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1.
Ultrasonics ; 141: 107321, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38663309

RESUMO

Far-field laser technology has greatly promoted the progress of nondestructive ultrasonic imaging of bulk structures. However, under thermoelastic excitation, the body waves exhibit a relatively low signal-to-noise ratio, resulting in images with low resolution and contrast. Based on the motivation, this paper developed a frequency-domain phase weighted imaging method to improve the quality of laser ultrasonic defect imaging. Firstly, laser ultrasonic scanning was performed on the sample with artificial transverse hole defects. The cylindrical lens focused line source was used to improve the intensity of the body wave signals, and ensure that there was no damage on the material surface under high laser energies. Then, the frequency-domain phase shift migration (PSM) algorithm was used to perform multimode imaging of defects, achieving frequency-domain synthetic aperture focusing technique (F-SAFT) and total focused method (F-TFM) imaging based on full matrix capture. Furthermore, the phase circular statistical vector (PCSV) was proposed for weighted optimization, which improved the image quality, suppressed the background noise and multimode artifacts. Finally, the imaging quality of several algorithms were discussed. The results indicate that frequency-domain images were superior to time-domain results. After phase weighting, the imaging quality can be further improved, and the detection blind zone was significantly reduced. This work will contribute to the rapid and high-quality defect imaging of laser ultrasonic.

2.
iScience ; 27(3): 109213, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38439953

RESUMO

Patients with Graves' disease (GD) can develop Graves' ophthalmopathy (GO), but the underlying pathological mechanisms driving this development remain unclear. In our study, which included patients with GD and GO, we utilized single-cell RNA sequencing (scRNA-seq) and multiplatform analyses to investigate CD169+ classical monocytes, which secrete proinflammatory cytokines and are expanded through activated interferon signaling. We found that CD169+ clas_mono was clinically significant in predicting GO progression and prognosis, and differentiated into CD169+ macrophages that promote inflammation, adipogenesis, and fibrosis. Our murine model of early-stage GO showed that CD169+ classical monocytes accumulated in orbital tissue via the Cxcl12-Cxcr4 axis. Further studies are needed to investigate whether targeting circulating monocytes and the Cxcl12-Cxcr4 axis could alleviate GO progression.

3.
Invest Ophthalmol Vis Sci ; 64(3): 30, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36943152

RESUMO

Purpose: Corneal epithelial homeostasis is maintained by coordinated gene expression across distinct cell populations, but the gene regulatory programs underlying this cellular diversity remain to be characterized. Here we applied single-cell multi-omics analysis to delineate the gene regulatory profile of mouse corneal epithelial cells under normal homeostasis. Methods: Single cells isolated from the cornea epithelium (with marginal conjunctiva) of adult mice were subjected to scRNA-seq and scATAC-seq using the 10×Genomics platform. Cell types were clustered by the graph-based visualization method uniform manifold approximation and projection and unbiased computational informatics analysis. The scRNA-seq and scATAC-seq datasets were integrated following the integration pipeline described in ArchR and Seurat. Results: We characterized diverse corneal epithelial cell types based on gene expression signatures and chromatin accessibility. We found that cell type-specific accessibility regions were mainly located at distal regions, suggesting essential roles of distal regulatory elements in determining corneal epithelial cell diversity. Trajectory analyses revealed a continuum of cell state transition and higher coordination between transcription factor (TF) motif accessibility and gene expression during corneal epithelial cell differentiation. By integrating transcriptomic and chromatin accessibility analysis, we identified cell type-specific and shared gene regulation programs. We also uncovered critical TFs driving corneal epithelial cell differentiation, such as nuclear factor I (NFI) family members, Rarg, Elf3. We found that nuclear factor-κB (NF-κB) family members were positive TFs in limbal cells and some superficial cells, but they were involved in regulating distinct biological processes. Conclusions: Our study presents a comprehensive gene regulatory landscape of mouse cornea epithelial cells, and provides valuable foundations for future investigation of corneal epithelial homeostasis in the context of cornea pathologies and regenerative medicine.


