismo , Intestinos/fisiologia , Neurônios/fisiologia , Serotonina/metabolismo , Tricuríase/imunologia , Trichuris/fisiologia , Animais , Sinalização do Cálcio , Homeostase , Interleucina-33/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neuroimunomodulação , Peristaltismo
2.
Nature ; 634(8034): 617-625, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39232174

RESUMO

The adoption of agriculture triggered a rapid shift towards starch-rich diets in human populations1. Amylase genes facilitate starch digestion, and increased amylase copy number has been observed in some modern human populations with high-starch intake2, although evidence of recent selection is lacking3,4. Here, using 94 long-read haplotype-resolved assemblies and short-read data from approximately 5,600 contemporary and ancient humans, we resolve the diversity and evolutionary history of structural variation at the amylase locus. We find that amylase genes have higher copy numbers in agricultural populations than in fishing, hunting and pastoral populations. We identify 28 distinct amylase structural architectures and demonstrate that nearly identical structures have arisen recurrently on different haplotype backgrounds throughout recent human history. AMY1 and AMY2A genes each underwent multiple duplication/deletion events with mutation rates up to more than 10,000-fold the single-nucleotide polymorphism mutation rate, whereas AMY2B gene duplications share a single origin. Using a pangenome-based approach, we infer structural haplotypes across thousands of humans identifying extensively duplicated haplotypes at higher frequency in modern agricultural populations. Leveraging 533 ancient human genomes, we find that duplication-containing haplotypes (with more gene copies than the ancestral haplotype) have rapidly increased in frequency over the past 12,000 years in West Eurasians, suggestive of positive selection. Together, our study highlights the potential effects of the agricultural revolution on human genomes and the importance of structural variation in human adaptation.


Assuntos
Agricultura , Amilases , Evolução Molecular , Dosagem de Genes , Genoma Humano , Haplótipos , Seleção Genética , Humanos , Agricultura/história , Agricultura/estatística & dados numéricos , Amilases/genética , Amilases/química , Dosagem de Genes/genética , Duplicação Gênica/genética , Loci Gênicos/genética , Genoma Humano/genética , Haplótipos/genética , História Antiga , Taxa de Mutação , Polimorfismo de Nucleotídeo Único/genética , Caça/estatística & dados numéricos , Deleção de Genes , DNA Antigo/análise
3.
Nature ; 630(8016): 401-411, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38811727

RESUMO

Apes possess two sex chromosomes-the male-specific Y chromosome and the X chromosome, which is present in both males and females. The Y chromosome is crucial for male reproduction, with deletions being linked to infertility1. The X chromosome is vital for reproduction and cognition2. Variation in mating patterns and brain function among apes suggests corresponding differences in their sex chromosomes. However, owing to their repetitive nature and incomplete reference assemblies, ape sex chromosomes have been challenging to study. Here, using the methodology developed for the telomere-to-telomere (T2T) human genome, we produced gapless assemblies of the X and Y chromosomes for five great apes (bonobo (Pan paniscus), chimpanzee (Pan troglodytes), western lowland gorilla (Gorilla gorilla gorilla), Bornean orangutan (Pongo pygmaeus) and Sumatran orangutan (Pongo abelii)) and a lesser ape (the siamang gibbon (Symphalangus syndactylus)), and untangled the intricacies of their evolution. Compared with the X chromosomes, the ape Y chromosomes vary greatly in size and have low alignability and high levels of structural rearrangements-owing to the accumulation of lineage-specific ampliconic regions, palindromes, transposable elements and satellites. Many Y chromosome genes expand in multi-copy families and some evolve under purifying selection. Thus, the Y chromosome exhibits dynamic evolution, whereas the X chromosome is more stable. Mapping short-read sequencing data to these assemblies revealed diversity and selection patterns on sex chromosomes of more than 100 individual great apes. These reference assemblies are expected to inform human evolution and conservation genetics of non-human apes, all of which are endangered species.


