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1.
EMBO J ; 42(15): e112900, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37350545

RESUMEN

The scaffolding protein angiomotin (AMOT) is indispensable for vertebrate embryonic angiogenesis. Here, we report that AMOT undergoes cleavage in the presence of lysophosphatidic acid (LPA), a lipid growth factor also involved in angiogenesis. AMOT cleavage is mediated by aspartic protease DNA damage-inducible 1 homolog 2 (DDI2), and the process is tightly regulated by a signaling axis including neurofibromin 2 (NF2), tankyrase 1/2 (TNKS1/2), and RING finger protein 146 (RNF146), which induce AMOT membrane localization, poly ADP ribosylation, and ubiquitination, respectively. In both zebrafish and mice, the genetic inactivation of AMOT cleavage regulators leads to defective angiogenesis, and the phenotype is rescued by the overexpression of AMOT-CT, a C-terminal AMOT cleavage product. In either physiological or pathological angiogenesis, AMOT-CT is required for vascular expansion, whereas uncleavable AMOT represses this process. Thus, our work uncovers a signaling pathway that regulates angiogenesis by modulating a cleavage-dependent activation of AMOT.


Asunto(s)
Angiomotinas , Pez Cebra , Animales , Ratones , Pez Cebra/metabolismo , Proteínas de Microfilamentos/metabolismo , Péptido Hidrolasas , Péptidos y Proteínas de Señalización Intercelular/genética
2.
Cell ; 138(3): 525-36, 2009 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-19665974

RESUMEN

Modulation of intracellular chloride concentration ([Cl(-)](i)) plays a fundamental role in cell volume regulation and neuronal response to GABA. Cl(-) exit via K-Cl cotransporters (KCCs) is a major determinant of [Cl(-)](I); however, mechanisms governing KCC activities are poorly understood. We identified two sites in KCC3 that are rapidly dephosphorylated in hypotonic conditions in cultured cells and human red blood cells in parallel with increased transport activity. Alanine substitutions at these sites result in constitutively active cotransport. These sites are highly phosphorylated in plasma membrane KCC3 in isotonic conditions, suggesting that dephosphorylation increases KCC3's intrinsic transport activity. Reduction of WNK1 expression via RNA interference reduces phosphorylation at these sites. Homologous sites are phosphorylated in all human KCCs. KCC2 is partially phosphorylated in neonatal mouse brain and dephosphorylated in parallel with KCC2 activation. These findings provide insight into regulation of [Cl(-)](i) and have implications for control of cell volume and neuronal function.


Asunto(s)
Simportadores/química , Simportadores/metabolismo , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Humanos , Ratones , Datos de Secuencia Molecular , Fosforilación , Alineación de Secuencia , Cotransportadores de K Cl
3.
Nature ; 564(7734): 119-124, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30455424

RESUMEN

Haematopoietic stem and progenitor cells (HSPCs) give rise to all blood lineages that support the entire lifespan of vertebrates1. After HSPCs emerge from endothelial cells within the developing dorsal aorta, homing allows the nascent cells to anchor in their niches for further expansion and differentiation2-5. Unique niche microenvironments, composed of various blood vessels as units of microcirculation and other niche components such as stromal cells, regulate this process6-9. However, the detailed architecture of the microenvironment and the mechanism for the regulation of HSPC homing remain unclear. Here, using advanced live imaging and a cell-labelling system, we perform high-resolution analyses of the HSPC homing in caudal haematopoietic tissue of zebrafish (equivalent to the fetal liver in mammals), and reveal the role of the vascular architecture in the regulation of HSPC retention. We identify a VCAM-1+ macrophage-like niche cell population that patrols the inner surface of the venous plexus, interacts with HSPCs in an ITGA4-dependent manner, and directs HSPC retention. These cells, named 'usher cells', together with caudal venous capillaries and plexus, define retention hotspots within the homing microenvironment. Thus, the study provides insights into the mechanism of HSPC homing and reveals the essential role of a VCAM-1+ macrophage population with patrolling behaviour in HSPC retention.


