RESUMEN
Cortical arealization arises during neurodevelopment from the confluence of molecular gradients representing patterned expression of morphogens and transcription factors. However, whether similar gradients are maintained in the adult brain remains unknown. Here, we uncover three axes of topographic variation in gene expression in the adult human brain that specifically capture previously identified rostral-caudal, dorsal-ventral, and medial-lateral axes of early developmental patterning. The interaction of these spatiomolecular gradients i) accurately reconstructs the position of brain tissue samples, ii) delineates known functional territories, and iii) can model the topographical variation of diverse cortical features. The spatiomolecular gradients are distinct from canonical cortical axes differentiating the primary sensory cortex from the association cortex, but radiate in parallel with the axes traversed by local field potentials along the cortex. We replicate all three molecular gradients in three independent human datasets as well as two nonhuman primate datasets and find that each gradient shows a distinct developmental trajectory across the lifespan. The gradients are composed of several well-known transcription factors (e.g., PAX6 and SIX3), and a small set of genes shared across gradients are strongly enriched for multiple diseases. Together, these results provide insight into the developmental sculpting of functionally distinct brain regions, governed by three robust transcriptomic axes embedded within brain parenchyma.
Asunto(s)
Encéfalo , Humanos , Encéfalo/metabolismo , Animales , Adulto , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Factor de Transcripción PAX6/metabolismo , Factor de Transcripción PAX6/genética , Regulación del Desarrollo de la Expresión Génica , Masculino , Tipificación del Cuerpo/genética , Femenino , Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/genéticaRESUMEN
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.
Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Corteza Cerebral , Receptores ErbB , Proteínas Hedgehog , Proteínas del Tejido Nervioso , Células-Madre Neurales , Neurogénesis , Factor de Transcripción 2 de los Oligodendrocitos , Factor de Transcripción PAX6 , Animales , Neurogénesis/fisiología , Corteza Cerebral/metabolismo , Corteza Cerebral/citología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Receptores ErbB/metabolismo , Receptores ErbB/genética , Ratones , Factor de Transcripción 2 de los Oligodendrocitos/metabolismo , Factor de Transcripción 2 de los Oligodendrocitos/genética , Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas Hedgehog/metabolismo , Proteínas Hedgehog/genética , Factor de Transcripción PAX6/metabolismo , Factor de Transcripción PAX6/genética , Células-Madre Neurales/metabolismo , Células-Madre Neurales/citología , Proteínas de Homeodominio/metabolismo , Proteínas de Homeodominio/genética , Proteína Gli3 con Dedos de Zinc/metabolismo , Proteína Gli3 con Dedos de Zinc/genética , Proteínas del Ojo/metabolismo , Proteínas del Ojo/genética , Proteínas Represoras/metabolismo , Proteínas Represoras/genética , Factores de Transcripción Paired Box/metabolismo , Factores de Transcripción Paired Box/genética , Neuroglía/metabolismo , Neuroglía/citología , Regulación del Desarrollo de la Expresión Génica , Transducción de Señal , Bulbo Olfatorio/metabolismo , Bulbo Olfatorio/citología , Linaje de la Célula , HumanosRESUMEN
Nonsense and missense mutations in the transcription factor PAX6 cause a wide range of eye development defects, including aniridia, microphthalmia and coloboma. To understand how changes of PAX6:DNA binding cause these phenotypes, we combined saturation mutagenesis of the paired domain of PAX6 with a yeast one-hybrid (Y1H) assay in which expression of a PAX6-GAL4 fusion gene drives antibiotic resistance. We quantified binding of more than 2700 single amino-acid variants to two DNA sequence elements. Mutations in DNA-facing residues of the N-terminal subdomain and linker region were most detrimental, as were mutations to prolines and to negatively charged residues. Many variants caused sequence-specific molecular gain-of-function effects, including variants in position 71 that increased binding to the LE9 enhancer but decreased binding to a SELEX-derived binding site. In the absence of antibiotic selection, variants that retained DNA binding slowed yeast growth, likely because such variants perturbed the yeast transcriptome. Benchmarking against known patient variants and applying ACMG/AMP guidelines to variant classification, we obtained supporting-to-moderate evidence that 977 variants are likely pathogenic and 1306 are likely benign. Our analysis shows that most pathogenic mutations in the paired domain of PAX6 can be explained simply by the effects of these mutations on PAX6:DNA association, and establishes Y1H as a generalisable assay for the interpretation of variant effects in transcription factors.
