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1.
Proc Natl Acad Sci U S A ; 121(20): e2321711121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38713624

RESUMO

During development, neural stem cells in the cerebral cortex, also known as radial glial cells (RGCs), generate excitatory neurons, followed by production of cortical macroglia and inhibitory neurons that migrate to the olfactory bulb (OB). Understanding the mechanisms for this lineage switch is fundamental for unraveling how proper numbers of diverse neuronal and glial cell types are controlled. We and others recently showed that Sonic Hedgehog (Shh) signaling promotes the cortical RGC lineage switch to generate cortical oligodendrocytes and OB interneurons. During this process, cortical RGCs generate intermediate progenitor cells that express critical gliogenesis genes Ascl1, Egfr, and Olig2. The increased Ascl1 expression and appearance of Egfr+ and Olig2+ cortical progenitors are concurrent with the switch from excitatory neurogenesis to gliogenesis and OB interneuron neurogenesis in the cortex. While Shh signaling promotes Olig2 expression in the developing spinal cord, the exact mechanism for this transcriptional regulation is not known. Furthermore, the transcriptional regulation of Olig2 and Egfr has not been explored. Here, we show that in cortical progenitor cells, multiple regulatory programs, including Pax6 and Gli3, prevent precocious expression of Olig2, a gene essential for production of cortical oligodendrocytes and astrocytes. We identify multiple enhancers that control Olig2 expression in cortical progenitors and show that the mechanisms for regulating Olig2 expression are conserved between the mouse and human. Our study reveals evolutionarily conserved regulatory logic controlling the lineage switch of cortical neural stem cells.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Córtex Cerebral , Receptores ErbB , Proteínas Hedgehog , Proteínas do Tecido Nervoso , Células-Tronco Neurais , Neurogênese , Fator de Transcrição 2 de Oligodendrócitos , Fator de Transcrição PAX6 , Animais , Neurogênese/fisiologia , Córtex Cerebral/metabolismo , Córtex Cerebral/citologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Receptores ErbB/metabolismo , Receptores ErbB/genética , Camundongos , Fator de Transcrição 2 de Oligodendrócitos/metabolismo , Fator de Transcrição 2 de Oligodendrócitos/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas do Tecido Nervoso/genética , Proteínas Hedgehog/metabolismo , Proteínas Hedgehog/genética , Fator de Transcrição PAX6/metabolismo , Fator de Transcrição PAX6/genética , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/citologia , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/genética , Proteína Gli3 com Dedos de Zinco/metabolismo , Proteína Gli3 com Dedos de Zinco/genética , Proteínas do Olho/metabolismo , Proteínas do Olho/genética , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Fatores de Transcrição Box Pareados/metabolismo , Fatores de Transcrição Box Pareados/genética , Neuroglia/metabolismo , Neuroglia/citologia , Regulação da Expressão Gênica no Desenvolvimento , Transdução de Sinais , Bulbo Olfatório/metabolismo , Bulbo Olfatório/citologia , Linhagem da Célula , Humanos
2.
CNS Neurosci Ther ; 30(4): e14708, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38600857

RESUMO

AIMS: Sleep disturbance is a prevalent nonmotor symptom of Parkinson's disease (PD), however, assessing sleep conditions is always time-consuming and labor-intensive. In this study, we performed an automatic sleep-wake state classification and early diagnosis of PD by analyzing the electrocorticography (ECoG) and electromyogram (EMG) signals of both normal and PD rats. METHODS: The study utilized ECoG power, EMG amplitude, and corticomuscular coherence values extracted from normal and PD rats to construct sleep-wake scoring models based on the support vector machine algorithm. Subsequently, we incorporated feature values that could act as diagnostic markers for PD and then retrained the models, which could encompass the identification of vigilance states and the diagnosis of PD. RESULTS: Features extracted from occipital ECoG signals were more suitable for constructing sleep-wake scoring models than those from frontal ECoG (average Cohen's kappa: 0.73 vs. 0.71). Additionally, after retraining, the new models demonstrated increased sensitivity to PD and accurately determined the sleep-wake states of rats (average Cohen's kappa: 0.79). CONCLUSION: This study accomplished the precise detection of substantia nigra lesions and the monitoring of sleep-wake states. The integration of circadian rhythm monitoring and disease state assessment has the potential to improve the efficacy of therapeutic strategies considerably.


