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1.
Nature ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009005

RESUMO

Transmission spectroscopy has been a workhorse technique over the past two decades to constrain the physical and chemical properties of exoplanet atmospheres 1-5. One of its classical key assumptions is that the portion of the atmosphere it probes - the terminator region - is homogeneous. Several works in the past decade, however, have put this into question for highly irradiated, hot (Teq ≳ 1000 K) gas giant exoplanets both empirically 6-10 and via 3-dimensional modelling 11-17. While models predict clear differences between the evening (day-to-night) and morning (night-to-day) terminators, direct morning/evening transmission spectra in a wide wavelength range has not been reported for an exoplanet to date. Under the assumption of precise and accurate orbital parameters on WASP-39 b, here we report the detection of inhomogeneous terminators on the exoplanet WASP-39 b, which allows us to retrieve its morning and evening transmission spectra in the near-infrared (2 - 5 µm) using JWST. We observe larger transit depths in the evening which are, on average, 405±88 ppm larger than the morning ones, also having qualitatively larger features than the morning spectrum. The spectra are best explained by models in which the evening terminator is hotter than the morning terminator by 177 - 57 + 65 K with both terminators having C/O ratios consistent with solar. General circulation models (GCMs) predict temperature differences broadly consistent with the above value and point towards a cloudy morning terminator and a clearer evening terminator.

2.
Nature ; 626(8001): 979-983, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38232945

RESUMO

The recent inference of sulfur dioxide (SO2) in the atmosphere of the hot (approximately 1,100 K), Saturn-mass exoplanet WASP-39b from near-infrared JWST observations1-3 suggests that photochemistry is a key process in high-temperature exoplanet atmospheres4. This is because of the low (<1 ppb) abundance of SO2 under thermochemical equilibrium compared with that produced from the photochemistry of H2O and H2S (1-10 ppm)4-9. However, the SO2 inference was made from a single, small molecular feature in the transmission spectrum of WASP-39b at 4.05 µm and, therefore, the detection of other SO2 absorption bands at different wavelengths is needed to better constrain the SO2 abundance. Here we report the detection of SO2 spectral features at 7.7 and 8.5 µm in the 5-12-µm transmission spectrum of WASP-39b measured by the JWST Mid-Infrared Instrument (MIRI) Low Resolution Spectrometer (LRS)10. Our observations suggest an abundance of SO2 of 0.5-25 ppm (1σ range), consistent with previous findings4. As well as SO2, we find broad water-vapour absorption features, as well as an unexplained decrease in the transit depth at wavelengths longer than 10 µm. Fitting the spectrum with a grid of atmospheric forward models, we derive an atmospheric heavy-element content (metallicity) for WASP-39b of approximately 7.1-8.0 times solar and demonstrate that photochemistry shapes the spectra of WASP-39b across a broad wavelength range.

3.
Nature ; 615(7952): 468-471, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36890226

RESUMO

The animal phyla and their associated body plans originate from a singular burst of evolution occurring during the Cambrian period, over 500 million years ago1. The phylum Bryozoa, the colonial 'moss animals', have been the exception: convincing skeletons of this biomineralizing clade have been absent from Cambrian strata, in part because potential bryozoan fossils are difficult to distinguish from the modular skeletons of other animal and algal groups2,3. At present, the strongest candidate4 is the phosphatic microfossil Protomelission5. Here we describe exceptionally preserved non-mineralized anatomy in Protomelission-like macrofossils from the Xiaoshiba Lagerstätte6. Taken alongside the detailed skeletal construction and the potential taphonomic origin of 'zooid apertures', we consider that Protomelission is better interpreted as the earliest dasycladalean green alga-emphasizing the ecological role of benthic photosynthesizers in early Cambrian communities. Under this interpretation, Protomelission cannot inform the origins of the bryozoan body plan; despite a growing number of promising candidates7-9, there remain no unequivocal bryozoans of Cambrian age.


