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1.
Sensors (Basel) ; 24(9)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38732800

RESUMEN

Transformer-based models have gained popularity in the field of natural language processing (NLP) and are extensively utilized in computer vision tasks and multi-modal models such as GPT4. This paper presents a novel method to enhance the explainability of transformer-based image classification models. Our method aims to improve trust in classification results and empower users to gain a deeper understanding of the model for downstream tasks by providing visualizations of class-specific maps. We introduce two modules: the "Relationship Weighted Out" and the "Cut" modules. The "Relationship Weighted Out" module focuses on extracting class-specific information from intermediate layers, enabling us to highlight relevant features. Additionally, the "Cut" module performs fine-grained feature decomposition, taking into account factors such as position, texture, and color. By integrating these modules, we generate dense class-specific visual explainability maps. We validate our method with extensive qualitative and quantitative experiments on the ImageNet dataset. Furthermore, we conduct a large number of experiments on the LRN dataset, which is specifically designed for automatic driving danger alerts, to evaluate the explainability of our method in scenarios with complex backgrounds. The results demonstrate a significant improvement over previous methods. Moreover, we conduct ablation experiments to validate the effectiveness of each module. Through these experiments, we are able to confirm the respective contributions of each module, thus solidifying the overall effectiveness of our proposed approach.

2.
Sensors (Basel) ; 23(21)2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37960360

RESUMEN

LiDAR point clouds are significantly impacted by snow in driving scenarios, introducing scattered noise points and phantom objects, thereby compromising the perception capabilities of autonomous driving systems. Current effective methods for removing snow from point clouds largely rely on outlier filters, which mechanically eliminate isolated points. This research proposes a novel translation model for LiDAR point clouds, the 'L-DIG' (LiDAR depth images GAN), built upon refined generative adversarial networks (GANs). This model not only has the capacity to reduce snow noise from point clouds, but it also can artificially synthesize snow points onto clear data. The model is trained using depth image representations of point clouds derived from unpaired datasets, complemented by customized loss functions for depth images to ensure scale and structure consistencies. To amplify the efficacy of snow capture, particularly in the region surrounding the ego vehicle, we have developed a pixel-attention discriminator that operates without downsampling convolutional layers. Concurrently, the other discriminator equipped with two-step downsampling convolutional layers has been engineered to effectively handle snow clusters. This dual-discriminator approach ensures robust and comprehensive performance in tackling diverse snow conditions. The proposed model displays a superior ability to capture snow and object features within LiDAR point clouds. A 3D clustering algorithm is employed to adaptively evaluate different levels of snow conditions, including scattered snowfall and snow swirls. Experimental findings demonstrate an evident de-snowing effect, and the ability to synthesize snow effects.

3.
J Cell Sci ; 133(23)2020 12 07.
Artículo en Inglés | MEDLINE | ID: mdl-33148610

RESUMEN

Activator of G-protein signaling 3 (AGS3, also known as GPSM1) regulates the trans-Golgi network. The AGS3 GoLoco motif binds to Gαi and thereby regulates the transport of proteins to the plasma membrane. Compaction of early embryos is based on the accumulation of E-cadherin (Cdh1) at cell-contacted membranes. However, how AGS3 regulates the transport of Cdh1 to the plasma membrane remains undetermined. To investigate this, AGS3 was knocked out using the Cas9-sgRNA system. Both trans-Golgi network protein 46 (TGN46, also known as TGOLN2) and transmembrane p24-trafficking protein 7 (TMED7) were tracked in early mouse embryos by tagging these proteins with a fluorescent protein label. We observed that the majority of the AGS3-edited embryos were developmentally arrested and were fragmented after the four-cell stage, exhibiting decreased accumulation of Cdh1 at the membrane. The trans-Golgi network and TMED7-positive vesicles were also dispersed and were not polarized near the membrane. Additionally, increased Gαi1 (encoded by GNAI1) expression could rescue AGS3-overexpressed embryos. In conclusion, AGS3 reinforces the dynamics of the trans-Golgi network and the transport of TMED7-positive cargo containing Cdh1 to the cell-contact surface during early mouse embryo development.