Assuntos
Sequenciamento de Cromatina por Imunoprecipitação , Análise da Expressão Gênica de Célula Única , Animais , Camundongos , Cromatina , Regulação da Expressão Gênica , Células Epiteliais
4.
Chinese Journal of School Health ; (12): 887-892, 2021.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-881370

RESUMO

Objective@#To explore the effects of group cognitive therapy on negative emotions and impulsivity among college students with Internet addiction.@*Methods@#33 college students with Internet addiction from one university in Guiyang were randomly divided into intervention group (n=16) and control group (n=17). Before and after the intervention, the Young s Internet Addiction Test, Self-rating Depression Scale,Self-rating Anxiety Scale and UPPSP Impulsive Behavior Scale were administered. In addition, the event-related potential (ERP) technology was used to detect the differences in EEG components related to impulse suppression between the two groups before and after the intervention.@*Results@#There were no statistically significant changes in the scores of Internet addiction, anxiety, depression, and impulsivity in the control group before and after(P>0.05); the N1 amplitude in the control group was higher than that in the previous test(t=-3.32, -3.19, P<0.05), and the changes in the amplitude of N2 and P3 were not statistically significant(P>0.05). The depression and anxiety scores of the intervention group were significantly lower than those of the pre-test (t=2.20, 2.45, P<0.05); the negative urgency and positive urgency scores were significantly lower than those of pre-test (t=3.84, 3.44, P<0.05); the N1 amplitude of the intervention group after treatment was higher than the previous test (t=-3.08, -2.72, P<0.05), and the N2 and P3 were lower than the previous test (t=2.10, 2.07, P<0.05).@*Conclusion@#Group cognitive therapy can improve the negative emotions of college students with Internet addiction, reduce the impulsivity level of college students with Internet addiction, and improve the impulse control function of college students with Internet addiction to a certain extent.

5.
FASEB J ; 34(9): 11997-12008, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32738093

RESUMO

Hematopoietic stem and progenitor cells (HSPCs) have the ability to self-renew and differentiate into various blood cells, thus playing an important role in maintenance of lifelong hematopoiesis. Brahma-related gene 1 (BRG1), which acts as the ATP subunit of mammalian SWI-SNF-related chromatin remodeling complexes, is involved in human acute myeloid leukemia and highly expresses in short-term HSPCs. But its role and regulatory mechanism for HSPC development have not yet been well established. Here, we generated a brg1 knockout zebrafish model using TALEN technology. We found that in brg1-/- embryo, the primitive hematopoiesis remained well, while definitive hematopoiesis formation was significantly impaired. The number of hemogenic endothelial cells was decreased, further affecting definitive hematopoiesis with reduced myeloid and lymphoid cells. During embryogenesis, the nitric oxide (NO) microenvironment in brg1-/- embryo was seriously damaged and the reduction of HSPCs could be partially rescued by a NO donor. Chromatin immunoprecipitation (ChIP) assays showed that BRG1 could bind to the promoter of KLF2 and trigger its transcriptional activity of NO synthase. Our findings show that Brg1 promotes klf2a expression in hemogenic endothelium and highlight a novel mechanism for HSPC formation and maintenance.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Embrião não Mamífero/embriologia , Hematopoese , Células-Tronco Hematopoéticas/metabolismo , Nicho de Células-Tronco , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Inativação de Genes , Células-Tronco Hematopoéticas/citologia , Fatores de Transcrição Kruppel-Like/biossíntese , Fatores de Transcrição Kruppel-Like/genética , Óxido Nítrico/genética , Óxido Nítrico/metabolismo , Elementos de Resposta , Transcrição Gênica , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/biossíntese , Proteínas de Peixe-Zebra/genética
7.
J Biol Chem ; 294(38): 13953-13963, 2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31362982