Assuntos
Hominidae , Cromossomo X , Cromossomo Y , Animais , Feminino , Masculino , Gorilla gorilla/genética , Hominidae/genética , Hominidae/classificação , Hylobatidae/genética , Pan paniscus/genética , Pan troglodytes/genética , Filogenia , Pongo abelii/genética , Pongo pygmaeus/genética , Telômero/genética , Cromossomo X/genética , Cromossomo Y/genética , Evolução Molecular , Variações do Número de Cópias de DNA/genética , Humanos , Espécies em Perigo de Extinção , Padrões de Referência
4.
Nature ; 621(7978): 344-354, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37612512

RESUMO

The human Y chromosome has been notoriously difficult to sequence and assemble because of its complex repeat structure that includes long palindromes, tandem repeats and segmental duplications1-3. As a result, more than half of the Y chromosome is missing from the GRCh38 reference sequence and it remains the last human chromosome to be finished4,5. Here, the Telomere-to-Telomere (T2T) consortium presents the complete 62,460,029-base-pair sequence of a human Y chromosome from the HG002 genome (T2T-Y) that corrects multiple errors in GRCh38-Y and adds over 30 million base pairs of sequence to the reference, showing the complete ampliconic structures of gene families TSPY, DAZ and RBMY; 41 additional protein-coding genes, mostly from the TSPY family; and an alternating pattern of human satellite 1 and 3 blocks in the heterochromatic Yq12 region. We have combined T2T-Y with a previous assembly of the CHM13 genome4 and mapped available population variation, clinical variants and functional genomics data to produce a complete and comprehensive reference sequence for all 24 human chromosomes.


Assuntos
Cromossomos Humanos Y , Genômica , Análise de Sequência de DNA , Humanos , Sequência de Bases , Cromossomos Humanos Y/genética , DNA Satélite/genética , Variação Genética/genética , Genética Populacional , Genômica/métodos , Genômica/normas , Heterocromatina/genética , Família Multigênica/genética , Padrões de Referência , Duplicações Segmentares Genômicas/genética , Análise de Sequência de DNA/normas , Sequências de Repetição em Tandem/genética , Telômero/genética
5.
Nature ; 611(7936): 519-531, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36261518

RESUMO

The current human reference genome, GRCh38, represents over 20 years of effort to generate a high-quality assembly, which has benefitted society1,2. However, it still has many gaps and errors, and does not represent a biological genome as it is a blend of multiple individuals3,4. Recently, a high-quality telomere-to-telomere reference, CHM13, was generated with the latest long-read technologies, but it was derived from a hydatidiform mole cell line with a nearly homozygous genome5. To address these limitations, the Human Pangenome Reference Consortium formed with the goal of creating high-quality, cost-effective, diploid genome assemblies for a pangenome reference that represents human genetic diversity6. Here, in our first scientific report, we determined which combination of current genome sequencing and assembly approaches yield the most complete and accurate diploid genome assembly with minimal manual curation. Approaches that used highly accurate long reads and parent-child data with graph-based haplotype phasing during assembly outperformed those that did not. Developing a combination of the top-performing methods, we generated our first high-quality diploid reference assembly, containing only approximately four gaps per chromosome on average, with most chromosomes within ±1% of the length of CHM13. Nearly 48% of protein-coding genes have non-synonymous amino acid changes between haplotypes, and centromeric regions showed the highest diversity. Our findings serve as a foundation for assembling near-complete diploid human genomes at scale for a pangenome reference to capture global genetic variation from single nucleotides to structural rearrangements.