Asunto(s)
Inhibidores de Disociación de Guanina Nucleótido/genética , Transporte de Proteínas , Red trans-Golgi , Animales , Membrana Celular/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/metabolismo , Proteínas de Unión al GTP/metabolismo , Regulación del Desarrollo de la Expresión Génica , Ratones , Transducción de Señal , Red trans-Golgi/metabolismo
4.
FASEB J ; 33(7): 7882-7895, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30897005

RESUMEN

Phosphatase and tensin homolog-induced kinase 1 (PINK1) on the outer membranes of impaired mitochondria promotes mitophagy and regulates mitochondrial morphology. Mammalian oocytes and early embryos are mitochondria rich, but mitochondrial dynamics during preimplantation embryo development is not well-studied. To investigate whether PINK1 is required for mitochondrial dynamics in porcine preimplantation embryos, gene knockdown and inhibitors were used, and mitochondrial dynamics were observed by transmission electron microscopy. PINK1 knockdown significantly impaired blastocyst formation and quality, induced mitochondrial elongation and swelling, and reduced mitochondrial DNA copy number. PINK1 knockdown-induced mitochondrial elongation caused mitochondrial dysfunction, oxidative stress, and ATP deficiency, significantly increasing autophagy and apoptosis. Profission dynamin-related protein 1 overexpression prevented PINK1 knockdown-induced impairment of embryo development, mitochondrial elongation, and dysfunction. Thus, PINK1 promotes mitochondrial fission in porcine preimplantation embryos.-Niu, Y.-J., Nie, Z.-W., Shin, K.-T., Zhou, W., Cui, X.-S. PINK1 regulates mitochondrial morphology via promoting mitochondrial fission in porcine preimplantation embryos.


Asunto(s)
Blastocisto/fisiología , Mitocondrias/ultraestructura , Dinámicas Mitocondriales/fisiología , Proteínas Quinasas/fisiología , Adenosina Trifosfato/metabolismo , Animales , Apoptosis , Autofagia , Blastocisto/metabolismo , Dinaminas/genética , Dinaminas/fisiología , Desarrollo Embrionario , Dosificación de Gen , Técnicas de Silenciamiento del Gen , Genes Mitocondriales , Técnicas de Maduración In Vitro de los Oocitos , Potencial de la Membrana Mitocondrial , Microinyecciones , Partenogénesis , Proteínas Quinasas/genética , ARN Mensajero/administración & dosificación , ARN Mensajero/genética , Especies Reactivas de Oxígeno/metabolismo , Proteínas Recombinantes , Sus scrofa
5.
J Pineal Res ; 68(2): e12627, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31773776

RESUMEN

Melatonin, a major hormone of the pineal gland, exerts many beneficial effects on mitochondria. Several studies have shown that melatonin can protect against toxin-induced oocyte quality impairment during maturation. However, there is little information regarding the beneficial effects of melatonin on toxin-exposed early embryos, and the mechanisms underlying such effects have not been determined. Rotenone, a chemical widely used in agriculture, induces mitochondrial toxicity, therefore, damaging the reproductive system, impairing oocyte maturation, ovulation, and fertilization. We investigated whether melatonin attenuated rotenone exposure-induced impairment of embryo development by its mitochondrial protection effect. Activated oocytes were randomly assigned to four groups: the control, melatonin treatment, rotenone-exposed, and "rotenone + melatonin" groups. Treatment with melatonin abrogated rotenone-induced impairment of embryo development, mitochondrial dysfunction, and ATP deficiency, and significantly decreased oxidative stress and apoptosis. Melatonin also increased SIRT1 and PGC-1α expression, which promoted mitochondrial biogenesis. SIRT1 knockdown or pharmacological inhibition abolished melatonin's ability to revert rotenone-induced impairment. Thus, melatonin rescued rotenone-induced impairment of embryo development by reducing ROS production and promoting mitochondrial biogenesis. This study shows that melatonin rescues toxin-induced impairment of early porcine embryo development by promoting mitochondrial biogenesis.