RESUMO

Mutations in human prominin 1 (PROM1), encoding a transmembrane glycoprotein localized mainly to plasma membrane protrusions, have been reported to cause retinitis pigmentosa, macular degeneration, and cone-rod dystrophy. Although the structural role of PROM1 in outer-segment (OS) morphogenesis has been demonstrated in Prom1-knockout mouse, the mechanisms underlying these complex disease phenotypes remain unclear. Here, we utilized a zebrafish model to further investigate PROM1's role in the retina. The Prom1 orthologs in zebrafish include prom1a and prom1b, and our results showed that prom1b, rather than prom1a, plays an important role in zebrafish photoreceptors. Loss of prom1b disrupted OS morphogenesis, with rods and cones exhibiting differences in impairment: cones degenerated at an early age, whereas rods remained viable but with an abnormal OS, even at 9 months postfertilization. Immunofluorescence experiments with WT zebrafish revealed that Prph2, an ortholog of the human transmembrane protein peripherin 2 and also associated with OS formation, is localized to the edge of OS and is more highly expressed in the cone OS than in the rod OS. Moreover, we found that Prom1b deletion causes mislocalization of Prph2 and disrupts its oligomerization. We conclude that the variation in Prph2 levels between cones and rods was one of the reasons for the different PROM1 mutation-induced phenotypes of these retinal structures. These findings expand our understanding of the phenotypes caused by PROM1 mutations and provide critical insights into its function.


Assuntos
Antígeno AC133/metabolismo , Células Fotorreceptoras/metabolismo , Segmento Externo da Célula Bastonete/metabolismo , Antígeno AC133/genética , Animais , Distrofias de Cones e Bastonetes/genética , Modelos Animais de Doenças , Células HeLa , Humanos , Degeneração Macular/metabolismo , Proteínas de Membrana/metabolismo , Morfogênese , Mutação , Periferinas/genética , Retina/metabolismo , Retina/fisiologia , Células Fotorreceptoras Retinianas Cones/metabolismo , Degeneração Retiniana/genética , Degeneração Retiniana/fisiopatologia , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Retinose Pigmentar/genética , Deleção de Sequência , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
8.
Biochim Biophys Acta Mol Basis Dis ; 1865(10): 2694-2705, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31348989

RESUMO

Leber congenital amaurosis (LCA) is the most serious form of inherited retinal dystrophy that leads to blindness or severe visual impairment within a few months after birth. Approximately 1-2% of the reported cases are caused by mutations in the LCA5 gene. This gene encodes a ciliary protein called LCA5 that is localized to the connecting cilium of photoreceptors. The retinal phenotypes caused by LCA5 mutations and the underlying pathological mechanisms are still not well understood. In this study, we knocked out the lca5 gene in zebrafish using CRISPR/Cas9 technology. An early onset visual defect is detected by the ERG in 7 dpf lca5-/- zebrafish. Histological analysis by HE staining and immunofluorescence reveal progressive degeneration of rod and cone photoreceptors, with a pattern that cones are more severely affected than rods. In addition, ultrastructural analysis by transmission electron microscopy shows disordered and broken membrane discs in rods' and cones' outer segments, respectively. In our lca5-/- zebrafish, the red-cone opsin and cone α-transducin are selectively mislocalized to the inner segment and synaptic terminal. Moreover, we found that Ift88, a key component of the intraflagellar transport complex, is retained in the outer segments. These data suggest that the intraflagellar transport complex-mediated outer segment protein trafficking might be impaired due to lca5 deletion, which finally leads to a type of retinal degeneration mimicking the phenotype of cone-rod dystrophy in human. Our work provides a novel animal model to study the physiological function of LCA5 and develop potential treatments of LCA.


Assuntos
Distrofias de Cones e Bastonetes/genética , Predisposição Genética para Doença/genética , Amaurose Congênita de Leber/genética , Amaurose Congênita de Leber/metabolismo , Transporte Proteico/fisiologia , Peixe-Zebra/genética , Animais , Sistemas CRISPR-Cas , Cílios/metabolismo , Modelos Animais de Doenças , Proteínas do Olho/metabolismo , Técnicas de Inativação de Genes , Humanos , Amaurose Congênita de Leber/patologia , Proteínas Associadas aos Microtúbulos , Fenótipo , Retina/metabolismo , Células Fotorreceptoras Retinianas Cones/patologia , Degeneração Retiniana/genética , Degeneração Retiniana/patologia , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
9.
Biochim Biophys Acta Mol Basis Dis ; 1865(6): 1273-1283, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30684641