Assuntos
Doença de Parkinson , Ratos , Animais , Doença de Parkinson/diagnóstico , Máquina de Vetores de Suporte , Eletroencefalografia , Sono , Vigília
3.
Cell Insight ; 3(3): 100162, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38595769

RESUMO

The ciliary body, located at the junction of the choroid and iris, is crucial in the development of the embryonic eye. Notch2 signalling, Wnt signalling, transforming growth factor ß (TGF-ß) signalling, and Pax6 signalling are critical for coordinating the ciliary body formation. These signalling pathways are coordinated with each other and participate in the ciliary body development, ensuring the precise formation and optimal functioning of the eye structure. Although rare, ciliary body hypoplasia, ciliary tumours, and genetic-related iritis indicate the intricate nature of ciliary body development. Given the ciliary body's important biological significance and potential medical relevance, we aim to provide a comprehensive overview of the developmental molecular mechanisms governing ciliary body formation and function. Here, we focus on the intricate signalling pathways governing ciliary body development and corresponding genetic ciliary diseases.

4.
bioRxiv ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38562687

RESUMO

Progression through the G1 phase of the cell cycle is the most highly regulated step in cellular division. We employed a chemogenomics approach to discover novel cellular networks that regulate cell cycle progression. This approach uncovered functional clusters of genes that altered sensitivity of cells to inhibitors of the G1/S transition. Mutation of components of the Polycomb Repressor Complex 2 rescued growth inhibition caused by the CDK4/6 inhibitor palbociclib, but not to inhibitors of S phase or mitosis. In addition to its core catalytic subunits, mutation of the PRC2.1 accessory protein MTF2, but not the PRC2.2 protein JARID2, rendered cells resistant to palbociclib treatment. We found that PRC2.1 (MTF2), but not PRC2.2 (JARID2), was critical for promoting H3K27me3 deposition at CpG islands genome-wide and in promoters. This included the CpG islands in the promoter of the CDK4/6 cyclins CCND1 and CCND2, and loss of MTF2 lead to upregulation of both CCND1 and CCND2. Our results demonstrate a role for PRC2.1, but not PRC2.2, in promoting G1 progression.

5.
Cell Rep ; 43(4): 114010, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38536817

RESUMO

Although the small GTPase RAB37 acts as an organizer of autophagosome biogenesis, the upstream regulatory mechanism of autophagy via guanosine diphosphate (GDP)-guanosine triphosphate (GTP) exchange in maintaining retinal function has not been determined. We found that retinitis pigmentosa GTPase regulator (RPGR) is a guanine nucleotide exchange factor that activates RAB37 by accelerating GDP-to-GTP exchange. RPGR directly interacts with RAB37 via the RPGR-RCC1-like domain to promote autophagy through stimulating exchange. Rpgr knockout (KO) in mice leads to photoreceptor degeneration owing to autophagy impairment in the retina. Notably, the retinopathy phenotypes of Rpgr KO retinas are rescued by the adeno-associated virus-mediated transfer of pre-trans-splicing molecules, which produce normal Rpgr mRNAs via trans-splicing in the Rpgr KO retinas. This rescue upregulates autophagy through the re-expression of RPGR in KO retinas to accelerate GDP-to-GTP exchange; thus, retinal homeostasis reverts to normal. Taken together, these findings provide an important missing link for coordinating RAB37 GDP-GTP exchange via the RPGR and retinal homeostasis by autophagy regulation.