Asunto(s)
ADN , Factor de Transcripción PAX6 , Factor de Transcripción PAX6/genética , Factor de Transcripción PAX6/metabolismo , Humanos , ADN/genética , ADN/metabolismo , Sitios de Unión , Unión Proteica , Mutación , Técnicas del Sistema de Dos Híbridos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Mutación Missense , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Análisis Mutacional de ADNRESUMEN
Pax6 is a critical transcription factor involved in the development of the central nervous system. However, in humans, mutations in Pax6 predominantly result in iris deficiency rather than neurological phenotypes. This may be attributed to the distinct functions of Pax6 isoforms, Pax6a and Pax6b. In this study, we investigated the spatial and temporal expression patterns of Pax6 isoforms during different stages of mouse eye development. We observed a strong correlation between Pax6a expression and the neuroretina gene Sox2, while Pax6b showed a high correlation with iris-component genes, including the mesenchymal gene Foxc1. During early patterning from E10.5, Pax6b was expressed in the hinge of the optic cup and neighboring mesenchymal cells, whereas Pax6a was absent in these regions. At E14.5, both Pax6a and Pax6b were expressed in the future iris and ciliary body, coinciding with the integration of mesenchymal cells and Mitf-positive cells in the outer region. From E18.5, Pax6 isoforms exhibited distinct expression patterns as lineage genes became more restricted. To further validate these findings, we utilized ESC-derived eye organoids, which recapitulated the temporal and spatial expression patterns of lineage genes and Pax6 isoforms. Additionally, we found that the spatial expression patterns of Foxc1 and Mitf were impaired in Pax6b-mutant ESC-derived eye organoids. This in vitro eye organoids model suggested the involvement of Pax6b-positive local mesodermal cells in iris development. These results provide valuable insights into the regulatory roles of Pax6 isoforms during iris and neuroretina development and highlight the potential of ESC-derived eye organoids as a tool for studying normal and pathological eye development.
Asunto(s)
Ojo , Regulación del Desarrollo de la Expresión Génica , Organoides , Factor de Transcripción PAX6 , Isoformas de Proteínas , Factor de Transcripción PAX6/genética , Factor de Transcripción PAX6/metabolismo , Animales , Ratones , Organoides/metabolismo , Organoides/crecimiento & desarrollo , Organoides/citología , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Ojo/crecimiento & desarrollo , Ojo/metabolismo , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Organogénesis/genéticaRESUMEN
The role extracellular matrix (ECM) in multiple events of morphogenesis has been well described, little is known about its specific role in early eye development. One of the first morphogenic events in lens development is placodal thickening, which converts the presumptive lens ectoderm from cuboidal to pseudostratified epithelium. This process occurs in the anterior pre-placodal ectoderm when the optic vesicle approaches the cephalic ectoderm and is regulated by transcription factor Pax6 and secreted BMP4. Since cells and ECM have a dynamic relationship of interdependence and modulation, we hypothesized that the ECM evolves with cell shape changes during lens placode formation. This study investigates changes in optic ECM including both protein distribution deposition, extracellular gelatinase activity and gene expression patterns during early optic development using chicken and mouse models. In particular, the expression of Timp2, a metalloprotease inhibitor, corresponds with a decrease in gelatinase activity within the optic ECM. Furthermore, we demonstrate that optic ECM remodeling depends on BMP signaling in the placode. Together, our findings suggest that the lens placode plays an active role in remodeling the optic ECM during early eye development.
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Matriz Extracelular , Regulación del Desarrollo de la Expresión Génica , Cristalino , Factor de Transcripción PAX6 , Animales , Matriz Extracelular/metabolismo , Ratones , Cristalino/metabolismo , Cristalino/crecimiento & desarrollo , Cristalino/citología , Factor de Transcripción PAX6/metabolismo , Factor de Transcripción PAX6/genética , Proteínas del Ojo/metabolismo , Proteínas del Ojo/genética , Proteína Morfogenética Ósea 4/metabolismo , Proteína Morfogenética Ósea 4/genética , Embrión de Pollo , Proteínas de Homeodominio/metabolismo , Proteínas de Homeodominio/genética , Inhibidor Tisular de Metaloproteinasa-2/metabolismo , Inhibidor Tisular de Metaloproteinasa-2/genética , Factores de Transcripción Paired Box/metabolismo , Factores de Transcripción Paired Box/genética , Proteínas Represoras/metabolismo , Proteínas Represoras/genética , Transducción de Señal , Pollos/genética , Ojo/metabolismo , Ojo/crecimiento & desarrollo , Ojo/embriologíaRESUMEN
BACKGROUND: Corneal injuries, often leading to severe vision loss or blindness, have traditionally been treated with the belief that limbal stem cells (LSCs) are essential for repair and homeostasis, while central corneal epithelial cells (CCECs) were thought incapable of such repair. However, our research reveals that CCECs can fully heal and maintain the homeostasis of injured corneas in rats, even without LSCs. We discovered that CXCL14, under PAX6's influence, significantly boosts the stemness, proliferation, and migration of CCECs, facilitating corneal wound healing and homeostasis. This finding introduces CXCL14 as a promising new drug target for corneal injury treatment. METHODS: To investigate the PAX6/CXCL14 regulatory axis's role in CCECs wound healing, we cultured human corneal epithelial cell lines with either increased or decreased expression of PAX6 and CXCL14 using adenovirus transfection in vitro. Techniques such as coimmunoprecipitation, chromatin immunoprecipitation, immunofluorescence staining, western blot, real-time PCR, cell colony formation, and cell cycle analysis were employed to validate the axis's function. In vivo, a rat corneal epithelial injury model was developed to further confirm the PAX6/CXCL14 axis's mechanism in repairing corneal damage and maintaining corneal homeostasis, as well as to assess the potential of CXCL14 protein as a therapeutic agent for corneal injuries. RESULTS: Our study reveals that CCECs naturally express high levels of CXCL14, which is significantly upregulated by PAX6 following corneal damage. We identified SDC1 as CXCL14's receptor, whose engagement activates the NF-κB pathway to stimulate corneal repair by enhancing the stemness, proliferative, and migratory capacities of CCECs. Moreover, our research underscores CXCL14's therapeutic promise for corneal injuries, showing that recombinant CXCL14 effectively accelerates corneal healing in rat models. CONCLUSION: CCECs play a critical and independent role in the repair of corneal injuries and the maintenance of corneal homeostasis, distinct from that of LSCs. The PAX6/CXCL14 regulatory axis is pivotal in this process. Additionally, our research demonstrates that the important function of CXCL14 in corneal repair endows it with the potential to be developed into a novel therapeutic agent for treating corneal injuries.