RESUMO

Mutations in the photoreceptor cell-specific nuclear receptor gene Nr2e3 increased the number of S-cone photoreceptors in human and murine retinas and led to retinal degeneration that involved photoreceptor and non-photoreceptor cells. The mechanisms underlying these complex phenotypes remain unclear. In the hope of understanding the precise role of Nr2e3 in photoreceptor cell fate determination and differentiation, we generated a line of Nr2e3 knockout zebrafish using CRISPR technology. In these Nr2e3-null animals, rod precursors undergo terminal mitoses but fail to differentiate as rods. Rod-specific genes are not expressed and the outer segment (OS) fails to form. Formation and differentiation of cone photoreceptors is normal. Specifically, there is no increase in the number of UV-cone or S-cone photoreceptors. Laminated retinal structure is maintained. After normal development, L-/M-cones selectively degenerate, with progressive shortening of OS that starts at age 1 month. The amount of cone phototransduction proteins is concomitantly reduced, whereas UV- and S-cones have normal OS lengths even at age 10 months. In vitro studies show Nr2e3 synergizes with Crx and Nrl to enhance rhodopsin gene expression. Nr2e3 does not affect cone opsin expression. Our results extend the knowledge of Nr2e3's roles and have specific implications for the interpretation of the phenotypes observed in human and murine retinas. Furthermore, our model may offer new opportunities in finding treatments for enhanced S-cone syndrome (ESCS) and other retinal degenerative diseases.


Assuntos
Diferenciação Celular/genética , Mutação , Receptores Citoplasmáticos e Nucleares/genética , Células Fotorreceptoras Retinianas Cones/patologia , Degeneração Retiniana/genética , Células Fotorreceptoras Retinianas Bastonetes/metabolismo , Proteínas de Peixe-Zebra/genética , Animais , Sequência de Bases , Sistemas CRISPR-Cas , Técnicas de Inativação de Genes , Células HEK293 , Humanos , Microscopia Eletrônica de Transmissão , Receptores Citoplasmáticos e Nucleares/metabolismo , Retina/embriologia , Retina/crescimento & desenvolvimento , Retina/ultraestrutura , Células Fotorreceptoras Retinianas Cones/metabolismo , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia , Células Fotorreceptoras Retinianas Bastonetes/citologia , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
10.
Blood ; 133(8): 805-815, 2019 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-30482793

RESUMO

Hematopoietic stem and progenitor cells (HSPCs) originate from the hemogenic endothelium via the endothelial-to-hematopoietic transition, are self-renewing, and replenish all lineages of blood cells throughout life. BCAS2 (breast carcinoma amplified sequence 2) is a component of the spliceosome and is involved in multiple biological processes. However, its role in hematopoiesis remains unknown. We established a bcas2 knockout zebrafish model by using transcription activator-like effector nucleases. The bcas2 -/- zebrafish showed severe impairment of HSPCs and their derivatives during definitive hematopoiesis. We also observed significant signs of HSPC apoptosis in the caudal hematopoietic tissue of bcas2 -/- zebrafish, which may be rescued by suppression of p53. Furthermore, we show that the bcas2 deletion induces an abnormal alternative splicing of Mdm4 that predisposes cells to undergo p53-mediated apoptosis, which provides a mechanistic explanation of the deficiency observed in HSPCs. Our findings revealed a novel and vital role for BCAS2 during HSPC maintenance in zebrafish.


Assuntos
Embrião não Mamífero/embriologia , Desenvolvimento Embrionário , Células-Tronco Hematopoéticas/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Animais , Animais Geneticamente Modificados/embriologia , Animais Geneticamente Modificados/genética , Técnicas de Silenciamento de Genes , Proteínas de Neoplasias/genética , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
11.
Autophagy ; 15(3): 453-465, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30205735

RESUMO

Macroautophagy/autophagy is an important intracellular mechanism for the maintenance of cellular homeostasis. Here we show that the CERKL (ceramide kinase like) gene, a retinal degeneration (RD) pathogenic gene, plays a critical role in regulating autophagy by stabilizing SIRT1. In vitro and in vivo, suppressing CERKL results in impaired autophagy. SIRT1 is one of the main regulators of acetylation/deacetylation in autophagy. In CERKL-depleted retinas and cells, SIRT1 is downregulated. ATG5 and ATG7, 2 essential components of autophagy, show a higher degree of acetylation in CERKL-depleted cells. Overexpression of SIRT1 rescues autophagy in CERKL-depleted cells, whereas CERKL loses its function of regulating autophagy in SIRT1-depleted cells, and overexpression of CERKL upregulates SIRT1. Finally, we show that CERKL directly interacts with SIRT1, and may regulate its phosphorylation at Ser27 to stabilize SIRT1. These results show that CERKL is an important regulator of autophagy and it plays this role by stabilizing the deacetylase SIRT1.