Assuntos
Autofagia , Proteínas de Transporte , Proteínas do Olho , Fatores de Troca do Nucleotídeo Guanina , Camundongos Knockout , Retina , Proteínas rab de Ligação ao GTP , Animais , Retina/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Proteínas rab de Ligação ao GTP/genética , Camundongos , Humanos , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Proteínas do Olho/metabolismo , Proteínas do Olho/genética , Células HEK293 , Camundongos Endogâmicos C57BL , Guanosina Trifosfato/metabolismo , Guanosina Difosfato/metabolismo , Ligação Proteica
6.
Nat Methods ; 21(4): 723-734, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38504114

RESUMO

The ENCODE Consortium's efforts to annotate noncoding cis-regulatory elements (CREs) have advanced our understanding of gene regulatory landscapes. Pooled, noncoding CRISPR screens offer a systematic approach to investigate cis-regulatory mechanisms. The ENCODE4 Functional Characterization Centers conducted 108 screens in human cell lines, comprising >540,000 perturbations across 24.85 megabases of the genome. Using 332 functionally confirmed CRE-gene links in K562 cells, we established guidelines for screening endogenous noncoding elements with CRISPR interference (CRISPRi), including accurate detection of CREs that exhibit variable, often low, transcriptional effects. Benchmarking five screen analysis tools, we find that CASA produces the most conservative CRE calls and is robust to artifacts of low-specificity single guide RNAs. We uncover a subtle DNA strand bias for CRISPRi in transcribed regions with implications for screen design and analysis. Together, we provide an accessible data resource, predesigned single guide RNAs for targeting 3,275,697 ENCODE SCREEN candidate CREs with CRISPRi and screening guidelines to accelerate functional characterization of the noncoding genome.


Assuntos
Sistemas CRISPR-Cas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Humanos , Sistemas CRISPR-Cas/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , RNA Guia de Sistemas CRISPR-Cas , Genoma , Células K562
7.
Proc Natl Acad Sci U S A ; 121(7): e2310430121, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38315854

RESUMO

Phase separation (PS) drives the formation of biomolecular condensates that are emerging biological structures involved in diverse cellular processes. Recent studies have unveiled PS-induced formation of several transcriptional factor (TF) condensates that are transcriptionally active, but how strongly PS promotes gene activation remains unclear. Here, we show that the oncogenic TF fusion Yes-associated protein 1-Mastermind like transcriptional coactivator 2 (YAP-MAML2) undergoes PS and forms liquid-like condensates that bear the hallmarks of transcriptional activity. Furthermore, we examined the contribution of PS to YAP-MAML2-mediated gene expression by developing a chemogenetic tool that dissolves TF condensates, allowing us to compare phase-separated and non-phase-separated conditions at identical YAP-MAML2 protein levels. We found that a small fraction of YAP-MAML2-regulated genes is further affected by PS, which include the canonical YAP target genes CTGF and CYR61, and other oncogenes. On the other hand, majority of YAP-MAML2-regulated genes are not affected by PS, highlighting that transcription can be activated effectively by diffuse complexes of TFs with the transcriptional machinery. Our work opens new directions in understanding the role of PS in selective modulation of gene expression, suggesting differential roles of PS in biological processes.


Assuntos
Separação de Fases , Transcriptoma , Fatores de Transcrição/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Oncogenes
8.
Acta Neurol Belg ; 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347315

RESUMO

BACKGROUND AND OBJECTIVE: The effectiveness and long-term efficacy of edaravone, a recommended treatment for amyotrophic lateral sclerosis (ALS), has not been examined in real-world settings. This study aims to evaluate the effectiveness and long-term efficacy of edaravone. METHODS: The OVID Medline, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science databases were searched for articles published between January 1, 2000, and May 1, 2023. Two investigators independently screened the retrieved articles for randomized controlled trials (RCTs), cohort studies, or single-arm trials that evaluated the effect of edaravone on amyotrophic lateral sclerosis (ALS). The risk of bias was evaluated using the revised Cochrane Risk-of-Bias (RoB 2.0) tool for randomized controlled trials (RCTs) and the Risk-of-Bias In Non-randomized Studies of Interventions (ROBINS-I) tool for observational studies. The primary outcome was the ALSFRS-R score assessed at month 6, with secondary outcomes including the ALSFRS-R scores evaluated at months 9, 12, and 18, forced vital capacity (FVC), and adverse events. The certainty of evidence was assessed using the GRADE approach. RESULTS: The analysis included 16 studies with a total of 4828 participants. Among these, four were randomized controlled trials (RCTs) and 12 were observational studies. Of the RCTs, four were rated as having a low risk of bias, while six of the observational studies were rated as having a low risk of bias. Edaravone was associated with slightly slower progression in the reduction of ALSFRS-R score at month 6 compared to placebo (mean difference 1.01, 95%CI -0.87 to 3.09, p = 0.293), as shown by evidence from RCTs. However, observational studies did not show any benefit of adding edaravone to routine practice (mean difference 1.85, 95%CI -2.05 to 5.75, p = 0.352). The change from baseline in ALSFRS-R score was -2.1, -4.04, -7.5, -6.82, and -7.9 at months 3, 6, 9, 12, and 18, respectively. The GRADE assessment indicated moderate certainty for evidence from RCTs, while evidence from observational studies had very low certainty. CONCLUSION: Due to the limited number of studies and confounding issues in observational studies, further examination of the added benefits of edaravone to routine practice is necessary through RCTs, particularly regarding its long-term efficacy.