Asunto(s)
Proliferación Celular , Quimiocinas CXC , Lesiones de la Cornea , Epitelio Corneal , Factor de Transcripción PAX6 , Cicatrización de Heridas , Animales , Humanos , Masculino , Ratas , Línea Celular , Movimiento Celular , Quimiocinas CXC/metabolismo , Quimiocinas CXC/genética , Lesiones de la Cornea/metabolismo , Lesiones de la Cornea/patología , Células Epiteliales/metabolismo , Epitelio Corneal/patología , Epitelio Corneal/metabolismo , Factor de Transcripción PAX6/metabolismo , Factor de Transcripción PAX6/genética , Ratas Sprague-DawleyRESUMEN
Phenotypic and genotypic heterogeneity in congenital ocular diseases, especially in anterior segment dysgenesis (ASD), have created challenges for proper diagnosis and classification of diseases. Over the last decade, genomic research has indeed boosted our understanding in the molecular basis of ASD and genes associated with both autosomal dominant and recessive patterns of inheritance have been described with a wide range of expressivity. Here we describe the molecular characterization of a cohort of 162 patients displaying isolated or syndromic congenital ocular dysgenesis. Samples were analyzed with diverse techniques, such as direct sequencing, multiplex ligation-dependent probe amplification, and whole exome sequencing (WES), over 20 years. Our data reiterate the notion that PAX6 alterations are primarily associated with ASD, mostly aniridia, since the majority of the cohort (66.7%) has a pathogenic or likely pathogenic variant in the PAX6 locus. Unexpectedly, a high fraction of positive samples (20.3%) displayed deletions involving the 11p13 locus, either partially/totally involving PAX6 coding region or abolishing its critical regulatory region, underlying its significance. Most importantly, the use of WES has allowed us to both assess variants in known ASD genes (i.e., CYP1B1, ITPR1, MAB21L1, PXDN, and PITX2) and to identify rarer phenotypes (i.e., MIDAS, oculogastrointestinal-neurodevelopmental syndrome and Jacobsen syndrome). Our data clearly suggest that WES allows expanding the analytical portfolio of ocular dysgenesis, both isolated and syndromic, and that is pivotal for the differential diagnosis of those conditions in which there may be phenotypic overlaps and in general in ASD.
Asunto(s)
Secuenciación del Exoma , Factor de Transcripción PAX6 , Humanos , Factor de Transcripción PAX6/genética , Masculino , Femenino , Anomalías del Ojo/genética , Anomalías del Ojo/diagnóstico , Anomalías del Ojo/patología , Fenotipo , Segmento Anterior del Ojo/anomalías , Segmento Anterior del Ojo/patología , Mutación , Oftalmopatías/genética , Oftalmopatías/diagnóstico , Oftalmopatías/congénitoRESUMEN
The conjunctiva is a non-keratinized, stratified columnar epithelium with characteristics different from the cornea and eyelid epidermis. From development to adulthood, a distinguishing feature of ocular versus epidermal epithelia is the expression of the master regulator PAX6. A conditionally immortalized conjunctival epithelial cell line (iHCjEC) devoid of stromal or immune cells established in our laboratory spontaneously manifested epidermal metaplasia and upregulated expression of the keratinization-related genes SPRR1A/B and the epidermal cytokeratins KRT1 and KRT10 at the expense of the conjunctival trait. In addition, iHCjEC indicated a significant decrease in PAX6 expression. Dry eye syndrome (DES) and severe ocular surface diseases, such as Sjögren's syndrome and Stevens-Johnson syndrome, cause the keratinization of the entire ocular surface epithelia. We used iHCjECs as a conjunctiva epidermal metaplasia model to test PAX6, serum, and glucocorticoid interventions. Reintroducing PAX6 to iHCjECs resulted in upregulating genes related to cell adhesion and tight junctions, including MIR200CHG and CLDN1. The administration of glucocorticoids or serum resulted in the downregulation of epidermal genes (DSG1, SPRR1A/B, and KRT1) and partially corrected epidermal metaplasia. Our results using an isolated conjunctival epidermal metaplasia model point toward the possibility of rationally "repurposing" clinical interventions, such as glucocorticoid, serum, or PAX6 administration, for treating epidermal metaplasia of the conjunctiva.