Assuntos
Mapeamento Cromossômico , Diploide , Genoma Humano , Genômica , Humanos , Mapeamento Cromossômico/normas , Genoma Humano/genética , Haplótipos/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Sequenciamento de Nucleotídeos em Larga Escala/normas , Análise de Sequência de DNA/métodos , Análise de Sequência de DNA/normas , Padrões de Referência , Genômica/métodos , Genômica/normas , Cromossomos Humanos/genética , Variação Genética/genética
6.
EMBO J ; 42(19): e113639, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37565504

RESUMO

WRKY transcription factors in plants are known to be able to mediate either transcriptional activation or repression, but the mechanism regulating their transcriptional activity is largely unclear. We found that group IId WRKY transcription factors interact with OBERON (OBE) proteins, forming redundant WRKY-OBE complexes in Arabidopsis thaliana. The coiled-coil domain of WRKY transcription factors binds to OBE proteins and is responsible for target gene selection and transcriptional repression. The PHD finger of OBE proteins binds to both histones and WRKY transcription factors. WRKY-OBE complexes repress the transcription of numerous stress-responsive genes and are required for maintaining normal plant growth. Several WRKY and OBE mutants show reduced plant size and increased drought tolerance, accompanied by increased expression of stress-responsive genes. Moreover, expression levels of most of these WRKY and OBE genes are reduced in response to drought stress, revealing a previously uncharacterized regulatory mechanism of the drought stress response. These results suggest that WRKY-OBE complexes repress transcription of stress-responsive genes, and thereby balance plant growth and stress tolerance.


Assuntos
Arabidopsis , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Histonas/genética , Histonas/metabolismo , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas , Filogenia
7.
Proc Natl Acad Sci U S A ; 121(8): e2317796121, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38346201

RESUMO

Tremendous attention has been paid to the water-associated side reactions and zinc (Zn) dendrite growth on the electrode-electrolyte interface. However, the Zn pulverization that can cause continuous depletion of active Zn metal and exacerbate hydrogen evolution is severely neglected. Here, we disclose that the excessive Zn feeding that causes incomplete crystallization is responsible for Zn pulverization formation through analyzing the thermodynamic and kinetics process of Zn deposition. On the basis, we introduce 1-ethyl-3-methylimidazolium cations (EMIm+) into the electrolyte to form a Galton-board-like three-dimensional inert-cation (3DIC) region. Modeling test shows that the 3DIC EMIm+ can induce the Zn2+ flux to follow in a Gauss distribution, thus acting as elastic sites to buffer the perpendicular diffusion of Zn2+ and direct the lateral diffusion, thus effectively avoiding the local Zn2+ accumulation and irreversible crystal formation. Consequently, anti-pulverized Zn metal deposition behavior is achieved with an average Coulombic efficiency of 99.6% at 5 mA cm-2 over 2,000 cycles and superb stability in symmetric cell over 1,200 h at -30 °C. Furthermore, the Zn||KVOH pouch cell can stably cycle over 1,200 cycles at 2 A g-1 and maintain a capacity of up to 12 mAh.

8.
EMBO J ; 41(6): e108650, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35156721

RESUMO

Gene expression is tightly regulated at the levels of both mRNA translation and stability. The poly(A)-binding protein (PABP) is thought to play a role in regulating these processes by binding the mRNA 3' poly(A) tail and interacting with both the translation and mRNA deadenylation machineries. In this study, we directly investigate the impact of PABP on translation and stability of endogenous mRNAs in human cells. Remarkably, our transcriptome-wide analysis only detects marginal mRNA translation changes in PABP-depleted cells. In contrast, rapidly depleting PABP alters mRNA abundance and stability, albeit non-uniformly. Otherwise stable transcripts, including those encoding proteins with constitutive functions, are destabilized in PABP-depleted cells. In contrast, many unstable mRNAs, including those encoding proteins with regulatory functions, decay at similar rates in presence or absence of PABP. Moreover, PABP depletion-induced cell death can partially be suppressed by disrupting the mRNA decapping and 5'-3' decay machinery. Finally, we provide evidence that the LSM1-7 complex promotes decay of "stable" mRNAs in PABP-depleted cells. Taken together, these findings suggest that PABP plays an important role in preventing the untimely decay of select mRNA populations.