9.
Aging (Albany NY) ; 16(1): 207-225, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38175687

RESUMO

Ovarian cancer (OC) ranks as the second leading cause of death among gynecological cancers. Numerous studies have indicated a correlation between the tumor microenvironment (TME) and the clinical response to treatment in OC patients. Tumor-associated macrophages (TAMs), a crucial component of the TME, exert influence on invasion, metastasis, and recurrence in OC patients. To delve deeper into the role of TAMs in OC, this study conducted an extensive analysis of single-cell data from OC patients. The aim is to develop a new risk score (RS) to characterize the response to treatment in OC patients to inform clinical treatment. We first identified TAM-associated genes (TAMGs) in OC patients and examined the protein and mRNA expression levels of TAMGs by Western blot and PCR experiments. Additionally, a scoring system for TAMGs was constructed, successfully categorizing patients into high and low RS subgroups. Remarkably, significant disparities were observed in immune cell infiltration and immunotherapy response between the high and low RS subgroups. The findings revealed that patients in the high RS group had a poorer prognosis but displayed greater sensitivity to immunotherapy. Another important finding was that patients in the high RS subgroup had a higher IC50 for chemotherapeutic agents. Furthermore, further experimental investigations led to the discovery that THEMIS2 could serve as a potential target in OC patients and is associated with EMT (epithelial-mesenchymal transition). Overall, the TAMGs-based scoring system holds promise for screening patients who would benefit from therapy and provides valuable information for the clinical treatment of OC.


Assuntos
Neoplasias Ovarianas , Macrófagos Associados a Tumor , Humanos , Feminino , Macrófagos Associados a Tumor/metabolismo , Macrófagos/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Transição Epitelial-Mesenquimal/genética , Microambiente Tumoral/genética
10.
J Int Med Res ; 52(1): 3000605231220871, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38235710

RESUMO

OBJECTIVE: To compare the efficacy and safety of the modified versus standard Valsalva maneuver in the treatment of paroxysmal supraventricular tachycardia (PSVT). METHODS: The PubMed, Embase, Web of Science, CNKI, WanFang Data, and VIP electronic databases were searched to identify studies comparing the modified and standard Valsalva maneuvers in the treatment of PSVT from database inception to 1 May 2023. Two reviewers independently screened the literature, extracted the data, and assessed the risk of bias of all included studies. RESULTS: Nineteen randomized controlled trials involving 2527 patients with PSVT were included. The overall rate of cardioversion was higher in the modified than standard Valsalva group (risk ratio [RR] = 1.80, 95% confidence interval [CI] = 1.61-2.01), as was the success rate of cardioversion after a single Valsalva maneuver (RR = 2.05, 95% CI = 1.74-2.41). There was no statistically significant difference in adverse reactions between the two groups (RR = 1.07, 95% CI = 0.82-1.38). CONCLUSION: Current evidence suggests that the modified Valsalva maneuver can significantly improve the success rate of cardioversion in patients with PSVT without increasing adverse reactions. The modified Valsalva maneuver is therefore worth promoting and should be considered as a routine first treatment.INPLASY registration number: 2023100092.