Assuntos
Briozoários , Clorófitas , Fósseis , Filogenia , Animais , Briozoários/anatomia & histologia , Briozoários/classificação , Fosfatos/metabolismo , Clorófitas/anatomia & histologia , Clorófitas/classificação , Fotossíntese , China
4.
Nature ; 617(7961): 483-487, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37100917

RESUMO

Photochemistry is a fundamental process of planetary atmospheres that regulates the atmospheric composition and stability1. However, no unambiguous photochemical products have been detected in exoplanet atmospheres so far. Recent observations from the JWST Transiting Exoplanet Community Early Release Science Program2,3 found a spectral absorption feature at 4.05 µm arising from sulfur dioxide (SO2) in the atmosphere of WASP-39b. WASP-39b is a 1.27-Jupiter-radii, Saturn-mass (0.28 MJ) gas giant exoplanet orbiting a Sun-like star with an equilibrium temperature of around 1,100 K (ref. 4). The most plausible way of generating SO2 in such an atmosphere is through photochemical processes5,6. Here we show that the SO2 distribution computed by a suite of photochemical models robustly explains the 4.05-µm spectral feature identified by JWST transmission observations7 with NIRSpec PRISM (2.7σ)8 and G395H (4.5σ)9. SO2 is produced by successive oxidation of sulfur radicals freed when hydrogen sulfide (H2S) is destroyed. The sensitivity of the SO2 feature to the enrichment of the atmosphere by heavy elements (metallicity) suggests that it can be used as a tracer of atmospheric properties, with WASP-39b exhibiting an inferred metallicity of about 10× solar. We further point out that SO2 also shows observable features at ultraviolet and thermal infrared wavelengths not available from the existing observations.

5.
Nature ; 620(7973): 292-298, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37257843

RESUMO

Close-in giant exoplanets with temperatures greater than 2,000 K ('ultra-hot Jupiters') have been the subject of extensive efforts to determine their atmospheric properties using thermal emission measurements from the Hubble Space Telescope (HST) and Spitzer Space Telescope1-3. However, previous studies have yielded inconsistent results because the small sizes of the spectral features and the limited information content of the data resulted in high sensitivity to the varying assumptions made in the treatment of instrument systematics and the atmospheric retrieval analysis3-12. Here we present a dayside thermal emission spectrum of the ultra-hot Jupiter WASP-18b obtained with the NIRISS13 instrument on the JWST. The data span 0.85 to 2.85 µm in wavelength at an average resolving power of 400 and exhibit minimal systematics. The spectrum shows three water emission features (at >6σ confidence) and evidence for optical opacity, possibly attributable to H-, TiO and VO (combined significance of 3.8σ). Models that fit the data require a thermal inversion, molecular dissociation as predicted by chemical equilibrium, a solar heavy-element abundance ('metallicity', [Formula: see text] times solar) and a carbon-to-oxygen (C/O) ratio less than unity. The data also yield a dayside brightness temperature map, which shows a peak in temperature near the substellar point that decreases steeply and symmetrically with longitude towards the terminators.

6.
Nature ; 605(7908): 152-159, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35477759

RESUMO

Atherosclerotic plaques develop in the inner intimal layer of arteries and can cause heart attacks and strokes1. As plaques lack innervation, the effects of neuronal control on atherosclerosis remain unclear. However, the immune system responds to plaques by forming leukocyte infiltrates in the outer connective tissue coat of arteries (the adventitia)2-6. Here, because the peripheral nervous system uses the adventitia as its principal conduit to reach distant targets7-9, we postulated that the peripheral nervous system may directly interact with diseased arteries. Unexpectedly, widespread neuroimmune cardiovascular interfaces (NICIs) arose in mouse and human atherosclerosis-diseased adventitia segments showed expanded axon networks, including growth cones at axon endings near immune cells and media smooth muscle cells. Mouse NICIs established a structural artery-brain circuit (ABC): abdominal adventitia nociceptive afferents10-14 entered the central nervous system through spinal cord T6-T13 dorsal root ganglia and were traced to higher brain regions, including the parabrachial and central amygdala neurons; and sympathetic efferent neurons projected from medullary and hypothalamic neurons to the adventitia through spinal intermediolateral neurons and both coeliac and sympathetic chain ganglia. Moreover, ABC peripheral nervous system components were activated: splenic sympathetic and coeliac vagus nerve activities increased in parallel to disease progression, whereas coeliac ganglionectomy led to the disintegration of adventitial NICIs, reduced disease progression and enhanced plaque stability. Thus, the peripheral nervous system uses NICIs to assemble a structural ABC, and therapeutic intervention in the ABC attenuates atherosclerosis.