Assuntos
Perfilação da Expressão Gênica , Morte Celular , Humanos , RNA Mensageiro/genética
9.
Nat Methods ; 20(8): 1213-1221, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37365340

RESUMO

Advancements in sequencing technologies and assembly methods enable the regular production of high-quality genome assemblies characterizing complex regions. However, challenges remain in efficiently interpreting variation at various scales, from smaller tandem repeats to megabase rearrangements, across many human genomes. We present a PanGenome Research Tool Kit (PGR-TK) enabling analyses of complex pangenome structural and haplotype variation at multiple scales. We apply the graph decomposition methods in PGR-TK to the class II major histocompatibility complex demonstrating the importance of the human pangenome for analyzing complicated regions. Moreover, we investigate the Y-chromosome genes, DAZ1/DAZ2/DAZ3/DAZ4, of which structural variants have been linked to male infertility, and X-chromosome genes OPN1LW and OPN1MW linked to eye disorders. We further showcase PGR-TK across 395 complex repetitive medically important genes. This highlights the power of PGR-TK to resolve complex variation in regions of the genome that were previously too complex to analyze.


Assuntos
Genoma Humano , Genômica , Masculino , Humanos , Complexo Principal de Histocompatibilidade
10.
Proc Natl Acad Sci U S A ; 120(14): e2219043120, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-36996112

RESUMO

Despite the various strategies for achieving metal-nitrogen-carbon (M-N-C) single-atom catalysts (SACs) with different microenvironments for electrochemical carbon dioxide reduction reaction (CO2RR), the synthesis-structure-performance correlation remains elusive due to the lack of well-controlled synthetic approaches. Here, we employed Ni nanoparticles as starting materials for the direct synthesis of nickel (Ni) SACs in one spot through harvesting the interaction between metallic Ni and N atoms in the precursor during the chemical vapor deposition growth of hierarchical N-doped graphene fibers. By combining with first-principle calculations, we found that the Ni-N configuration is closely correlated to the N contents in the precursor, in which the acetonitrile with a high N/C ratio favors the formation of Ni-N3, while the pyridine with a low N/C ratio is more likely to promote the evolution of Ni-N2. Moreover, we revealed that the presence of N favors the formation of H-terminated edge of sp2 carbon and consequently leads to the formation of graphene fibers consisting of vertically stacked graphene flakes, instead of the traditional growth of carbon nanotubes on Ni nanoparticles. With a high capability in balancing the *COOH formation and *CO desorption, the as-prepared hierarchical N-doped graphene nanofibers with Ni-N3 sites exhibit a superior CO2RR performance compared to that with Ni-N2 and Ni-N4 ones.

11.
J Immunol ; 210(10): 1494-1507, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37010945

RESUMO

IFN-stimulated genes (ISGs) can act as effector molecules against viral infection and can also regulate pathogenic infection and host immune response. N-Myc and STAT interactor (Nmi) is reported as an ISG in mammals and in fish. In this study, the expression of Nmi was found to be induced significantly by the infection of Siniperca chuatsi rhabdovirus (SCRV), and the induced expression of type I IFNs after SCRV infection was reduced following Nmi overexpression. It is observed that Nmi can interact with IRF3 and IRF7 and promote the autophagy-mediated degradation of these two transcription factors. Furthermore, Nmi was found to be interactive with IFP35 through the CC region to inhibit IFP35 protein degradation, thereby enhancing the negative role in type I IFN expression after viral infection. In turn, IFP35 is also capable of protecting Nmi protein from degradation through its N-terminal domain. It is considered that Nmi and IFP35 in fish can also interact with each other in regulating negatively the expression of type I IFNs, but thus in enhancing the replication of SCRV.