Assuntos
Taquicardia Paroxística , Taquicardia Ventricular , Humanos , Cardioversão Elétrica , Taquicardia Paroxística/terapia , Taquicardia Ventricular/terapia , Manobra de Valsalva , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
Neurosci Bull ; 40(3): 310-324, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37302108

RESUMO

Parvalbumin-positive retinal ganglion cells (PV+ RGCs) are an essential subset of RGCs found in various species. However, their role in transmitting visual information remains unclear. Here, we characterized PV+ RGCs in the retina and explored the functions of the PV+ RGC-mediated visual pathway. By applying multiple viral tracing strategies, we investigated the downstream of PV+ RGCs across the whole brain. Interestingly, we found that the PV+ RGCs provided direct monosynaptic input to PV+ excitatory neurons in the superficial layers of the superior colliculus (SC). Ablation or suppression of SC-projecting PV+ RGCs abolished or severely impaired the flight response to looming visual stimuli in mice without affecting visual acuity. Furthermore, using transcriptome expression profiling of individual cells and immunofluorescence colocalization for RGCs, we found that PV+ RGCs are predominant glutamatergic neurons. Thus, our findings indicate the critical role of PV+ RGCs in an innate defensive response and suggest a non-canonical subcortical visual pathway from excitatory PV+ RGCs to PV+ SC neurons that regulates looming visual stimuli. These results provide a potential target for intervening and treating diseases related to this circuit, such as schizophrenia and autism.


Assuntos
Colículos Superiores , Vias Visuais , Camundongos , Animais , Colículos Superiores/fisiologia , Células Ganglionares da Retina/fisiologia , Retina
12.
Mol Cell ; 83(24): 4633-4645.e9, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38134886

RESUMO

Despite tremendous progress in detecting DNA variants associated with human disease, interpreting their functional impact in a high-throughput and single-base resolution manner remains challenging. Here, we develop a pooled prime-editing screen method, PRIME, that can be applied to characterize thousands of coding and non-coding variants in a single experiment with high reproducibility. To showcase its applications, we first identified essential nucleotides for a 716 bp MYC enhancer via PRIME-mediated single-base resolution analysis. Next, we applied PRIME to functionally characterize 1,304 genome-wide association study (GWAS)-identified non-coding variants associated with breast cancer and 3,699 variants from ClinVar. We discovered that 103 non-coding variants and 156 variants of uncertain significance are functional via affecting cell fitness. Collectively, we demonstrate that PRIME is capable of characterizing genetic variants at single-base resolution and scale, advancing accurate genome annotation for disease risk prediction, diagnosis, and therapeutic target identification.


Assuntos
Genoma Humano , Estudo de Associação Genômica Ampla , Humanos , Genoma Humano/genética , Reprodutibilidade dos Testes , Sequências Reguladoras de Ácido Nucleico , DNA , Edição de Genes/métodos , Sistemas CRISPR-Cas
13.
Cell Rep ; 42(12): 113496, 2023 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-37995181

RESUMO

Appropriate histone modifications emerge as essential cell fate regulators of neuronal identities across neocortical areas and layers. Here we showed that NSD1, the methyltransferase for di-methylated lysine 36 of histone H3 (H3K36me2), controls both area and layer identities of the neocortex. Nsd1-ablated neocortex showed an area shift of all four primary functional regions and aberrant wiring of cortico-thalamic-cortical projections. Nsd1 conditional knockout mice displayed defects in spatial memory, motor learning, and coordination, resembling patients with the Sotos syndrome carrying NSD1 mutations. On Nsd1 loss, superficial-layer pyramidal neurons (PNs) progressively mis-expressed markers for deep-layer PNs, and PNs remained immature both morphologically and electrophysiologically. Loss of Nsd1 in postmitotic PNs causes genome-wide loss of H3K36me2 and re-distribution of DNA methylation, which accounts for diminished expression of neocortical layer specifiers but ectopic expression of non-neural genes. Together, H3K36me2 mediated by NSD1 is required for the establishment and maintenance of region- and layer-specific neocortical identities.