Asunto(s)
Embrión de Mamíferos , Desarrollo Embrionario/efectos de los fármacos , Melatonina/farmacología , Mitocondrias , Enfermedades Mitocondriales , Rotenona/efectos adversos , Animales , Embrión de Mamíferos/embriología , Embrión de Mamíferos/patología , Mitocondrias/metabolismo , Mitocondrias/patología , Enfermedades Mitocondriales/inducido químicamente , Enfermedades Mitocondriales/embriología , Enfermedades Mitocondriales/prevención & control , Rotenona/farmacología , Porcinos
6.
Microsc Microanal ; 26(2): 287-296, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32036801

RESUMEN

Connexin 43 (CX43) is a component of gap junctions. The lack of functional CX43 induces oxidative stress, autophagy, and apoptosis in somatic cells. However, the role of CX43 in the early development of porcine embryos is still unknown. Thus, the aim of this study was to investigate the role of CX43, and its underlying molecular mechanisms, on the developmental competence of early porcine embryos. We performed CX43 knockdown by microinjecting dsRNA into parthenogenetically activated porcine parthenotes. The blastocyst development rate and the total number of cells in the blastocysts were significantly reduced by CX43 knockdown. Results from FITC-dextran assays showed that CX43 knockdown significantly increased membrane permeability. ZO-1 protein was obliterated in CX43 knockdown blastocysts. Mitochondrial membrane potential and ATP production were significantly reduced following CX43 knockdown. Reactive oxygen species (ROS) levels were significantly increased in the CX43 knockdown group compared to those in control embryos. Moreover, CX43 knockdown induced autophagy and apoptosis. Our findings indicate that CX43 is essential for the development and preimplantation of porcine embryos and maintains mitochondrial function, cell junction structure, and cell homeostasis by regulating membrane permeability, ROS generation, autophagy, and apoptosis in early embryos.


Asunto(s)
Conexina 43/genética , Desarrollo Embrionario/genética , Desarrollo Embrionario/fisiología , Mitocondrias/metabolismo , Animales , Apoptosis , Autofagia , Blastocisto/metabolismo , Técnicas de Silenciamiento del Gen , Uniones Intercelulares , Potencial de la Membrana Mitocondrial/fisiología , Oocitos , Estrés Oxidativo , Especies Reactivas de Oxígeno , Porcinos
7.
J Cell Physiol ; 234(6): 8963-8974, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30317618

RESUMEN

Spindlin 1 (SPIN1), which contains Tudor-like domains, regulates maternal transcripts via interaction with a messenger RNA (mRNA)-binding protein. SPIN1 is involved in tumorigenesis in somatic cells and is highly expressed in cancer cells. Nevertheless, the role of SPIN1 in porcine oocyte maturation remains totally unknown. To explore the function of SPIN1 in porcine oocyte maturation, knockdown, and overexpression techniques were used. SPIN1 mRNA was identified in maternal stages ranging from GV to MII. SPIN1 was localized in the cytoplasm and to chromosomes during meiosis. SPIN1 knockdown accelerated first polar body extrusion. Oocytes with overexpressed SPIN1 were arrested at the MI stage. SPIN1 depletion caused meiotic spindle defects and chromosome instability. The BUB3 signal was investigated, confirming that SPIN1 affects the stability of Bub3 mRNA as well as BUB3 expression. Further, overexpression of SPIN1 inhibited the degradation and regulation of G2/mitotic-specific cyclin-B1. In summation, SPIN1 regulates the meiotic cell cycle by modulating the activation of the spindle assembly checkpoint.


Asunto(s)
Anafase , Proteínas de Ciclo Celular/metabolismo , Metafase , Proteínas Asociadas a Microtúbulos/metabolismo , Oocitos/metabolismo , Fosfoproteínas/metabolismo , Proteínas de Unión a Poli-ADP-Ribosa/metabolismo , Huso Acromático/metabolismo , Animales , Proteína Quinasa CDC2/metabolismo , Proteínas de Ciclo Celular/genética , Células Cultivadas , Segregación Cromosómica , Femenino , Regulación del Desarrollo de la Expresión Génica , Técnicas de Maduración In Vitro de los Oocitos , Proteínas Asociadas a Microtúbulos/genética , Fosfoproteínas/genética , Proteínas de Unión a Poli-ADP-Ribosa/genética , Transducción de Señal , Sus scrofa , Factores de Tiempo
8.
Apoptosis ; 24(9-10): 718-729, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31240517