Assuntos
Autofagia/genética , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Degeneração Retiniana/genética , Sirtuína 1/metabolismo , Proteínas de Peixe-Zebra/genética , Acetilação , Animais , Autofagossomos/metabolismo , Proteína 5 Relacionada à Autofagia/química , Proteína 5 Relacionada à Autofagia/genética , Proteína 5 Relacionada à Autofagia/metabolismo , Proteína 7 Relacionada à Autofagia/química , Proteína 7 Relacionada à Autofagia/genética , Proteína 7 Relacionada à Autofagia/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Humanos , Fosforilação , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Processamento de Proteína Pós-Traducional/genética , Retina/patologia , Epitélio Pigmentado da Retina/metabolismo , Retinose Pigmentar/genética , Sirtuína 1/química , Sirtuína 1/genética , Regulação para Cima , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
12.
Hum Genet ; 137(10): 779-794, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30242501

RESUMO

Most cases of Usher syndrome type II (USH2) are due to mutations in the USH2A gene. There are no effective treatments or ideal animal models for this disease, and the pathological mechanisms of USH2 caused by USH2A mutations are still unknown. Here, we constructed a ush2a knockout (ush2a-/-) zebrafish model using TALEN technology to investigate the molecular pathology of USH2. An early onset auditory disorder and abnormal morphology of inner ear stereocilia were identified in the ush2a-/- zebrafish. Consequently, the disruption of Ush2a in zebrafish led to a hearing impairment, like that in mammals. Electroretinography (ERG) test indicated that deletion of Ush2a affected visual function at an early stage, and histological analysis revealed that the photoreceptors progressively degenerated. Rod degeneration occurred prior to cone degeneration in ush2a-/- zebrafish, which is consistent with the classical description of the progression of retinitis pigmentosa (RP). Destruction of the outer segments (OSs) of rods led to the down-regulation of phototransduction cascade proteins at late stage. The expression of Ush1b and Ush1c was up-regulated when Ush2a was null. We also found that disruption of fibronectin assembly at the retinal basement membrane weakened cell adhesion in ush2a-/- mutants. In summary, for the first time, we generated a ush2a knockout zebrafish line with auditory disorder and retinal degeneration which mimicked the symptoms of patients, and revealed that disruption of fibronectin assembly may be one of the factors underlying RP. This model may help us to better understand the pathogenic mechanism and find treatment for USH2 in the future.


Assuntos
Proteínas da Matriz Extracelular , Técnicas de Inativação de Genes , Síndromes de Usher , Proteínas de Peixe-Zebra , Peixe-Zebra , Animais , Modelos Animais de Doenças , Eletrorretinografia , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Humanos , Síndromes de Usher/genética , Síndromes de Usher/metabolismo , Síndromes de Usher/patologia , Síndromes de Usher/fisiopatologia , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
13.
Cell Death Dis ; 8(10): e3082, 2017 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-28981088

RESUMO

Cataract refers to opacities of the lens that impede the passage of light. Mutations in heat shock transcription factor 4 (HSF4) have been associated with cataract; however, the mechanisms regarding how mutations in HSF4 cause cataract are still obscure. In this study, we generated an hsf4 knockout zebrafish model using TALEN technology. The mutant zebrafish developed an early-onset cataract with multiple developmental defects in lens. The epithelial cells of the lens were overproliferated, resulting in the overabundance of lens fiber cells in hsf4null zebrafish lens. Consequently, the arrangement of the lens fiber cells became more disordered and irregular with age. More importantly, the terminal differentiation of the lens fiber cell was interrupted as the organelles cannot be cleaved in due time. In the cultured human lens epithelial cells, HSF4 could stabilize and retain p53 in the nucleus to activate its target genes such as fas cell surface death receptor (Fas) and Bcl-2-associated X apoptosis regulator (Bax). In the hsf4null fish, both p53 and activated-caspase3 were significantly decreased. Combined with the finding that the denucleation defect could be partially rescued through microinjection of p53, fas and bax mRNA into the mutant embryos, we directly proved that HSF4 promotes lens fiber cell differentiation by activating p53 and its downstream regulators. The data we presented suggest that apoptosis-related genes are involved in the lens fiber cell differentiation. Our finding that HSF4 functions in the upstream to activate these genes highlighted the new regulatory modes of HSF4 in the terminal differentiation of lens fiber cell.