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Conjuntiva , Metaplasia , Conjuntiva/patología , Conjuntiva/metabolismo , Factor de Transcripción PAX6/genética , Factor de Transcripción PAX6/metabolismo , Humanos , Células Epiteliales/metabolismo , Células Epiteliales/patología , Glucocorticoides/uso terapéutico , Regulación de la Expresión Génica , Epidermis/patología , Epidermis/metabolismo , Animales , Reacción en Cadena en Tiempo Real de la Polimerasa , Línea CelularRESUMEN
BACKGROUND: Aniridia is a rare eye disorder with a high incidence of glaucoma, and surgical intervention is often needed to control the intraocular pressure (IOP). Here, we reported a case of illuminated microcatheter-assisted circumferential trabeculotomy (MAT) performed on an aniridic glaucoma patient following a previous failed angle surgery. The surgical procedures for aniridic glaucoma were also reviewed. CASE PRESENTATION: A 21-year-old man, diagnosed with aniridic glaucoma, came to our hospital consulting for the poor control of left eye's IOP despite receiving goniotomy surgery 3 years ago. The IOP was 26 mmHg with maximum topical antiglaucoma eyedrops. The central cornea was opaque and the majority of iris was absent. The gonioscopy and ultrasound biomicroscopy (UBM) demonstrated that 360° anterior chamber angle was closed. The whole exome sequencing of peripheral blood confirmed a 13.39 Mb copy number loss at chromosome 11p15.1p13, containing PAX6 and WT1 gene. The 360° MAT surgery was performed on his left eye. At 1-year follow-up, the IOP was 19mmHg with 2 kinds of topical antiglaucoma medications, and the postoperative UBM demonstrated the successful incision of the anterior chamber angle. CONCLUSIONS: The case presented here exhibited a case of aniridic glaucoma treated by MAT surgery. The MAT surgery may be an effective option for IOP control in aniridic glaucoma patients following a previous failed angle surgery.
Asunto(s)
Aniridia , Glaucoma , Trabeculectomía , Humanos , Masculino , Adulto Joven , Estudios de Seguimiento , Glaucoma/diagnóstico , Glaucoma/cirugía , Gonioscopía , Presión Intraocular , Factor de Transcripción PAX6 , Estudios Retrospectivos , Trabeculectomía/métodos , Resultado del TratamientoRESUMEN
The PAX6 gene encodes a highly-conserved transcription factor involved in eye development. Heterozygous loss-of-function variants in PAX6 can cause a range of ophthalmic disorders including aniridia. A key molecular diagnostic challenge is that many PAX6 missense changes are presently classified as variants of uncertain significance. While computational tools can be used to assess the effect of genetic alterations, the accuracy of their predictions varies. Here, we evaluated and optimised the performance of computational prediction tools in relation to PAX6 missense variants. Through inspection of publicly available resources (including HGMD, ClinVar, LOVD and gnomAD), we identified 241 PAX6 missense variants that were used for model training and evaluation. The performance of ten commonly used computational tools was assessed and a threshold optimization approach was utilized to determine optimal cut-off values. Validation studies were subsequently undertaken using PAX6 variants from a local database. AlphaMissense, SIFT4G and REVEL emerged as the best-performing predictors; the optimized thresholds of these tools were 0.967, 0.025, and 0.772, respectively. Combining the prediction from these top-three tools resulted in lower performance compared to using AlphaMissense alone. Tailoring the use of computational tools by employing optimized thresholds specific to PAX6 can enhance algorithmic performance. Our findings have implications for PAX6 variant interpretation in clinical settings.
Asunto(s)
Mutación Missense , Factor de Transcripción PAX6 , Factor de Transcripción PAX6/genética , Factor de Transcripción PAX6/metabolismo , Humanos , Biología Computacional/métodos , Programas InformáticosRESUMEN
PURPOSE: A large number of epidemiological studies have shown that myopia is a complex disease involving genetic, environmental, and behavioral factors. The purpose of this study was to explore the role of PAX6 gene methylation in myopia in Chinese adolescents. METHODS: Eighty junior high school students were divided into four groups based on their vision test results: mild myopia, moderate myopia, severe myopia, and non-myopia control. The methylation level of PAX6 gene promoter was detected by bisulfate pyrosequencing. RESULTS: The methylation level of PAX6 gene in myopia group (8.06% ± 1.43%) was slightly but significantly higher than that in non-myopia controls (7.26% ± 1.17%). In addition, PAX6 gene methylation levels presented a decreasing pattern along with the aggravation of myopia. Post-hoc analysis indicated significant inter-group differences for the mild myopia group and other groups (All p < .05). In the subgroup analysis by gender, the methylation level of PAX6 gene promoter in girls was higher than that in boys (p = .023). The ROC curves showed a high accuracy of PAX6 gene methylation to predict mild myopia (AUC (95% CI) = 0.828 (0.709-0.947), p < .001). CONCLUSIONS: The methylation of PAX6 gene might play a role in the onset and progression of myopia in Chinese adolescents. And this could potentially explore the potential molecular mechanisms of juvenile myopia in the future.