RESUMEN

Fipronil (FPN) is a widely used phenylpyrazole pesticide that can kill pests by blocking γ-aminobutyric acid (GABA)-gated chloride channels. In addition, there are lack of studies on the effects of FPN on the female mammalian gametes. In this study, porcine oocytes were used to investigate the effects of FPN on the oocyte maturation process. The results showed that the first polar body extrusion rate significantly decreased (100 µM FPN vs. control, 18.64 ± 2.95% vs. 74.90 ± 1.50%, respectively), and oocytes were arrested at the germinal vesicle stage in 100 µM FPN group. Meanwhile, the FPN caused a significant increase in reactive oxygen species (ROS) levels and severe DNA damage inside the oocytes. Furthermore, apoptosis was enhanced along with decreases in mitochondrial membrane potential, BCL-xL, and the release of cytochrome C in FPN-treated group. Additionally, low CDK1 activity and delayed cyclin B1 degradation during germinal vesicle breakdown were found in the FPN-treated group, which resulted from the activation of ATM-P53-P21 pathway. In conclusion, FPN induces apoptosis and cell cycle arrest in porcine oocyte maturation because of increased ROS levels and DNA damage. This suggests that the FPN in the environment may have potential detrimental effects on the female mammalian reproductive system.


Asunto(s)
Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Oocitos/efectos de los fármacos , Pirazoles/farmacología , Animales , Proteína Quinasa CDC2/efectos de los fármacos , Proteína Quinasa CDC2/metabolismo , Ciclina B1/efectos de los fármacos , Citocromos c/efectos de los fármacos , Citocromos c/metabolismo , Daño del ADN/efectos de los fármacos , Femenino , Técnicas In Vitro , Oocitos/citología , Oogénesis/efectos de los fármacos , Plaguicidas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Porcinos , Proteína bcl-X/efectos de los fármacos , Proteína bcl-X/metabolismo
9.
Biol Reprod ; 100(4): 907-916, 2019 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-30395161

RESUMEN

Homocysteine (Hcy) is an intermediate in the one-carbon metabolism that donates methyl groups for methylation processes involved in epigenetic gene regulation. Although poor oocyte quality in polycystic ovarian syndrome (PCOS) patients is associated with elevated Hcy concentration in serum and follicular fluid, whether Hcy directly affects oocyte quality and its mechanisms are poorly understood. Here we show that Hcy treatment impaired oocyte quality and developmental competence, indicated by significantly reduced survival rate, polar body extrusion rate, and cleavage rate. Hcy treatment resulted in mitochondrial dysfunction, with increased production of mitochondrial ROS, reduced mtDNA copy number, and the expression of 7 out of 13 mtDNA-encoded genes and 2 ribosome RNA genes, 12S rRNA and 16S rRNA. Upon Hcy treatment, the expression of one-carbon metabolic enzymes and DNMT1 was enhanced. Interestingly, DNA methyltransferase inhibitor 5'AZA rescued Hcy-induced mitochondrial dysfunction, impaired oocyte quality and developmental competence. Concurrently, expression of one-carbon metabolic enzymes and methylation status of mtDNA coding sequences were also normalized, at least partially, by 5'AZA treatment. Our findings not only extend the understanding about how Hcy induces poor oocyte quality, but also contribute to a novel angle of identifying targets for enhancing the quality of oocyte from PCOS patients.


Asunto(s)
Carbono/metabolismo , Metilación de ADN/efectos de los fármacos , ADN Mitocondrial/efectos de los fármacos , Homocisteína/farmacología , Oocitos/efectos de los fármacos , Oocitos/metabolismo , Animales , Células Cultivadas , ADN Mitocondrial/metabolismo , Metabolismo Energético/efectos de los fármacos , Epigénesis Genética/efectos de los fármacos , Femenino , Humanos , Técnicas de Maduración In Vitro de los Oocitos/métodos , Técnicas de Maduración In Vitro de los Oocitos/normas , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Oocitos/citología , Síndrome del Ovario Poliquístico/genética , Síndrome del Ovario Poliquístico/metabolismo , Síndrome del Ovario Poliquístico/patología , Control de Calidad , Porcinos , Regulación hacia Arriba/efectos de los fármacos
10.
J Cell Physiol ; 233(5): 4225-4234, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29058795