Assuntos
Interferon Tipo I , Peptídeos e Proteínas de Sinalização Intracelular , Animais , Interferon Tipo I/metabolismo , Peixes
12.
J Immunol ; 210(11): 1771-1789, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37017564

RESUMO

The type IV IFN (IFN-υ) is reported in vertebrates from fish to primary mammals with IFN-υR1 and IL-10R2 as receptor subunits. In this study, the proximal promoter of IFN-υ was identified in the amphibian model, Xenopus laevis, with functional IFN-sensitive responsive element and NF-κB sites, which can be transcriptionally activated by transcription factors, such as IFN regulatory factor (IRF)1, IRF3, IRF7, and p65. It was further found that IFN-υ signals through the classical IFN-stimulated gene (ISG) factor 3 (ISGF3) to induce the expression of ISGs. It seems likely that the promoter elements of the IFN-υ gene in amphibians is similar to type III IFN genes, and that the mechanism involved in IFN-υ induction is very much similar to type I and III IFNs. Using recombinant IFN-υ protein and the X. laevis A6 cell line, >400 ISGs were identified in the transcriptome, including ISGs homologous to humans. However, as many as 268 genes were unrelated to human or zebrafish ISGs, and some of these ISGs were expanded families such as the amphibian novel TRIM protein (AMNTR) family. AMNTR50, a member in the family, was found to be induced by type I, III, and IV IFNs through IFN-sensitive responsive element sites of the proximal promoter, and this molecule has a negative role in regulating the expression of type I, III, and IV IFNs. It is considered that the current study contributes to the understanding of transcription, signaling, and functional aspects of type IV IFN at least in amphibians.


Assuntos
Interferon Tipo I , Interferons , Animais , Humanos , Xenopus laevis , Interferons/genética , Interferons/metabolismo , Peixe-Zebra/metabolismo , Regulação da Expressão Gênica , Transdução de Sinais , Interferon Tipo I/metabolismo , Mamíferos/metabolismo
13.
Proc Natl Acad Sci U S A ; 119(40): e2206990119, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36161913

RESUMO

Rapid detection of pathogenic bacteria within a few minutes is the key to control infectious disease. However, rapid detection of pathogenic bacteria in clinical samples is quite a challenging task due to the complex matrix, as well as the low abundance of bacteria in real samples. Herein, we employ a label-free single-particle imaging approach to address this challenge. By tracking the scattering intensity variation of single particles in free solution, the morphological heterogeneity can be well identified with particle size smaller than the diffraction limit, facilitating the morphological identification of single bacteria from a complex matrix in a label-free manner. Furthermore, the manipulation of convection in free solution enables the rapid screening of low-abundance bacteria in a small field of view, which significantly improves the sensitivity of single-particle detection. As a proof of concept demonstration, we are able to differentiate the group B streptococci (GBS)-positive samples within 10 min from vaginal swabs without using any biological reagents. This is the most rapid and low-cost method to the best of our knowledge. We believe that such a single-particle imaging approach will find wider applications in clinical diagnosis and disease control due to its high sensitivity, rapidity, simplicity, and low cost.


Assuntos
Bactérias , Doenças Transmissíveis , Análise de Célula Única , Bactérias/isolamento & purificação , Bactérias/patogenicidade , Doenças Transmissíveis/diagnóstico por imagem , Feminino , Humanos , Tamanho da Partícula , Análise de Célula Única/métodos , Esfregaço Vaginal
14.
Eur Heart J ; 45(9): 669-684, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38085922