Asunto(s)
Metilación de ADN , Miopía , Factor de Transcripción PAX6 , Regiones Promotoras Genéticas , Adolescente , Niño , Femenino , Humanos , Masculino , China/epidemiología , Pueblos del Este de Asia/genética , Miopía/genética , Factor de Transcripción PAX6/genética , Proyectos PilotoRESUMEN
Aniridia is an autosomal dominant condition characterized by the complete or partial absence of the iris, often with additional presentations such as foveal hypoplasia, nystagmus, cataract, glaucoma and other ocular abnormalities. Most cases are caused by heterozygous mutations in the paired box 6 gene (PAX6), which codes for a transcription factor that regulates eye development. Four patients from our hospital who presented with ocular phenotypes were recruited for research sequencing with informed consent. Sanger sequencing of PAX6 coding exons or exome sequencing was performed on genomic DNA from venous blood samples. Variants in PAX6 were identified in the four patients. Two variants are recurrent single-nucleotide substitutions - one is a substitution found in a patient with bilateral aniridia, whereas the other is a splice variant in a patient with nystagmus and neuroblastoma. The other two variants are novel and found in two patients with isolated aniridia. Both are small duplications that are predicted to lead to premature termination. For the recurrent variants, the comparison of phenotypes for patients with identical variants would shed light on the mechanisms of pathogenesis, and the discovery of two novel variants expands the spectrum of PAX6 mutations.
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Aniridia , Catarata , Humanos , Cara , Aniridia/genética , Catarata/genética , Exones , Asia Sudoriental , Factor de Transcripción PAX6/genéticaRESUMEN
The functions of non-coding regulatory elements (NCREs), which constitute a major fraction of the human genome, have not been systematically studied. Here we report a method involving libraries of paired single-guide RNAs targeting both ends of an NCRE as a screening system for the Cas9-mediated deletion of thousands of NCREs genome-wide to study their functions in distinct biological contexts. By using K562 and 293T cell lines and human embryonic stem cells, we show that NCREs can have redundant functions, and that many ultra-conserved elements have silencer activity and play essential roles in cell growth and in cellular responses to drugs (notably, the ultra-conserved element PAX6_Tarzan may be critical for heart development, as removing it from human embryonic stem cells led to defects in cardiomyocyte differentiation). The high-throughput screen, which is compatible with single-cell sequencing, may allow for the identification of druggable NCREs.
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Sistemas CRISPR-Cas , ARN Guía de Sistemas CRISPR-Cas , Humanos , ARN Guía de Sistemas CRISPR-Cas/genética , Células K562 , Sistemas CRISPR-Cas/genética , Células HEK293 , Genoma Humano/genética , Diferenciación Celular/genética , Miocitos Cardíacos/metabolismo , ARN no Traducido/genética , Células Madre Embrionarias Humanas/metabolismo , Factor de Transcripción PAX6/genética , Factor de Transcripción PAX6/metabolismo , Biblioteca de GenesRESUMEN
Purpose: N6-methyladenosine (m6A) methylation is a chemical modification that occurs on RNA molecules, where the hydrogen atom of adenine (A) nucleotides is replaced by a methyl group, forming N6-methyladenosine. This modification is a dynamic and reversible process that plays a crucial role in regulating various biological processes, including RNA stability, transport, translation, and degradation. Currently, there is a lack of research on the role of m6A modifications in maintaining the characteristics of RPE cells. m6A readers play a crucial role in executing the functions of m6A modifications, which prompted our investigation into their regulatory roles in the RPE. Methods: Phagocytosis assays, immunofluorescence staining, flow cytometry experiments, ß-galactosidase staining, and RNA sequencing (RNA-seq) were conducted to assess the functional and cellular characteristics changes in retinal pigment epithelium (RPE) cells following short-hairpin RNA-mediated knockdown of insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2). RNA-seq and ultraviolet crosslinking immunoprecipitation with high-throughput sequencing (HITS-CLIP) were employed to identify the target genes regulated by IGF2BP2. adeno-associated virus (AAV) subretinal injection was performed in 6- to 8-week-old C57 mice to reduce IGF2BP2 expression in the RPE, and the impact of IGF2BP2 knockdown on mouse visual function was assessed using immunofluorescence, quantitative real-time PCR, optical coherence tomography, and electroretinography. Results: IGF2BP2 was found to have a pronounced effect on RPE phagocytosis. Subsequent in-depth exploration revealed that IGF2BP2 modulates the mRNA stability of PAX6 and OTX2, and the loss of IGF2BP2 induces inflammatory and aging phenotypes in RPE cells. IGF2BP2 knockdown impaired RPE function, leading to retinal dysfunction in vivo. Conclusions: Our data suggest a crucial role of IGF2BP2 as an m6A reader in maintaining RPE homeostasis by regulating the stability of PAX6 and OTX2, making it a potential target for preventing the occurrence of retinal diseases related to RPE malfunction.