Assuntos
Aterosclerose , Placa Aterosclerótica , Animais , Aterosclerose/prevenção & controle , Progressão da Doença , Gânglios Espinais , Gânglios Simpáticos , Camundongos , Neurônios/fisiologia , Placa Aterosclerótica/prevenção & controle
7.
Mol Cell ; 80(4): 607-620.e12, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-33113344

RESUMO

Aberrant mitophagy has been implicated in a broad spectrum of disorders. PINK1, Parkin, and ubiquitin have pivotal roles in priming mitophagy. However, the entire regulatory landscape and the precise control mechanisms of mitophagy remain to be elucidated. Here, we uncover fundamental mitophagy regulation involving PINK1 and a non-canonical role of the mitochondrial Tu translation elongation factor (TUFm). The mitochondrion-cytosol dual-localized TUFm interacts with PINK1 biochemically and genetically, which is an evolutionarily conserved Parkin-independent route toward mitophagy. A PINK1-dependent TUFm phosphoswitch at Ser222 determines conversion from activating to suppressing mitophagy. PINK1 modulates differential translocation of TUFm because p-S222-TUFm is restricted predominantly to the cytosol, where it inhibits mitophagy by impeding Atg5-Atg12 formation. The self-antagonizing feature of PINK1/TUFm is critical for the robustness of mitophagy regulation, achieved by the unique kinetic parameters of p-S222-TUFm, p-S65-ubiquitin, and their common kinase PINK1. Our findings provide new mechanistic insights into mitophagy and mitophagy-associated disorders.


Assuntos
Drosophila melanogaster/crescimento & desenvolvimento , Mitocôndrias/patologia , Proteínas Mitocondriais/metabolismo , Mitofagia , Fator Tu de Elongação de Peptídeos/metabolismo , Proteínas Quinases/metabolismo , Animais , Citosol/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Células HeLa , Humanos , Masculino , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Fator Tu de Elongação de Peptídeos/genética , Fosforilação , Domínios e Motivos de Interação entre Proteínas , Proteínas Quinases/genética , Transporte Proteico , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
8.
Development ; 151(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38512324

RESUMO

The conserved MRE11-RAD50-NBS1/Xrs2 complex is crucial for DNA break metabolism and genome maintenance. Although hypomorphic Rad50 mutation mice showed normal meiosis, both null and hypomorphic rad50 mutation yeast displayed impaired meiosis recombination. However, the in vivo function of Rad50 in mammalian germ cells, particularly its in vivo role in the resection of meiotic double strand break (DSB) ends at the molecular level remains elusive. Here, we have established germ cell-specific Rad50 knockout mouse models to determine the role of Rad50 in mitosis and meiosis of mammalian germ cells. We find that Rad50-deficient spermatocytes exhibit defective meiotic recombination and abnormal synapsis. Mechanistically, using END-seq, we demonstrate reduced DSB formation and abnormal DSB end resection occurs in mutant spermatocytes. We further identify that deletion of Rad50 in gonocytes leads to complete loss of spermatogonial stem cells due to genotoxic stress. Taken together, our results reveal the essential role of Rad50 in mammalian germ cell meiosis and mitosis, and provide in vivo views of RAD50 function in meiotic DSB formation and end resection at the molecular level.