RESUMO

BACKGROUND AND AIMS: Survivors of acute coronary syndromes face an elevated risk of recurrent atherosclerosis-related vascular events despite advanced medical treatments. The underlying causes remain unclear. This study aims to investigate whether myocardial infarction (MI)-induced trained immunity in monocytes could sustain proatherogenic traits and expedite atherosclerosis. METHODS: Apolipoprotein-E deficient (ApoE-/-) mice and adoptive bone marrow transfer chimeric mice underwent MI or myocardial ischaemia-reperfusion (IR). A subsequent 12-week high-fat diet (HFD) regimen was implemented to elucidate the mechanism behind monocyte trained immunity. In addition, classical monocytes were analysed by flow cytometry in the blood of enrolled patients. RESULTS: In MI and IR mice, blood monocytes and bone marrow-derived macrophages exhibited elevated spleen tyrosine kinase (SYK), lysine methyltransferase 5A (KMT5A), and CCHC-type zinc finger nucleic acid-binding protein (CNBP) expression upon exposure to a HFD or oxidized LDL (oxLDL) stimulation. MI-induced trained immunity was transmissible by transplantation of bone marrow to accelerate atherosclerosis in naive recipients. KMT5A specifically recruited monomethylation of Lys20 of histone H4 (H4K20me) to the gene body of SYK and synergistically transactivated SYK with CNBP. In vivo small interfering RNA (siRNA) inhibition of KMT5A or CNBP potentially slowed post-MI atherosclerosis. Sympathetic denervation with 6-hydroxydopamine reduced atherosclerosis and inflammation after MI. Classical monocytes from ST-elevation MI (STEMI) patients with advanced coronary lesions expressed higher SYK and KMT5A gene levels. CONCLUSIONS: The findings underscore the crucial role of monocyte trained immunity in accelerated atherosclerosis after MI, implying that SYK in blood classical monocytes may serve as a predictive factor for the progression of atherosclerosis in STEMI patients.


Assuntos
Aterosclerose , Infarto do Miocárdio , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Animais , Camundongos , Monócitos , Imunidade Treinada
15.
Hum Mol Genet ; 31(8): 1325-1335, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-34740257

RESUMO

Type V collagen is a regulatory fibrillar collagen essential for type I collagen fibril nucleation and organization and its deficiency leads to structurally abnormal extracellular matrix (ECM). Haploinsufficiency of the Col5a1 gene encoding α(1) chain of type V collagen is the primary cause of classic Ehlers-Danlos syndrome (EDS). The mechanisms by which this initial insult leads to the spectrum of clinical presentation are not fully understood. Using transcriptome analysis of skin and Achilles tendons from Col5a1 haploinsufficient (Col5a1+/-) mice, we recognized molecular alterations associated with the tissue phenotypes. We identified dysregulation of ECM components including thrombospondin-1, lysyl oxidase, and lumican in the skin of Col5a1+/- mice when compared with control. We also identified upregulation of transforming growth factor ß1 (Tgf-ß) in serum and increased expression of pSmad2 in skin from Col5a1+/- mice, suggesting Tgf-ß dysregulation is a contributor to abnormal wound healing and atrophic scarring seen in classic EDS. Together, these findings support altered matrix to cell signaling as a component of the pathogenesis of the tissue phenotype in classic EDS and point out potential downstream signaling pathways that may be targeted for the treatment of this disease.


Assuntos
Síndrome de Ehlers-Danlos , Animais , Colágeno/genética , Colágeno Tipo V/genética , Modelos Animais de Doenças , Síndrome de Ehlers-Danlos/genética , Síndrome de Ehlers-Danlos/patologia , Haploinsuficiência , Camundongos , Fator de Crescimento Transformador beta/genética
16.
Am J Hum Genet ; 108(9): 1710-1724, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34450031

RESUMO

Coatomer complexes function in the sorting and trafficking of proteins between subcellular organelles. Pathogenic variants in coatomer subunits or associated factors have been reported in multi-systemic disorders, i.e., coatopathies, that can affect the skeletal and central nervous systems. We have identified loss-of-function variants in COPB2, a component of the coatomer complex I (COPI), in individuals presenting with osteoporosis, fractures, and developmental delay of variable severity. Electron microscopy of COPB2-deficient subjects' fibroblasts showed dilated endoplasmic reticulum (ER) with granular material, prominent rough ER, and vacuoles, consistent with an intracellular trafficking defect. We studied the effect of COPB2 deficiency on collagen trafficking because of the critical role of collagen secretion in bone biology. COPB2 siRNA-treated fibroblasts showed delayed collagen secretion with retention of type I collagen in the ER and Golgi and altered distribution of Golgi markers. copb2-null zebrafish embryos showed retention of type II collagen, disorganization of the ER and Golgi, and early larval lethality. Copb2+/- mice exhibited low bone mass, and consistent with the findings in human cells and zebrafish, studies in Copb2+/- mouse fibroblasts suggest ER stress and a Golgi defect. Interestingly, ascorbic acid treatment partially rescued the zebrafish developmental phenotype and the cellular phenotype in Copb2+/- mouse fibroblasts. This work identifies a form of coatopathy due to COPB2 haploinsufficiency, explores a potential therapeutic approach for this disorder, and highlights the role of the COPI complex as a regulator of skeletal homeostasis.