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Factores de Transcripción Otx , Factor de Transcripción PAX6 , Proteínas de Unión al ARN , Epitelio Pigmentado de la Retina , Animales , Ratones , Células Cultivadas , Electrorretinografía , Citometría de Flujo , Regulación de la Expresión Génica/fisiología , Homeostasis , Ratones Endogámicos C57BL , Factores de Transcripción Otx/metabolismo , Factores de Transcripción Otx/genética , Factor de Transcripción PAX6/genética , Factor de Transcripción PAX6/metabolismo , Fagocitosis/fisiología , Epitelio Pigmentado de la Retina/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Tomografía de Coherencia ÓpticaRESUMEN
BACKGROUND: Neuroendocrine prostate cancer (NEPC) is a lethal subset of prostate cancer which is characterized by neuroendocrine differentiation and loss of androgen receptor (AR) signaling. Growing evidence reveals that cell lineage plasticity is crucial in the failure of NEPC therapies. Although studies suggest the involvement of the neural transcription factor PAX6 in drug resistance, its specific role in NEPC remains unclear. METHODS: The expression of PAX6 in NEPC was identified via bioinformatics and immunohistochemistry. CCK8 assay, colony formation assay, tumorsphere formation assay and apoptosis assay were used to illustrate the key role of PAX6 in the progression of in vitro. ChIP and Dual-luciferase reporter assays were conducted to confirm the binding sequences of AR in the promoter region of PAX6, as well as the binding sequences of PAX6 in the promoter regions of STAT5A and MET. For in vivo validation, the xenograft model representing NEPC subtype underwent pathological analysis to verify the significant role of PAX6 in disease progression. Complementary diagnoses were established through public clinical datasets and transcriptome sequencing of specific cell lines. ATAC-seq was used to detect the chromatin accessibility of specific cell lines. RESULTS: PAX6 expression was significantly elevated in NEPC and negatively regulated by AR signaling. Activation of PAX6 in non-NEPC cells led to NE trans-differentiation, while knock-down of PAX6 in NEPC cells inhibited the development and progression of NEPC. Importantly, loss of AR resulted in an enhanced expression of PAX6, which reprogramed the lineage plasticity of prostate cancer cells to develop NE phenotypes through the MET/STAT5A signaling pathway. Through ATAC-seq, we found that a high expression level of PAX6 elicited enhanced chromatin accessibility, mainly through attenuation of H4K20me3, which typically causes chromatin silence in cancer cells. CONCLUSION: This study reveals a novel neural transcription factor PAX6 could drive NEPC progression and suggest that it might serve as a potential therapeutic target for the management of NEPC.
Asunto(s)
Cromatina , Factor de Transcripción PAX6 , Neoplasias de la Próstata , Factor de Transcripción STAT5 , Animales , Humanos , Masculino , Ratones , Línea Celular Tumoral , Cromatina/metabolismo , Cromatina/genética , Regulación Neoplásica de la Expresión Génica , Factor de Transcripción PAX6/metabolismo , Factor de Transcripción PAX6/genética , Fenotipo , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/genética , Transducción de Señal , Factor de Transcripción STAT5/metabolismo , Factor de Transcripción STAT5/genética , Proteínas Proto-Oncogénicas c-met/genética , Proteínas Proto-Oncogénicas c-met/metabolismoRESUMEN
Impaired brain glucose metabolism is an early indicator of Alzheimer's disease (AD); however, the fundamental mechanism is unknown. In this study, we found a substantial decline in isocitrate dehydrogenase 3ß (IDH3ß) levels, a critical tricarboxylic acid cycle enzyme, in AD patients and AD-transgenic mice's brains. Further investigations demonstrated that the knockdown of IDH3ß induced oxidation-phosphorylation uncoupling, leading to reduced energy metabolism and lactate accumulation. The resulting increased lactate, a source of lactyl, was found to promote histone lactylation, thereby enhancing the expression of paired-box gene 6 (PAX6). As an inhibitory transcription factor of IDH3ß, the elevated PAX6 in turn inhibited the expression of IDH3ß, leading to tau hyperphosphorylation, synapse impairment, and learning and memory deficits resembling those seen in AD. In AD-transgenic mice, upregulating IDH3ß and downregulating PAX6 were found to improve cognitive functioning and reverse AD-like pathologies. Collectively, our data suggest that impaired oxidative phosphorylation accelerates AD progression via a positive feedback inhibition loop of IDH3ß-lactate-PAX6-IDH3ß. Breaking this loop by upregulating IDH3ß or downregulating PAX6 attenuates AD neurodegeneration and cognitive impairments.