Assuntos
Quebras de DNA de Cadeia Dupla , Animais , Masculino , Camundongos , Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Endodesoxirribonucleases/genética , Endodesoxirribonucleases/metabolismo , Mutação com Perda de Função , Mamíferos/metabolismo , Meiose/genética , Mutação , Espermatócitos/metabolismo , Células Germinativas/metabolismo , Hidrolases Anidrido Ácido/genética , Hidrolases Anidrido Ácido/metabolismo
9.
Am J Hum Genet ; 110(11): 1919-1937, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37827158

RESUMO

Misregulation of histone lysine methylation is associated with several human cancers and with human developmental disorders. DOT1L is an evolutionarily conserved gene encoding a lysine methyltransferase (KMT) that methylates histone 3 lysine-79 (H3K79) and was not previously associated with a Mendelian disease in OMIM. We have identified nine unrelated individuals with seven different de novo heterozygous missense variants in DOT1L through the Undiagnosed Disease Network (UDN), the SickKids Complex Care genomics project, and GeneMatcher. All probands had some degree of global developmental delay/intellectual disability, and most had one or more major congenital anomalies. To assess the pathogenicity of the DOT1L variants, functional studies were performed in Drosophila and human cells. The fruit fly DOT1L ortholog, grappa, is expressed in most cells including neurons in the central nervous system. The identified DOT1L variants behave as gain-of-function alleles in flies and lead to increased H3K79 methylation levels in flies and human cells. Our results show that human DOT1L and fly grappa are required for proper development and that de novo heterozygous variants in DOT1L are associated with a Mendelian disease.


Assuntos
Anormalidades Congênitas , Deficiências do Desenvolvimento , Histona-Lisina N-Metiltransferase , Humanos , Mutação com Ganho de Função , Histona-Lisina N-Metiltransferase/genética , Histonas/genética , Histonas/metabolismo , Lisina , Metilação , Metiltransferases/genética , Neoplasias/genética , Drosophila/genética , Proteínas de Drosophila/genética , Deficiências do Desenvolvimento/genética , Anormalidades Congênitas/genética
10.
Nucleic Acids Res ; 52(D1): D404-D412, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37522378

RESUMO

With the progress of structural biology, the Protein Data Bank (PDB) has witnessed rapid accumulation of experimentally solved protein structures. Since many structures are determined with purification and crystallization additives that are unrelated to a protein's in vivo function, it is nontrivial to identify the subset of protein-ligand interactions that are biologically relevant. We developed the BioLiP2 database (https://zhanggroup.org/BioLiP) to extract biologically relevant protein-ligand interactions from the PDB database. BioLiP2 assesses the functional relevance of the ligands by geometric rules and experimental literature validations. The ligand binding information is further enriched with other function annotations, including Enzyme Commission numbers, Gene Ontology terms, catalytic sites, and binding affinities collected from other databases and a manual literature survey. Compared to its predecessor BioLiP, BioLiP2 offers significantly greater coverage of nucleic acid-protein interactions, and interactions involving large complexes that are unavailable in PDB format. BioLiP2 also integrates cutting-edge structural alignment algorithms with state-of-the-art structure prediction techniques, which for the first time enables composite protein structure and sequence-based searching and significantly enhances the usefulness of the database in structure-based function annotations. With these new developments, BioLiP2 will continue to be an important and comprehensive database for docking, virtual screening, and structure-based protein function analyses.


Assuntos
Algoritmos , Bases de Dados de Proteínas , Proteínas , Sítios de Ligação , Ligantes , Proteínas/química
11.
Plant J ; 118(5): 1327-1342, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38319946

RESUMO

Anthocyanin generation in apples (Malus domestica) and the pigmentation that results from it may be caused by irradiation and through administration of methyl jasmonate (MeJA). However, their regulatory interrelationships associated with fruit coloration are not well defined. To determine whether MdERF109, a transcription factor (TF) involved in light-mediated coloration and anthocyanin biosynthesis, has synergistic effects with other proteins, we performed a yeast two-hybrid assessment and identified another TF, MdWER. MdWER was induced by MeJA treatment, and although overexpression of MdWER alone did not promote anthocyanin accumulation co-overexpression with MdERF109 resulted in significantly increase in anthocyanin biosynthesis. MdWER may form a protein complex with MdERF109 to promote anthocyanin accumulation by enhancing combinations between the proteins and their corresponding genes. In addition, MdWER, as a MeJA responsive protein, interacts with the anthocyanin repressor MdJAZ2. Transient co-expression in apple fruit and protein interaction assays allowed us to conclude that MdERF109 and MdJAZ2 interact with MdWER and take part in the production of anthocyanins upon MeJA treatment and irradiation. Our findings validate a role for the MdERF109-MdWER-MdJAZ2 module in anthocyanin biosynthesis and uncover a novel mechanism for how light and MeJA signals are coordinated anthocyanin biosynthesis in apple fruit.