Assuntos
Osso e Ossos/metabolismo , Complexo I de Proteína do Envoltório/genética , Proteína Coatomer/genética , Deficiências do Desenvolvimento/genética , Deficiência Intelectual/genética , Osteoporose/genética , Animais , Ácido Ascórbico/farmacologia , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Criança , Pré-Escolar , Complexo I de Proteína do Envoltório/deficiência , Proteína Coatomer/química , Proteína Coatomer/deficiência , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Deficiências do Desenvolvimento/diagnóstico por imagem , Deficiências do Desenvolvimento/metabolismo , Deficiências do Desenvolvimento/patologia , Embrião não Mamífero , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/patologia , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Regulação da Expressão Gênica no Desenvolvimento , Complexo de Golgi , Haploinsuficiência , Humanos , Deficiência Intelectual/diagnóstico por imagem , Deficiência Intelectual/metabolismo , Deficiência Intelectual/patologia , Masculino , Camundongos , Osteoporose/tratamento farmacológico , Osteoporose/metabolismo , Osteoporose/patologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Índice de Gravidade de Doença , Peixe-Zebra
17.
Anal Chem ; 96(29): 12074-12083, 2024 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-38981066

RESUMO

Activatable probes with a higher signal-to-background ratio and accuracy are essential for monitoring liver cancer as well as intraoperative fluorescence navigation. However, the presence of only one biomarker is usually not sufficient to meet the high requirement of a signal-to-background ratio in cancer surveillance, leading to the risk of misdiagnosis. In this work, a dual-locked activation response probe, Si-NTR-LAP, for nitroreductase and leucine aminopeptidase was reported. This dual-locked probe provides better tumor recognition and a higher signal-to-noise ratio than that of single-locked probes (Si-LAP and Si-NTR). In both the subcutaneous tumor model and the more complex orthotopic hepatocellular carcinoma model, the probe was able to identify tumor tissue with high specificity and accurately differentiate the boundaries between tumor tissue and normal tissue. Therefore, the dual-locked probe may provide a new and practical strategy for applying to real patient tumor tissue samples.


Assuntos
Leucil Aminopeptidase , Neoplasias Hepáticas , Nitrorredutases , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/metabolismo , Humanos , Animais , Leucil Aminopeptidase/metabolismo , Leucil Aminopeptidase/análise , Nitrorredutases/metabolismo , Nitrorredutases/análise , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/metabolismo , Camundongos , Corantes Fluorescentes/química , Imagem Óptica
18.
Small ; : e2403573, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39258373

RESUMO

Photocatalytic reforming (PR) of polyester waste, fueled by renewable sources like solar energy, offers a sustainable method for producing clean H2 and valuable by-products under mild conditions. The design of high-performance photocatalyst plays a pivotal role in determining the efficacy of an alkaline polyester PR system, influencing H2 generation activity and selectivity. Here, ultrathin porous carbon nitride nanosheets (UP-CN) loaded with Pt nanoclusters (Pt NCs, average diameter of 1.7 nm) with uniform Pt NCs distribution are introduced. The resulting Pt NCs/UP-CN catalyst can accelerate charge and mass transfer while providing additional active sites, achieving superior H2 generation rates of 11.69 mmol gcat -1 h-1 and 2923 mmol gPt -1 h-1 under AM 1.5 light, which nine times higher than that of Pt nanoparticles-bulk graphitic carbon nitride composite (1.29 mmol gcat -1 h-1 and 258 mmol gPt -1 h-1) as counterpart. This performance also surpasses that of previously reported carbon nitride-based and TiO2-based photocatalysts. Moreover, the density functional theory calculations reveal a significant reduction in the energy barrier for the water dissociation step (H2O + * → *H + OH) at the interface between UP-CN and anchored Pt NCs, showcasing the synergistic effect between Pt NCs and UP-CN. This catalytic system also exhibits universality across various polyester plastics.