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Enfermedad de Alzheimer , Isocitrato Deshidrogenasa , Factor de Transcripción PAX6 , Animales , Femenino , Humanos , Masculino , Ratones , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/metabolismo , Retroalimentación Fisiológica , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/metabolismo , Ratones Transgénicos , Factor de Transcripción PAX6/genética , Factor de Transcripción PAX6/metabolismoRESUMEN
BACKGROUND: The limited regenerative capacity of damaged neurons in adult mammals severely restricts neural repair. Although stem cell transplantation is promising, its clinical application remains challenging. Direct reprogramming, which utilizes cell plasticity to regenerate neurons, is an emerging alternative approach. METHODS: We utilized primary postnatal cortical astrocytes for reprogramming induced neurons (iNs) through the viral-mediated overexpression of the transcription factors Ngn2 and Pax6 (NP). Fluorescence-activated cell sorting (FACS) was used to enrich successfully transfected cells, followed by single-cell RNA sequencing (scRNA-seq) using the 10 × Genomics platform for comprehensive transcriptomic analysis. RESULTS: The scRNA-seq revealed that NP overexpression led to the differentiation of astrocytes into iNs, with percentages of 36% and 39.3% on days 4 and 7 posttransduction, respectively. CytoTRACE predicted the developmental sequence, identifying astrocytes as the reprogramming starting point. Trajectory analysis depicted the dynamic changes in gene expression during the astrocyte-to-iN transition. CONCLUSIONS: This study elucidates the molecular dynamics underlying astrocyte reprogramming into iNs, revealing key genes and pathways involved in this process. Our research contributes novel insights into the molecular mechanisms of NP-mediated reprogramming, suggesting avenues for optimizing the efficiency of the reprogramming process.
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Astrocitos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Reprogramación Celular , Proteínas del Tejido Nervioso , Factor de Transcripción PAX6 , Análisis de la Célula Individual , Astrocitos/metabolismo , Animales , Reprogramación Celular/genética , Factor de Transcripción PAX6/genética , Factor de Transcripción PAX6/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Análisis de la Célula Individual/métodos , Ratones , Diferenciación Celular/genética , Linaje de la Célula/genética , Neuronas/metabolismo , Células CultivadasRESUMEN
Colorectal cancer is a cancer that arises from the abnormal growth of cells in the colon or rectum. Osteosarcoma (OS) is a common primary bone tumor with high degree of malignancy. The configuration files for colorectal cancer dataset GSE142279 and OS datasets GSE197158 and GSE206448 were downloaded from Gene Expression Omnibus database using the platforms GPL20795, GPL20301, and GPL24676. Differentially expressed genes (DEGs) were screened and weighted gene co-expression network analysis (WGCNA) was performed. Construction and analysis of protein-protein interactions (PPI) network. Functional enrichment analysis, gene set enrichment analysis (GSEA) were performed. A heat map of gene expression was drawn. The Comparative Toxicogenomics Database (CTD) was used to find the diseases most associated with the core genes. TargetScan was used to screen miRNAs regulating DEGs. According to the Gene Ontology (GO) analysis, DEGs are mainly enriched in acetylcholine binding receptor activity involved in Wnt signaling pathway, cell polarity pathway, PI3K-Akt signaling pathway, receptor regulator activity, cytokine-cytokine receptor interaction, transcriptional misregulation in cancer, and inflammation-mediated regulation of tryptophan transport. In the Metascape enrichment analysis, GO enrichment items related to the regulation of Wnt signaling pathway, regulation of muscle system process, and regulation of actin filament-based movement. Eight core genes (CUX1, NES, BCL11B, PAX6, EMX1, MCOLN2, TRPA1, TRPC4) were identified. CTD showed that 4 genes (CUX1, EMX1, TRPA1, BCL11B) were associated with colorectal neoplasms, colorectal tumors, colonic diseases, multiple myeloma, OS, and inflammation. PAX6, TRPA1, BCL11B, MCOLN2, CUX1, and EMX1 are highly expressed in colorectal cancer and OS, and the higher the expression level, the worse the prognosis.
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Neoplasias Óseas , Neoplasias Colorrectales , Proteínas de Homeodominio , Osteosarcoma , Factor de Transcripción PAX6 , Humanos , Fosfatidilinositol 3-Quinasas/metabolismo , Perfilación de la Expresión Génica , Factores de Transcripción/genética , Osteosarcoma/patología , Neoplasias Óseas/patología , Neoplasias Colorrectales/genética , Inflamación/genética , Proteínas Supresoras de Tumor/genética , Biología Computacional , Redes Reguladoras de Genes , Regulación Neoplásica de la Expresión Génica , Canal Catiónico TRPA1/genética , Proteínas Represoras/metabolismoRESUMEN
Remifentanilinduced hyperalgesia (RIH) is characterized by the emergence of stimulationinduced pain, including phenomena such as allodynia and thermal hyperalgesia following remifentanil infusion. As a sequencespecific DNA binding transcription factor, PAX6 positively and negatively regulates transcription and is expressed in multiple cell types in the developing and adult central nervous system. It was hypothesized that puerarin could relieve RIH via targeting PAX6 to regulate transcription of transient receptor potential cation channel subfamily V Member 1 (TRPV1). A total of 32 rats were randomly divided into five groups, namely control group, RI group, RI + 10 mg/kg puerarin group (RI + puerarin10), RI + 20 mg/kg puerarin group (RI + puerarin20), and RI + 40 mg/kg puerarin group (RI + puerarin40). Mechanical and thermal hyperalgesia were tested at 24, 2, 6, 24 and 48 h after remifentanil infusion. Following the sacrifice of rats after the last behavioral test, western blot was used to detect the expression levels of TRPV1 in the tissues; Immunofluorescence staining and western blotting were used to detect the expression of PAX6 in the spinal cord. PharmMapper and JASPAR were used to predict the binding sites of puerarin/PAX6/TRPV1. Chromatin immunoprecipitationPCR and dual luciferase reporter assay were used to verify the targeting relationship between PAX6 and TRPV1. Immunofluorescence was used to detect the expression levels of TRPV1 and pNR2B. The results revealed that puerarin (10, 20, 40 mg/kg) dosedependently reduced thermal and mechanical hyperalgesia from 2 to 48 h after remifentanil infusion. Remifentanil infusion remarkably stimulated the expression of phosphorylated (p)NR2B. Nevertheless, the increased amount of pNR2B by RIH was dosedependently suppressed by puerarin in rats. In conclusion, puerarin was revealed to attenuate postoperative RIH via targeting PAX6 to regulate the transcription of TRPV1.