Assuntos
Acetatos , Antocianinas , Ciclopentanos , Frutas , Regulação da Expressão Gênica de Plantas , Luz , Malus , Oxilipinas , Proteínas de Plantas , Ciclopentanos/metabolismo , Oxilipinas/metabolismo , Antocianinas/metabolismo , Antocianinas/biossíntese , Acetatos/farmacologia , Acetatos/metabolismo , Malus/metabolismo , Malus/genética , Malus/efeitos da radiação , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Frutas/metabolismo , Frutas/genética , Frutas/efeitos da radiação , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Reguladores de Crescimento de Plantas/metabolismo
12.
Hum Mol Genet ; 32(6): 984-997, 2023 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-36255738

RESUMO

SUPT16H encodes the large subunit of the FAcilitate Chromatin Transcription (FACT) complex, which functions as a nucleosome organizer during transcription. We identified two individuals from unrelated families carrying de novo missense variants in SUPT16H. The probands exhibit global developmental delay, intellectual disability, epilepsy, facial dysmorphism and brain structural abnormalities. We used Drosophila to characterize two variants: p.T171I and p.G808R. Loss of the fly ortholog, dre4, causes lethality at an early developmental stage. RNAi-mediated knockdown of dre4 in either glia or neurons causes severely reduced eclosion and longevity. Tissue-specific knockdown of dre4 in the eye or wing leads to the loss of these tissues, whereas overexpression of SUPT16H has no dominant effect. Moreover, expression of the reference SUPT16H significantly rescues the loss-of-function phenotypes in the nervous system as well as wing and eye. In contrast, expression of SUPT16H p.T171I or p.G808R rescues the phenotypes poorly, indicating that the variants are partial loss-of-function alleles. While previous studies argued that the developmental arrest caused by loss of dre4 is due to impaired ecdysone production in the prothoracic gland, our data show that dre4 is required for proper cell growth and survival in multiple tissues in a cell-autonomous manner. Altogether, our data indicate that the de novo loss-of-function variants in SUPT16H are indeed associated with developmental and neurological defects observed in the probands.


Assuntos
Encefalopatias , Epilepsia , Deficiência Intelectual , Transtornos do Neurodesenvolvimento , Animais , Sobrevivência Celular , Transtornos do Neurodesenvolvimento/genética , Deficiência Intelectual/genética , Mutação de Sentido Incorreto , Drosophila
13.
Nat Methods ; 19(2): 195-204, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35132244

RESUMO

Cryo-electron microscopy (cryo-EM) has become a leading approach for protein structure determination, but it remains challenging to accurately model atomic structures with cryo-EM density maps. We propose a hybrid method, CR-I-TASSER (cryo-EM iterative threading assembly refinement), which integrates deep neural-network learning with I-TASSER assembly simulations for automated cryo-EM structure determination. The method is benchmarked on 778 proteins with simulated and experimental density maps, where CR-I-TASSER constructs models with a correct fold (template modeling (TM) score >0.5) for 643 targets that is 64% higher than the best of some other de novo and refinement-based approaches on high-resolution data samples. Detailed data analyses showed that the main advantage of CR-I-TASSER lies in the deep learning-based Cα position prediction, which significantly improves the threading template quality and therefore boosts the accuracy of final models through optimized fragment assembly simulations. These results demonstrate a new avenue to determine cryo-EM protein structures with high accuracy and robustness covering various target types and density map resolutions.