Asunto(s)
Células Endoteliales/citología , Células Madre Hematopoyéticas/citología , Macrófagos/metabolismo , Nicho de Células Madre , Molécula 1 de Adhesión Celular Vascular/metabolismo , Animales , Diferenciación Celular , Movimiento Celular , Microambiente Celular , Integrinas/genética , Integrinas/metabolismo , Pez Cebra , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo
4.
Sensors (Basel) ; 24(14)2024 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-39066111

RESUMEN

In air traffic control (ATC), speech communication with radio transmission is the primary way to exchange information between the controller and the pilot. As a result, the integration of automatic speech recognition (ASR) systems holds immense potential for reducing controllers' workload and plays a crucial role in various ATC scenarios, which is particularly significant for ATC research. This article provides a comprehensive review of ASR technology's applications in the ATC communication system. Firstly, it offers a comprehensive overview of current research, including ATC corpora, ASR models, evaluation measures and application scenarios. A more comprehensive and accurate evaluation methodology tailored for ATC is proposed, considering advancements in communication sensing systems and deep learning techniques. This methodology helps researchers in enhancing ASR systems and improving the overall performance of ATC systems. Finally, future research recommendations are identified based on the primary challenges and issues. The authors sincerely hope this work will serve as a clear technical roadmap for ASR endeavors within the ATC domain and make a valuable contribution to the research community.

5.
Sensors (Basel) ; 24(9)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38732816

RESUMEN

Target detection technology based on unmanned aerial vehicle (UAV)-derived aerial imagery has been widely applied in the field of forest fire patrol and rescue. However, due to the specificity of UAV platforms, there are still significant issues to be resolved such as severe omission, low detection accuracy, and poor early warning effectiveness. In light of these issues, this paper proposes an improved YOLOX network for the rapid detection of forest fires in images captured by UAVs. Firstly, to enhance the network's feature-extraction capability in complex fire environments, a multi-level-feature-extraction structure, CSP-ML, is designed to improve the algorithm's detection accuracy for small-target fire areas. Additionally, a CBAM attention mechanism is embedded in the neck network to reduce interference caused by background noise and irrelevant information. Secondly, an adaptive-feature-extraction module is introduced in the YOLOX network's feature fusion part to prevent the loss of important feature information during the fusion process, thus enhancing the network's feature-learning capability. Lastly, the CIoU loss function is used to replace the original loss function, to address issues such as excessive optimization of negative samples and poor gradient-descent direction, thereby strengthening the network's effective recognition of positive samples. Experimental results show that the improved YOLOX network has better detection performance, with mAP@50 and mAP@50_95 increasing by 6.4% and 2.17%, respectively, compared to the traditional YOLOX network. In multi-target flame and small-target flame scenarios, the improved YOLO model achieved a mAP of 96.3%, outperforming deep learning algorithms such as FasterRCNN, SSD, and YOLOv5 by 33.5%, 7.7%, and 7%, respectively. It has a lower omission rate and higher detection accuracy, and it is capable of handling small-target detection tasks in complex fire environments. This can provide support for UAV patrol and rescue applications from a high-altitude perspective.

6.
Arterioscler Thromb Vasc Biol ; 42(6): 772-788, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35477278

RESUMEN

BACKGROUND: Arteriogenesis plays a critical role in maintaining adequate tissue blood supply and is related to a favorable prognosis in arterial occlusive diseases. Strategies aimed at promoting arteriogenesis have thus far not been successful because the factors involved in arteriogenesis remain incompletely understood. Previous studies suggest that evolutionarily conserved KANK4 (KN motif and ankyrin repeat domain-containing proteins 4) might involve in vertebrate vessel development. However, how the KANK4 regulates vessel function remains unknown. We aim to determine the role of endothelial cell-specifically expressed KANK4 in arteriogenesis. METHODS: The role of KANK4 in regulating arteriogenesis was evaluated using Kank4-/- and KANK4iECOE mice. Molecular mechanisms underlying KANK4-potentiated arteriogenesis were investigated by employing RNA transcriptomic profiling and mass spectrometry analysis. RESULTS: By analyzing Kank4-EGFP reporter mice, we showed that KANK4 was specifically expressed in endothelial cells. In particular, KANK4 displayed a dynamic expression pattern from being ubiquitously expressed in all endothelial cells of the developing vasculature to being explicitly expressed in the endothelial cells of arterioles and arteries in matured vessels. In vitro microfluidic chip-based vascular morphology analysis and in vivo hindlimb ischemia assays using Kank4-/- and KANK4iECOE mice demonstrated that deletion of KANK4 impaired collateral artery growth and the recovery of blood perfusion, whereas KANK4 overexpression leads to increased vessel caliber and blood perfusion. Bulk RNA sequencing and Co-immunoprecipitation/mass spectrometry (Co-IP/MS) analysis identified that KANK4 promoted EC proliferation and collateral artery remodeling through coupling VEGFR2 (vascular endothelial growth factor receptor 2) to TALIN-1, which augmented the activation of the VEGFR2 signaling cascade. CONCLUSIONS: This study reveals a novel role for KANK4 in arteriogenesis in response to ischemia. KANK4 links VEGFR2 to TALIN-1, resulting in enhanced VEGFR2 activation and increased EC proliferation, highlighting that KANK4 is a potential therapeutic target for promoting arteriogenesis for arterial occlusive diseases.