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Hiperalgesia , Isoflavonas , Animales , Ratas , Hiperalgesia/inducido químicamente , Hiperalgesia/tratamiento farmacológico , Hiperalgesia/genética , Isoflavonas/farmacología , Isoflavonas/uso terapéutico , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/etiología , Piperidinas/farmacología , Ratas Sprague-Dawley , Remifentanilo/efectos adversos , Factor de Transcripción PAX6/efectos de los fármacos , Factor de Transcripción PAX6/metabolismo , Canales Catiónicos TRPV/efectos de los fármacos , Canales Catiónicos TRPV/genética , Canales Catiónicos TRPV/metabolismoRESUMEN
Abstract Objective: We aimed to describe the clinical and phenotypic manifestations as well as the visual prognosis of a family with CA in Northeastern Brazil. Methods: This was a cross-sectional study involving 31 individuals (56 eyes) from the same family presenting CA phenotypes. The study population resided in the municipality of Água Branca, in the backlands of the state of Alagoas, Northeastern Brazil. The clinical and phenotypic variables were analyzed. For the analysis, descriptive statistics (absolute and relative frequency and measures of central tendency and dispersion) and inferential statistics (Shapiro-Wilk and Student's t tests) were used, with 95% confidence intervals and significance set at 5%. Results: Of the 31 individuals, 18 (58.1%) were male, with a mean age of 27.45 ± 17.49 years, with no difference between sexes. Of the 56 eyes evaluated, 26 and 30 were right and left eyes, respectively; 61.3% (n = 19) individuals had complete bilateral aniridia and 25.8% (n = 8) reported a total loss of light perception in both the eyes. The most prevalent ocular abnormalities were nystagmus (n = 27; 87.09%), cataract (n = 20; 64.5%), strabismus (n = 14; 45.2%), corneal changes such as opacities and/or vascularization (n = 13; 41.93%), and ectopia lentis (n = 6; 19.4%). Further, 13 individuals underwent retinal optical coherence tomography, six man and seven women aged 9-48 (mean, 30.15 ± 15.9) years. All patients presented absence of foveal depression as well as reduced macular thickness and visual acuity. Nine subjects underwent phacoemulsification. Conclusion: The study showed wide phenotypic variation among the studied individuals, with poor visual prognosis. The study highlights the need to establish comprehensive care mechanisms for families with the disease.
Resumo Objetivo: Descrever manifestações clínicas e fenotípicas e o prognóstico visual de uma família com aniridia congênita (AC). Métodos: Trata-se de estudo transversal envolvendo 31 indivíduos (56 olhos), de uma mesma família com fenótipo de AC residindo no município de Água Branca, no sertão do estado de Alagoas, região nordeste do Brasil. Foram analisadas variáveis clínicas e fenotípicas. Para a análise, foi utilizada a estatística descritiva (frequência absoluta e relativa e medidas de tendência central e de dispersão) e inferencial (testes de Shapiro-Wilk e t Student). Considerou-se o intervalo de confiança de 95% e a significância de 5%. Resultados: Dos 31 indivíduos, 18 (58,1%) eram do sexo masculino, com média de idade de 27,45±17,49, sem diferença entre os sexos. Dos 56 olhos avaliados, 26 eram olhos direitos e 30 olhos esquerdos: 61,3% (n=19) apresentavam aniridia bilateral total; 25,8% (n=8) referiam perda total de percepção da luz em ambos os olhos. As anormalidades oculares mais prevalentes foram o nistagmo (n=27; 87,09%), catarata (n=20; 64,5%), estrabismo 14 (45,2%), alterações opacidades ou vascularização corneanas (n=13; 41,93%) e ectopia lentis (n=6; 19,4%). Os 13 indivíduos submetidos à tomografia de coerência óptica (OCT) retiniana apresentavam perda da depressão foveal, redução da espessura macular e redução da acuidade visual. Nove indivíduos foram submetidos a cirurgia de facoemulsificação. Conclusão: O estudo mostrou ampla variação fenotípica entre os indivíduos estudados, com pobre prognóstico visual. O estudo destaca a necessidade de estabelecer mecanismos de cuidado integral para as famílias com a doença.