Assuntos
Catarata/genética , Diferenciação Celular/genética , Fatores de Transcrição de Choque Térmico/genética , Proteína Supressora de Tumor p53/genética , Animais , Caspase 3/genética , Catarata/patologia , Linhagem Celular , Núcleo Celular/genética , Núcleo Celular/patologia , Proteínas de Ligação a DNA/genética , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Cristalino/crescimento & desenvolvimento , Cristalino/metabolismo , Cristalino/patologia , Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento , Proteína X Associada a bcl-2/genética , Receptor fas/genética
14.
Sci Rep ; 7: 46098, 2017 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-28378834

RESUMO

Mutations in EYS are associated with autosomal recessive retinitis pigmentosa (arRP) and autosomal recessive cone-rod dystrophy (arCRD) however, the function of EYS and the molecular mechanisms of how these mutations cause retinal degeneration are still unclear. Because EYS is absent in mouse and rat, and the structure of the retina differs substantially between humans and Drosophila, we utilised zebrafish as a model organism to study the function of EYS in the retina. We constructed an EYS-knockout zebrafish-line by TALEN technology which showed visual impairment at an early age, while the histological and immunofluorescence assays indicated the presence of progressive retinal degeneration with a cone predominately affected pattern. These phenotypes recapitulate the clinical manifestations of arCRD patients. Furthermore, the EYS-/- zebrafish also showed mislocalisation of certain outer segment proteins (rhodopsin, opn1lw, opn1sw1, GNB3 and PRPH2), and disruption of actin filaments in photoreceptors. Protein mislocalisation may, therefore, disrupt the function of cones and rods in these zebrafish and cause photoreceptor death. Collectively, these results point to a novel role for EYS in maintaining the morphological structure of F-actin and in protein transport, loss of this function might be the trigger for the resultant cellular events that ultimately lead to photoreceptor death.


Assuntos
Actinas/metabolismo , Distrofias de Cones e Bastonetes/metabolismo , Proteínas do Olho/metabolismo , Deleção de Genes , Segmento Externo da Célula Bastonete/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Envelhecimento/patologia , Animais , Apoptose , Sequência de Bases , Distrofias de Cones e Bastonetes/patologia , Distrofias de Cones e Bastonetes/fisiopatologia , Eletrorretinografia , Técnicas de Inativação de Genes , Transdução de Sinal Luminoso , Segmento Externo da Célula Bastonete/patologia , Segmento Externo da Célula Bastonete/ultraestrutura , Nucleases dos Efetores Semelhantes a Ativadores de Transcrição/metabolismo , Visão Ocular
15.
Hum Mol Genet ; 26(12): 2335-2345, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28398482

RESUMO

In humans, CERKL mutations cause widespread retinal degeneration: early dysfunction and loss of rod and cone photoreceptors in the outer retina and, progressively, death of cells in the inner retina. Despite intensive efforts, the function of CERKL remains obscure and studies in animal models have failed to clarify the disease mechanism of CERKL mutations. To address this gap in knowledge, we have generated a stable CERKL knockout zebrafish model by TALEN technology and a 7bp deletion in CERKL cDNA that caused the premature termination of CERKL. These CERKL-/- animals showed progressive degeneration of photoreceptor outer segments (OSs) and increased apoptosis of retinal cells, including those in the outer and inner retinal layers. Additionally, we confirmed by immunofluorescence and western-blot that rod degeneration in CERKL-/- zebrafish occurred earlier and was more significant than that in cone cells. Accumulation of shed OSs in the interphotoreceptor matrix was observed by transmission election microscopy (TEM). This suggested that CERKL may regulate the phagocytosis of OSs by the retinal pigment epithelium (RPE). We further found that the phagocytosis-associated protein MERTK was significantly reduced in CERKL-/- zebrafish. Additionally, in ARPE-19 cell lines, knockdown of CERKL also decreased the mRNA and protein level of MERTK, as well as the ox-POS phagocytosis. We conclude that CERKL deficiency in zebrafish may cause rod-cone dystrophy, but not cone-rod dystrophy, while interfering with the phagocytosis function of RPE associated with down-regulation of the expression of MERTK.