Asunto(s)
Arteriopatías Oclusivas , Neovascularización Fisiológica , Animales , Arteriopatías Oclusivas/metabolismo , Circulación Colateral , Modelos Animales de Enfermedad , Células Endoteliales/metabolismo , Miembro Posterior/irrigación sanguínea , Isquemia , Ratones , Ratones Noqueados , Músculo Esquelético/irrigación sanguínea , Flujo Sanguíneo Regional , Talina , Factor A de Crecimiento Endotelial Vascular/metabolismo
7.
Ecotoxicol Environ Saf ; 249: 114414, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36516626

RESUMEN

BACKGROUND: Based on self-report questionnaires, two previous epidemiological studies investigated the association between the exposure of women to antibiotics and their fertility. However, biomonitoring studies on low-dose antibiotic exposure, mainly from food and water, and its relation to the risk of infertility are missing. METHODS: Based on a case-control study design, 302 women with infertility (144 primary infertility, 158 secondary infertility) and 302 women with normal fertility, all aged 20-49 years, were recruited from Anhui Province, China, in 2020 and 2021. A total of 41 common antibiotics and two antibiotic metabolites in urine samples were determined by liquid chromatography-triple quadrupole tandem mass spectrometry (LC-QqQ-MS/MS). RESULTS: Twenty-eight antibiotics with detection rates from 10% to 100% in both cases (median concentration: ∼2.294 ng/mL) and controls (∼1.596 ng/mL) were included in the analysis. Logistic regression analysis revealed that after controlling for confounding factors, high concentrations of eight individual antibiotics (sulfamethoxazole, sulfaclozine, sulfamonomethoxine, penicillin G, chlorotetracycline, ofloxacin, norfloxacin, and cyadox) and four antibiotic classes (sulfonamides, tetracyclines, quinoxalines, and veterinary antibiotics) were related to a high risk of female infertility, with odds ratios (ORs) ranging from 1.30 to 2.86, except for chlorotetracycline (OR = 6.34), while another nine individual antibiotics (sulfamethazine, azithromycin, cefaclor, amoxicillin, oxytetracycline, pefloxacin, sarafloxacin, enrofloxacin, and florfenicol) and classes of chloramphenicol analogs and human antibiotics were related to a reduced risk of infertility, with ORs ranging from 0.70 to 0.20. Based on restricted cubic spline models after controlling for confounding factors, we observed that the relationship between all of the above protective antibiotics and infertility was nonlinear: A certain concentration could reduce the risk of female infertility while exceeding a safe dose could increase the risk of infertility. CONCLUSION: These results provide preliminary evidence that the effects of antibiotics on female fertility vary based on the active ingredient and usage and imply the importance of exposure dose. Future studies are needed to verify these results by controlling for multiple confounding factors.