Assuntos
Microscopia Crioeletrônica/métodos , Proteínas/química , Software , Biologia Computacional/métodos , Modelos Moleculares , Complexos Multiproteicos/química , Redes Neurais de Computação , Conformação Proteica
14.
Brief Bioinform ; 24(2)2023 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-36892153

RESUMO

Accurate and effective drug-target interaction (DTI) prediction can greatly shorten the drug development lifecycle and reduce the cost of drug development. In the deep-learning-based paradigm for predicting DTI, robust drug and protein feature representations and their interaction features play a key role in improving the accuracy of DTI prediction. Additionally, the class imbalance problem and the overfitting problem in the drug-target dataset can also affect the prediction accuracy, and reducing the consumption of computational resources and speeding up the training process are also critical considerations. In this paper, we propose shared-weight-based MultiheadCrossAttention, a precise and concise attention mechanism that can establish the association between target and drug, making our models more accurate and faster. Then, we use the cross-attention mechanism to construct two models: MCANet and MCANet-B. In MCANet, the cross-attention mechanism is used to extract the interaction features between drugs and proteins for improving the feature representation ability of drugs and proteins, and the PolyLoss loss function is applied to alleviate the overfitting problem and the class imbalance problem in the drug-target dataset. In MCANet-B, the robustness of the model is improved by combining multiple MCANet models and prediction accuracy further increases. We train and evaluate our proposed methods on six public drug-target datasets and achieve state-of-the-art results. In comparison with other baselines, MCANet saves considerable computational resources while maintaining accuracy in the leading position; however, MCANet-B greatly improves prediction accuracy by combining multiple models while maintaining a balance between computational resource consumption and prediction accuracy.


Assuntos
Desenvolvimento de Medicamentos , Descoberta de Drogas , Descoberta de Drogas/métodos , Proteínas/metabolismo , Sistemas de Liberação de Medicamentos , Domínios Proteicos
15.
Plant Physiol ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630866

RESUMO

Ginkgo (Ginkgo biloba L.) is one of the earliest extant species in seed plant phylogeny. Embryo development patterns can provide fundamental evidence for the origin, evolution, and adaptation of seeds. However, the architectural and morphological dynamics during embryogenesis in Ginkgo biloba (G. biloba) remain elusive. Herein, we obtained over 2200 visual slices from three stages of embryo development using micro-computed tomography imaging with improved staining methods. Based on 3D spatio-temporal pattern analysis, we found that a shoot apical meristem with seven highly differentiated leaf primordia, including apical and axillary leaf buds, is present in mature Ginkgo embryos. 3D rendering from the front, top, and side views showed two separate transport systems of tracheids located in the hypocotyl and cotyledon, representing a unique pattern of embryogenesis. Furthermore, the morphological dynamic analysis of secretory cavities indicated their strong association with cotyledons during development. In addition, we identified genes GbLBD25a (lateral organ boundaries domain 25a), GbCESA2a (cellulose synthase 2a), GbMYB74c (myeloblastosis 74c), GbPIN2 (PIN-FORMED 2) associated with vascular development regulation, and GbWRKY1 (WRKYGOK 1), GbbHLH12a (basic helix-loop-helix 12a), GbJAZ4 (jasmonate zim-domain 4) potentially involved in the formation of secretory cavities. Moreover, we found that flavonoid accumulation in mature embryos could enhance post-germinative growth and seedling establishment in harsh environments. Our 3D spatial reconstruction technique combined with multi-omics analysis opens avenues for investigating developmental architecture and molecular mechanisms during embryogenesis and lays the foundation for evolutionary studies of embryo development and maturation.

16.
Mol Psychiatry ; 29(5): 1253-1264, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38228891

RESUMO

The pathophysiology of autism spectrum disorders (ASDs) is causally linked to postsynaptic scaffolding proteins, as evidenced by numerous large-scale genomic studies [1, 2] and in vitro and in vivo neurobiological studies of mutations in animal models [3, 4]. However, due to the distinct phenotypic and genetic heterogeneity observed in ASD patients, individual mutation genes account for only a small proportion (<2%) of cases [1, 5]. Recently, a human genetic study revealed a correlation between de novo variants in FERM domain-containing-5 (FRMD5) and neurodevelopmental abnormalities [6]. In this study, we demonstrate that deficiency of the scaffolding protein FRMD5 leads to neurodevelopmental dysfunction and ASD-like behavior in mice. FRMD5 deficiency results in morphological abnormalities in neurons and synaptic dysfunction in mice. Frmd5-deficient mice display learning and memory dysfunction, impaired social function, and increased repetitive stereotyped behavior. Mechanistically, tandem mass tag (TMT)-labeled quantitative proteomics revealed that FRMD5 deletion affects the distribution of synaptic proteins involved in the pathological process of ASD. Collectively, our findings delineate the critical role of FRMD5 in neurodevelopment and ASD pathophysiology, suggesting potential therapeutic implications for the treatment of ASD.