Assuntos
Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Animais , Linhagem Celular , Regulação para Baixo , Técnicas de Inativação de Genes/métodos , Humanos , Mutação , Fagocitose/genética , Células Fotorreceptoras , RNA Mensageiro/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Retina/metabolismo , Células Fotorreceptoras Retinianas Cones/metabolismo , Degeneração Retiniana/genética , Epitélio Pigmentado da Retina/metabolismo , Retinose Pigmentar/metabolismo , Peixe-Zebra/genética
16.
J Biol Chem ; 292(15): 6225-6239, 2017 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-28209709

RESUMO

Mutations in retinitis pigmentosa 2 (RP2) account for 10-20% of X-linked retinitis pigmentosa (RP) cases. The encoded RP2 protein is implicated in ciliary trafficking of myristoylated and prenylated proteins in photoreceptor cells. To date >70 mutations in RP2 have been identified. How these mutations disrupt the function of RP2 is not fully understood. Here we report a novel in-frame 12-bp deletion (c.357_368del, p.Pro120_Gly123del) in zebrafish rp2 The mutant zebrafish shows reduced rod phototransduction proteins and progressive retinal degeneration. Interestingly, the protein level of mutant Rp2 is almost undetectable, whereas its mRNA level is near normal, indicating a possible post-translational effect of the mutation. Consistent with this hypothesis, the equivalent 12-bp deletion in human RP2 markedly impairs RP2 protein stability and reduces its protein level. Furthermore, we found that a majority of the RP2 pathogenic mutations (including missense, single-residue deletion, and C-terminal truncation mutations) severely destabilize the RP2 protein. The destabilized RP2 mutant proteins are degraded via the proteasome pathway, resulting in dramatically decreased protein levels. The remaining non-destabilizing mutations T87I, R118H/R118G/R118L/R118C, E138G, and R211H/R211L are suggested to impair the interaction between RP2 and its protein partners (such as ARL3) or with as yet unknown partners. By utilizing a combination of in silico, in vitro, and in vivo approaches, our work comprehensively indicates that loss of RP2 protein structural stability is the predominating pathogenic consequence for most RP2 mutations. Our study also reveals a role of the C-terminal domain of RP2 in maintaining the overall protein stability.


Assuntos
Sequência de Bases , Proteínas do Olho/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Membrana/metabolismo , Degeneração Retiniana , Deleção de Sequência , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Proteínas do Olho/genética , Proteínas de Ligação ao GTP , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas de Membrana/genética , Domínios Proteicos , Estabilidade Proteica , Degeneração Retiniana/genética , Degeneração Retiniana/metabolismo , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
17.
Sci Rep ; 6: 32173, 2016 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-27572304

RESUMO

We sequenced RNA transcripts from the testicles of healthy male mice, divided into a control group with distilled water and two experimental groups with 50 and 100 mg/l NaF in drinking water for 56 days. Bowtie/Tophat were used to align 50-bp paired-end reads into transcripts, Cufflinks to measure the relative abundance of each transcript and IPA to analyze RNA-Sequencing data. In the 100 mg/l NaF-treated group, four pathways related to IL-17, TGF-ß and other cellular growth factor pathways were overexpressed. The mRNA expression of IL-17RA, IL-17RC, MAP2K1, MAP2K2, MAP2K3 and MAPKAPK2, monitored by qRT-PCR, increased remarkably in the 100 mg/L NaF group and coincided with the result of RNA-Sequencing. Fluoride exposure could disrupt spermatogenesis and testicles in male mice by influencing many signaling pathways and genes, which work on the immune signal transduction and cellular metabolism. The high expression of the IL-17 signal pathway was a response to the invasion of the testicular immune system due to extracellular fluoride. The PI3-kinase/AKT, MAPKs and the cytokines in TGF-ß family were contributed to control the IL-17 pathway activation and maintain the immune privilege and spermatogenesis. All the findings provided new ideas for further molecular researches of fluorosis on the reproduction and immune response mechanism.