19.
Small ; : e2406032, 2024 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-39449209

RESUMO

Mn-based metal halides scintillators with high photoluminescence quantum yield (PLQY) have recently emerged as promising large-size candidates for X-ray imaging but still remains as difficult challenge in stability and high processing temperatures. Here, three manganese halides are designed by introducing branched chains into organic cations and extending the carbon chains, namely (i-PrTPP)2MnBr4, (i-BuTPP)2MnBr4 and (i-AmTPP)2MnBr4, successfully lowered the melting point of manganese halides to 120.2 °C. Three materials show striking light yields of 59 000, 40 000, and 52 000 photons MeV-1, respectively. The lowest detection limits are 42.30, 50.92, and 45.71 nGy s-1, respectively. Meanwhile, compared to their counterparts with linear carbon chains, the introduction of branched chains has significantly enhanced the stability of the scintillators in the glass state. A transparent glass has been prepared using a melt-quenching method, which exhibited 80% transmittance at 400-700 nm. The glass is utilized for X-ray imaging, achieving a high spatial resolution up to 46.6 lp mm-1. This result provides a new approach to enhancing the performance of such scintillator materials.

20.
Hepatology ; 78(3): 847-862, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35993161

RESUMO

BACKGROUND AND AIMS: BFKB8488A is a bispecific antibody targeting fibroblast growth factor receptor 1c and Klothoß. This phase 1b study assessed safety, tolerability, pharmacokinetics, immunogenicity, and pharmacodynamics of BFKB8488A in patients with type 2 diabetes mellitus (T2DM) or NAFLD. APPROACH AND RESULTS: Patients were randomized to receive multiple doses of BFKB8488A at various dose levels and dosing intervals (weekly, every 2 weeks, or every 4 weeks) or placebo for 12 weeks. The primary outcome was the safety of BFKB8488A. Overall, 153 patients (T2DM: 91; NAFLD: 62) were enrolled and received at least one dose of treatment. Of these, 102 patients (62.7%) reported at least one adverse event (BFKB8488A: 83 [68.6%]; placebo: 19 [59.4%]). BFKB8488A exhibited nonlinear pharmacokinetics, with greater than dose-proportional increases in exposure. The treatment-emergent antidrug antibody incidence was 22.7%. Overall, trends in exposure-dependent increases in high-density lipoprotein (HDL) and decreases in triglyceride levels were observed. Decreases in alanine aminotransferase and aspartate aminotransferase were 0.7% and 9.2% for medium exposure and 7.3% and 11.2% for high-exposure tertiles, compared with increases of 7.5% and 17% in the placebo group, respectively, at Day 85. In patients with NAFLD, the mean decrease from baseline liver fat was 13.0%, 34.5%, and 49.0% in the low-, medium-, and high-exposure tertiles, respectively, compared with 0.1% with placebo at Day 85. CONCLUSIONS: BFKB8488A was adequately tolerated in patients with T2DM or NAFLD, leading to triglyceride reduction, HDL improvements, and trends in improvement in markers of liver health for both populations and marked liver fat reduction in patients with NAFLD. ( ClinicalTrials.gov : NCT03060538).


Assuntos
Diabetes Mellitus Tipo 2 , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/uso terapêutico , Método Duplo-Cego , Triglicerídeos , Lipídeos
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