Assuntos
Transtorno do Espectro Autista , Modelos Animais de Doenças , Proteínas de Membrana , Transtornos do Neurodesenvolvimento , Animais , Camundongos , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/metabolismo , Transtornos do Neurodesenvolvimento/genética , Transtornos do Neurodesenvolvimento/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Masculino , Neurônios/metabolismo , Comportamento Animal/fisiologia , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Camundongos Knockout , Transtorno Autístico/genética , Transtorno Autístico/metabolismo , Camundongos Endogâmicos C57BL , Comportamento Social , Comportamento Estereotipado , Sinapses/metabolismo , Feminino
17.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38220573

RESUMO

Diabetes mellitus (DM) causes damage to the central nervous system, resulting in cognitive impairment. Fibroblast growth factor 21 (FGF21) exhibits the potential to alleviate neurodegeneration. However, the therapeutic effect of intracerebroventricular (i.c.v) FGF21 infusion on diabetes-induced cognitive decline (DICD) and its potential mechanisms remain unclear. In this study, the impact of FGF21 on DICD was explored, and 1H nuclear magnetic resonance (NMR)-based metabolomics plus 13C NMR spectroscopy in combine with intravenous [1-13C]-glucose infusion were used to investigate the underlying metabolic mechanism. Results revealed that i.c.v FGF21 infusion effectively improved learning and memory performance of DICD mice; neuron loss and apoptosis in hippocampus and cortex were significantly blocked, suggesting a potential neuroprotective role of FGF21 in DICD. Metabolomics results revealed that FGF21 modulated DICD metabolic alterations related to glucose and neurotransmitter metabolism, which are characterized by distinct recovered enrichment of [3-13C]-lactate, [3-13C]-aspartate, [4-13C]-glutamine, [3-13C]-glutamine, [4-13C]-glutamate, and [4-13C]- γ-aminobutyric acid (GABA) from [1-13C]-glucose. Moreover, diabetes-induced neuron injury and metabolic dysfunctions might be mediated by PI3K/AKT/GSK-3ß signaling pathway inactivation in the hippocampus and cortex, which were activated by i.c.v injection of FGF21. These findings indicate that i.c.v FGF21 infusion exerts its neuroprotective effect on DICD by remodeling cerebral glucose and neurotransmitter metabolism by activating the PI3K/AKT/GSK-3ß signaling pathway.


Assuntos
Disfunção Cognitiva , Diabetes Mellitus , Fatores de Crescimento de Fibroblastos , Camundongos , Animais , Glutamina/metabolismo , Glicogênio Sintase Quinase 3 beta , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases , Ácido Glutâmico/metabolismo , Glucose/metabolismo , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Neurotransmissores
18.
Cell Mol Life Sci ; 81(1): 317, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39066891

RESUMO

Inner dynein arms (IDAs) are formed from a protein complex that is essential for appropriate flagellar bending and beating. IDA defects have previously been linked to the incidence of asthenozoospermia (AZS) and male infertility. The testes-enriched ZMYND12 protein is homologous with an IDA component identified in Chlamydomonas. ZMYND12 deficiency has previously been tied to infertility in males, yet the underlying mechanism remains uncertain. Here, a CRISPR/Cas9 approach was employed to generate Zmynd12 knockout (Zmynd12-/-) mice. These Zmynd12-/- mice exhibited significant male subfertility, reduced sperm motile velocity, and impaired capacitation. Through a combination of co-immunoprecipitation and mass spectrometry, ZMYND12 was found to interact with TTC29 and PRKACA. Decreases in the levels of PRKACA were evident in the sperm of these Zmynd12-/- mice, suggesting that this change may account for the observed drop in male fertility. Moreover, in a cohort of patients with AZS, one patient carrying a ZMYND12 variant was identified, expanding the known AZS-related variant spectrum. Together, these findings demonstrate that ZMYND12 is essential for flagellar beating, capacitation, and male fertility.