Assuntos
Fluoretos/toxicidade , Interleucina-17/imunologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Testículo/imunologia , Animais , Sequenciamento de Nucleotídeos em Larga Escala , Sistema de Sinalização das MAP Quinases/imunologia , Masculino , Camundongos , Espermatogênese/imunologia , Testículo/patologia
18.
Sci Rep ; 6: 24226, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-27052676

RESUMO

Disseminated superficial porokeratosis (DSP) is a rare keratinization disorder of the epidermis. It is characterized by keratotic lesions with an atrophic center encircled by a prominent peripheral ridge. We investigated the genetic basis of DSP in two five-generation Chinese families with members diagnosed with DSP. By whole-exome sequencing, we sequencing identified a nonsense variation c.412C > T (p.Arg138*) in the phosphomevalonate kinase gene (PMVK), which encodes a cytoplasmic enzyme catalyzing the conversion of mevalonate 5-phosphate to mevalonate 5-diphosphate in the mevalonate pathway. By co-segregation and haplotype analyses as well as exclusion testing of 500 normal control subjects, we demonstrated that this genetic variant was involved in the development of DSP in both families. We obtained further evidence from studies using HaCaT cells as models that this variant disturbed subcellular localization, expression and solubility of PMVK. We also observed apparent apoptosis in and under the cornoid lamella of PMVK-deficient lesional tissues, with incomplete differentiation of keratinocytes. Our findings suggest that PMVK is a potential novel gene involved in the pathogenesis of DSP and PMVK deficiency or abnormal keratinocyte apoptosis could lead to porokeratosis.


Assuntos
Genes Dominantes , Predisposição Genética para Doença/genética , Mutação , Fosfotransferases (Aceptor do Grupo Fosfato)/genética , Poroceratose/genética , Adolescente , Adulto , Povo Asiático/genética , Sequência de Bases , Linhagem Celular , Criança , Pré-Escolar , China , Análise Mutacional de DNA , Saúde da Família , Feminino , Predisposição Genética para Doença/etnologia , Humanos , Masculino , Microscopia Confocal , Linhagem , Fosfotransferases (Aceptor do Grupo Fosfato)/metabolismo , Poroceratose/enzimologia , Poroceratose/etnologia , Adulto Jovem
19.
Arch Toxicol ; 88(2): 533-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23881332

RESUMO

Reproductive process covers lots of procedures, including capacitation, hyperactivation, chemotaxis and the acrosome reaction. Each plays an important role in the success of fertilization. Although multiple studies have reported the toxic effects of fluoride on the male reproduction, the effect of fluoride on sperm chemotaxis is little known. This study is to examine the effect of fluoride on the sperm chemotaxis and then to reveal the underling mechanisms of fluoride toxicity in sperm chemotaxis. 260 healthy Kunming male mice (8 weeks old) were randomly divided into four groups and exposed to 50, 100, 150 mg NaF/L in the drinking water for 8 weeks. At the end of the exposure, sperm chemotaxis was examined using a microchannel-based device. Ca(2+) concentration, adenylate cyclase (AC) content and mRNA expression of mACIII, mACVIII, Golf alpha, CatSper1, CatSper2 were measured to elucidate the possible molecular mechanisms. The results showed that the percentage of chemotactic sperm was decreased by NaF in a dose-dependent manner. In the 100 and 150 mg/L groups, Ca(2+) concentration and AC content were notably lower than the control group. Compared with the control group, mRNA expression of CatSper1 in the 100 and 150 mg/L treatment groups was decreased significantly, and other genes showed no statistical difference. These data suggested that excessive fluoride did adversely affect sperm chemotaxis. The alteration of Ca(2+) concentration, AC content and CatSper1 mRNA expression level may play a key role in the mechanism underlying the affection.


Assuntos
Quimiotaxia/efeitos dos fármacos , Fluoreto de Sódio/toxicidade , Espermatozoides/efeitos dos fármacos , Adenilil Ciclases/genética , Adenilil Ciclases/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Cálcio/metabolismo , Canais de Cálcio/genética , Feminino , Subunidades alfa de Proteínas de Ligação ao GTP/genética , Expressão Gênica/efeitos dos fármacos , Masculino , Camundongos , Proteínas de Plasma Seminal/genética , Espermatozoides/metabolismo
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