Asunto(s)
Clortetraciclina , Infertilidad Femenina , Humanos , Femenino , Antibacterianos/análisis , Espectrometría de Masas en Tándem/métodos , Clortetraciclina/análisis , Infertilidad Femenina/inducido químicamente , Infertilidad Femenina/epidemiología , Estudios de Casos y Controles , China/epidemiología
8.
Genome Res ; 2019 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-31831591

RESUMEN

Genome editing by the well-established CRISPR/Cas9 technology has greatly facilitated our understanding of many biological processes. However, a complete whole-genome knockout for any species or model organism has rarely been achieved. Here, we performed a systematic knockout of all the genes (1333) on Chromosome 1 in zebrafish, successfully mutated 1029 genes, and generated 1039 germline-transmissible alleles corresponding to 636 genes. Meanwhile, by high-throughput bioinformatics analysis, we found that sequence features play pivotal roles in effective gRNA targeting at specific genes of interest, while the success rate of gene targeting positively correlates with GC content of the target sites. Moreover, we found that nearly one-fourth of all mutants are related to human diseases, and several representative CRISPR/Cas9-generated mutants are described here. Furthermore, we tried to identify the underlying mechanisms leading to distinct phenotypes between genetic mutants and antisense morpholino-mediated knockdown embryos. Altogether, this work has generated the first chromosome-wide collection of zebrafish genetic mutants by the CRISPR/Cas9 technology, which will serve as a valuable resource for the community, and our bioinformatics analysis also provides some useful guidance to design gene-specific gRNAs for successful gene editing.

9.
Biochem Biophys Res Commun ; 557: 8-13, 2021 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-33857842

RESUMEN

Precise quantification of vascular developments in Zebrafish requires continuous in-vivo 3D imaging. Here we employed a bi-directional light-sheet illumination microscope to characterize the development process of Zebrafish's intersegmental vessels. A Virtual Reality-based method was used to measure the lengths of intersegmental vessels (ISVs). The quantified growth rates of typical ISVs can be plotted, and unusual growth of some specific vessels was also observed.


Asunto(s)
Vasos Sanguíneos/embriología , Embrión no Mamífero/irrigación sanguínea , Microscopía/instrumentación , Pez Cebra/embriología , Animales , Animales Modificados Genéticamente , Vasos Sanguíneos/crecimiento & desarrollo , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Imagenología Tridimensional/métodos , Iluminación , Microscopía/métodos , Neovascularización Fisiológica , Pez Cebra/crecimiento & desarrollo
10.
Acta Pharmacol Sin ; 42(5): 801-813, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-32796956

RESUMEN

Grincamycins (GCNs) are a class of angucycline glycosides isolated from actinomycete Streptomyces strains that have potent antitumor activities, but their antitumor mechanisms remain unknown. In this study, we tried to identify the cellular target of grincamycin B (GCN B), one of most dominant and active secondary metabolites, using a combined strategy. We showed that GCN B-selective-induced apoptosis of human acute promyelocytic leukemia (APL) cell line NB4 through increase of ER stress and intracellular reactive oxygen species (ROS) accumulation. Using a strategy of combining phenotype, transcriptomics and protein microarray approaches, we identified that isocitrate dehydrogenase 1(IDH1) was the putative target of GCN B, and confirmed that GCNs were a subset of selective inhibitors targeting both wild-type and mutant IDH1 in vitro. It is well-known that IDH1 converts isocitrate to 2-oxoglutarate (2-OG), maintaining intracellular 2-OG homeostasis. IDH1 and its mutant as the target of GCN B were validated in NB4 cells and zebrafish model. Knockdown of IDH1 in NB4 cells caused the similar phenotype as GCN B treatment, and supplementation of N-acetylcysteine partially rescued the apoptosis caused by IDH1 interference in NB4 cells. In zebrafish model, GCN B effectively restored myeloid abnormality caused by overexpression of mutant IDH1(R132C). Taken together, we demonstrate that IDH1 is one of the antitumor targets of GCNs, suggesting wild-type IDH1 may be a potential target for hematological malignancies intervention in the future.


Asunto(s)
Antraquinonas/farmacología , Antineoplásicos/farmacología , Inhibidores Enzimáticos/farmacología , Glicósidos/farmacología , Isocitrato Deshidrogenasa/antagonistas & inhibidores , Animales , Antraquinonas/metabolismo , Antineoplásicos/metabolismo , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Estrés del Retículo Endoplásmico/efectos de los fármacos , Inhibidores Enzimáticos/metabolismo , Glicósidos/metabolismo , Humanos , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/metabolismo , Ácidos Cetoglutáricos/metabolismo , Simulación del Acoplamiento Molecular , Mutación , Unión Proteica , Especies Reactivas de Oxígeno/metabolismo , Pez Cebra
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