Assuntos
Infertilidade Masculina , Camundongos Knockout , Motilidade dos Espermatozoides , Animais , Masculino , Motilidade dos Espermatozoides/genética , Camundongos , Infertilidade Masculina/genética , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Dineínas/metabolismo , Dineínas/genética , Espermatozoides/metabolismo , Humanos , Astenozoospermia/genética , Astenozoospermia/metabolismo , Astenozoospermia/patologia , Capacitação Espermática/genética , Camundongos Endogâmicos C57BL , Sistemas CRISPR-Cas
19.
Cell Mol Life Sci ; 81(1): 233, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780775

RESUMO

Patients with head and neck squamous cell carcinoma (HNSCC) are at a high risk of developing recurrence and secondary cancers. This study evaluates the prognostic and surveillance utilities of circulating tumour cells (CTCs) in HNSCC. A total of 154 HNSCC patients were recruited and followed up for 4.5 years. Blood samples were collected at baseline and follow-up. CTCs were isolated using a spiral microfluid device. Recurrence and death due to cancer were assessed during the follow-up period. In patients with HNSCC, the presence of CTCs at baseline was a predictor of recurrence (OR = 8.40, p < 0.0001) and death (OR= ∞, p < 0.0001). Patients with CTCs at baseline had poor survival outcomes (p < 0.0001). Additionally, our study found that patients with CTCs in a follow-up appointment were 2.5 times more likely to experience recurrence or death from HNSCC (p < 0.05) prior to their next clinical visit. Our study highlights the prognostic and monitoring utilities of CTCs' in HNSCC patients. Early identification of CTCs facilitates precise risk assessment, guiding treatment choices and ultimately enhancing patient outcomes.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Recidiva Local de Neoplasia , Células Neoplásicas Circulantes , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Células Neoplásicas Circulantes/patologia , Células Neoplásicas Circulantes/metabolismo , Masculino , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/sangue , Neoplasias de Cabeça e Pescoço/diagnóstico , Feminino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Carcinoma de Células Escamosas de Cabeça e Pescoço/sangue , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico , Idoso , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/diagnóstico , Prognóstico , Adulto , Seguimentos
20.
Nano Lett ; 24(31): 9675-9682, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39058271

RESUMO

Feeding silkworms with functional materials as additives to produce naturally modified silk is a facile, diverse, controllable, and environmentally friendly method with a low cost of time and investment. Among various additives, carbon dots (CDs) show unique advantages due to their excellent biocompatibility and fluorescence stability. Here, a new type of green fluorescent carbon dots (G-CDs) is synthesized with a high oil-water partition ratio of 147, a low isoelectric point of 5.16, an absolute quantum yield of 71%, and critically controlled surface states. After feeding with G-CDs, the silkworms weave light yellow cocoons whose green fluorescence is visible to the naked eye under UV light. The luminous silk is sewn onto the cloth to create striking patterns with beautiful fluorescence. Such G-CDs have no adverse effect on the survival rate and the life cycle of silkworms and enable their whole bodies to glow under UV light. Based on the strong fluorescence, chemical stability, and biological safety, G-CDs are found in the digestive tracts, silk glands, feces, cocoons, and even moth bodies. G-CDs accumulate in the posterior silk glands where fibroin protein is secreted, indicating its stronger combination with fibroin than sericin, which meets the requirements for practical applications.


Assuntos
Bombyx , Carbono , Pontos Quânticos , Seda , Animais , Seda/química , Carbono/química , Pontos Quânticos/química , Fibroínas/química , Raios Ultravioleta , Fluorescência , Corantes Fluorescentes/química , Propriedades de Superfície
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