Assuntos
Histonas , Síndrome de Sotos , Animais , Humanos , Camundongos , Metilação de DNA , Histona-Lisina N-Metiltransferase/genética , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Mutação , Processamento de Proteína Pós-Traducional , Síndrome de Sotos/genética
14.
Front Cell Infect Microbiol ; 13: 1186335, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37860065

RESUMO

RATIONALE: T. marneffei is opportunistic and dimorphic fungus, which can cause systemic mycosis in human beings. It's being difficult to obtain histopathological or microbiological evidence in T. marneffei infection. We reported a rare non-HIV case of T. marneffei infection of bronchopulmonary and mediastinal lymph nodes which was diagnosed by EBUS-TBNA combined with mNGS. The high titer of anti-IFN-γ autoantibodies in serum was probably the cause of T. marneffei infection,which has yet to be fully known. PATIENT CONCERNS: A 56-year-old Chinese man presented with a 5-month history of intermittent low or high fever and dry cough, followed by fatigue, night sweating, and chest pain when coughing. A large hilar lesion in the left lung and multiple mediastinal lymph node enlargements were found on his chest CT scan. DIAGNOSES: The patient received EBUS-TBNA of hilar tissue and lymph node biopsy for mNGS at the second Ultrasonic bronchoscopy. No fungal hyphae or spores were found in the histopathology. There were high sequencing reads of T. marneffei in samples of lymph node fluid and bronchogenesis tissue detected by mNGS. His plasma anti-IFN-γ autoantibodies level was positive with a high titer at 1:2500↑. INTERVENTION: The patient went through atrial fibrillation at the first dose of amphotericin B liposomes and treated with voriconazole later. OUTCOMES: His fever, cough and dyspnea quickly disappeared since the fourth day of treatment. After six months, there was not any focus in his chest CT scans. But his plasma anti-IFN-γ autoantibodies remained unchanged. LESSONS: Complementing the traditional laboratory and bronchoscopy, mNGS combined with EBUS-TBNA facilitate rapid and precise diagnosis of bronchopulmonary mediastinal lymph nodes T. marneffei infection. Clinicians should be aware of anti-INF-γ autoantibodies in opportunistic infections of non-HIV patients.


Assuntos
Tosse , Micoses , Humanos , Masculino , Pessoa de Meia-Idade , Autoanticorpos/sangue , Autoanticorpos/imunologia , Tosse/patologia , Interferon gama , Linfonodos/patologia , Micoses/diagnóstico , Ultrassonografia de Intervenção
15.
Nat Genet ; 55(10): 1735-1744, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37735198

RESUMO

Candidate cis-regulatory elements (cCREs) in microglia demonstrate the most substantial enrichment for Alzheimer's disease (AD) heritability compared to other brain cell types. However, whether and how these genome-wide association studies (GWAS) variants contribute to AD remain elusive. Here we prioritize 308 previously unreported AD risk variants at 181 cCREs by integrating genetic information with microglia-specific 3D epigenome annotation. We further establish the link between functional variants and target genes by single-cell CRISPRi screening in microglia. In addition, we show that AD variants exhibit allelic imbalance on target gene expression. In particular, rs7922621 is the effective variant in controlling TSPAN14 expression among other nominated variants in the same cCRE and exerts multiple physiological effects including reduced cell surface ADAM10 and altered soluble TREM2 (sTREM2) shedding. Our work represents a systematic approach to prioritize and characterize AD-associated variants and provides a roadmap for advancing genetic association to experimentally validated cell-type-specific phenotypes and mechanisms.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Microglia/metabolismo , Estudo de Associação Genômica Ampla , Membrana Celular/metabolismo , Fenótipo
16.
Biomater Adv ; 153: 213579, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37566935

RESUMO

Engineering of myocardial tissues has become a promising therapeutic strategy for treating myocardial infarction (MI). However, a significant challenge remains in generating clinically relevant myocardial tissues that possess native microstructural characteristics and fulfill the requirements for implantation within the human body. In this study, a thick 3D myocardial construct with anisotropic myofibers and perfusable branched vascular channels is created with clinically relevant dimensions using a customized beam-scanning stereolithography printing technique. To obtain tissue-specific matrix niches, a decellularized extracellular matrix microfiber-reinforced gelatin-based bioink is developed. The bioink plays a crucial role in facilitating the precise manufacturing of a hierarchical microstructure, enabling us to better replicate the physiological characteristics of the native myocardial tissue matrix in terms of structure, biomechanics, and bioactivity. Through the integration of the tailored bioink with our printing method, we demonstrate a biomimetic architecture, appropriate biomechanical properties, vascularization, and improved functionality of induced pluripotent stem cell-derived cardiomyocytes in the thick tissue construct in vitro. This work not only offers a novel and effective means to generate biomimetic heart tissue in vitro for the treatment of MI, but also introduces a potential methodology for creating clinically relevant tissue products to aid in other complex tissue/organ regeneration and disease model applications.


Assuntos
Miocárdio , Engenharia Tecidual , Humanos , Engenharia Tecidual/métodos , Miócitos Cardíacos , Impressão Tridimensional , Estereolitografia
18.
bioRxiv ; 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37502948

RESUMO

Despite tremendous progress in detecting DNA variants associated with human disease, interpreting their functional impact in a high-throughput and base-pair resolution manner remains challenging. Here, we develop a novel pooled prime editing screen method, PRIME, which can be applied to characterize thousands of coding and non-coding variants in a single experiment with high reproducibility. To showcase its applications, we first identified essential nucleotides for a 716 bp MYC enhancer via PRIME-mediated saturation mutagenesis. Next, we applied PRIME to functionally characterize 1,304 non-coding variants associated with breast cancer and 3,699 variants from ClinVar. We discovered that 103 non-coding variants and 156 variants of uncertain significance are functional via affecting cell fitness. Collectively, we demonstrate PRIME capable of characterizing genetic variants at base-pair resolution and scale, advancing accurate genome annotation for disease risk prediction, diagnosis, and therapeutic target identification.

19.
Small ; 19(46): e2302962, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37518765

RESUMO

Retinal degeneration (RD) is an irreversible blinding disease that seriously affects patients' daily activities and mental health. Targeting hyperactivated microglia and regulating polarization are promising strategies for treating the disease. Mesenchymal stem cell (MSC) transplantation is proven to be an effective treatment due to its immunomodulatory and regenerative properties. However, the low efficiency of cell migration and integration of MSCs remains a major obstacle to clinical use. The goal of this study is to develop a nanodelivery system that targets hyperactivated microglia and inhibits their release of proinflammatory factors, to achieve durable neuroprotection. This approach is to engineer extracellular vesicles (EVs) isolated from MSC, modify them with a cyclic RGD (cRGD) peptide on their surface, and load them with an antagonist of the IL-1 receptor, anakinra. Comparing with non-engineered EVs, it is observed that engineered cRGD-EVs exhibit an increased targeting efficiency against hyperactivated microglia and strongly protected photoreceptors in experimental RD cells and animal models. This study provides a strategy to improve drug delivery to degenerated retinas and offers a promising approach to improve the treatment of RD through targeted modulation of the immune microenvironment via engineered cRGD-EVs.


Assuntos
Vesículas Extracelulares , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Degeneração Retiniana , Animais , Humanos , Degeneração Retiniana/terapia , Degeneração Retiniana/metabolismo , Vesículas Extracelulares/metabolismo , Retina
20.
bioRxiv ; 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37425940

RESUMO

Transcription factors (TFs) bind combinatorially to genomic cis-regulatory elements (cREs), orchestrating transcription programs. While studies of chromatin state and chromosomal interactions have revealed dynamic neurodevelopmental cRE landscapes, parallel understanding of the underlying TF binding lags. To elucidate the combinatorial TF-cRE interactions driving mouse basal ganglia development, we integrated ChIP-seq for twelve TFs, H3K4me3-associated enhancer-promoter interactions, chromatin and transcriptional state, and transgenic enhancer assays. We identified TF-cREs modules with distinct chromatin features and enhancer activity that have complementary roles driving GABAergic neurogenesis and suppressing other developmental fates. While the majority of distal cREs were bound by one or two TFs, a small proportion were extensively bound, and these enhancers also exhibited exceptional evolutionary conservation, motif density, and complex chromosomal interactions. Our results provide new insights into how modules of combinatorial TF-cRE interactions activate and repress developmental expression programs and demonstrate the value of TF binding data in modeling gene regulatory wiring.

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