RESUMEN

Fatty acid synthase (FAS) is an important enzyme involved in the de novo synthesis of long-chain fatty acids. During development, the function of FAS in growth is greater than that in energy storage pathways; therefore, we hypothesized that knockout of FAS would affect early embryonic development owing to the induction of endoplasmic reticulum (ER) stress. In the present study, the function of FAS was studied using the CRISPR (clustered regularly interspaced short palindromic repeats)/ CRISPR-associated protein 9 (Cas9) system. Cas9 and single-guide RNA (sgRNA) were injected into parthenotes to decrease the number of FAS-positive embryos. The efficiency of knockout was assayed by DNA sequencing. We found that FAS knockout caused excessive production of reactive oxygen species (ROS). Excess ROS induced ER stress, resulting in activation of the adaptive unfolded protein response (UPR). FAS knockout caused splicing of the X-box binding protein 1 gene (XBP1) and expression of spliced XBP1 mRNA. In addition, FAS knockout caused phosphorylation of PKR-like ER kinase (PERK), and an increase in the mRNA expression of the ER stress-regulated genes, activating transcription factor 4 (ATF4), and C/EBP homologous protein (CHOP). Finally, Ca2+ was released from the ER and taken up by the mitochondria. As the ER stress became intolerable, apoptosis was initiated. These results demonstrate that FAS knockout induced ROS generation, which mediated the activation of UPR via the ER stress, ultimately leading to apoptosis induction.


Asunto(s)
Apoptosis/genética , Estrés del Retículo Endoplásmico/genética , Ácido Graso Sintasas/genética , Proteína 1 de Unión a la X-Box/genética , Factor de Transcripción Activador 4/genética , Animales , Desarrollo Embrionario/genética , Retículo Endoplásmico/genética , Femenino , Técnicas de Inactivación de Genes , Embarazo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/genética , Porcinos , Factor de Transcripción CHOP/genética , Respuesta de Proteína Desplegada/genética
11.
Microsc Microanal ; 24(1): 29-37, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29485024

RESUMEN

MicroRNA (miR)-29b plays a crucial role during somatic cell reprogramming. The aim of the current study was to explore the effects of miR-29b on the developmental competence of bovine somatic cell nuclear transfer (SCNT) embryos, as well as the underlying mechanisms of action. The expression level of miR-29b was lower in bovine SCNT embryos at the pronuclear, 8-cell, and blastocyst stages compared with in vitro fertilized embryos. In addition, miR-29b regulates the expression of DNA methyltransferases (Dnmt3a/3b and Dnmt1) in bovine SCNT embryos. We further investigated SCNT embryo developmental competence and found that miR-29b overexpression during bovine SCNT embryonic development does not improve developmental potency and downregulation inhibits developmental potency. Nevertheless, the quality of bovine SCNT embryos at the blastocyst stage improved significantly. The expression of pluripotency factors and cellular proliferation were significantly higher in blastocysts from the miR-29b overexpression group than the control and downregulation groups. In addition, outgrowth potential in blastocysts after miR-29b overexpression was also significantly greater in the miR-29b overexpression group than in the control and downregulation groups. Taken together, these results demonstrated that miR-29b plays an important role in bovine SCNT embryo development.


Asunto(s)
Blastocisto/metabolismo , Núcleo Celular/metabolismo , MicroARNs/metabolismo , Animales , Bovinos , Células Cultivadas , ADN (Citosina-5-)-Metiltransferasas/genética , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Técnica del Anticuerpo Fluorescente , Técnicas de Transferencia Nuclear , Oocitos/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
12.
Biochim Biophys Acta ; 1853(2): 317-27, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25447542

RESUMEN

Mammalian diaphanous1 (mDia1) is a homologue of Drosophila diaphanous and belongs to the Formin-homology family of proteins that catalyze actin nucleation and polymerization. Although Formin family proteins, such as Drosophila diaphanous, have been shown to be essential for cytokinesis, whether and how mDia1 functions during meiosis remain uncertain. In this study, we explored possible roles and the signaling pathway involved for mDia1 using a mouse oocyte model. mDia1 depletion reduced polar body extrusion, which may have been due to reduced cortical actin assembly. mDia1 and Profilin1 had similar localization patterns in mouse oocytes and mDia1 knockdown resulted in reduced Profilin1 expression. Depleting FMNL1, another Formin family member, resulted in reduced mDia1 expression, while RhoA inhibition did not alter mDia1 expression, which indicated that there was a FMNL1-mDia1-Profilin1 signaling pathway in mouse oocytes. Additionally, mDia1 knockdown resulted in disrupting oocyte spindle morphology, which was confirmed by aberrant p-MAPK localization. Thus, these results demonstrated indispensable roles for mDia1 in regulating mouse oocyte meiotic maturation through its effects on actin assembly and spindle organization.


Asunto(s)
Actinas/metabolismo , Proteínas Portadoras/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Meiosis , Oocitos/citología , Profilinas/metabolismo , Huso Acromático/metabolismo , Animales , Cromosomas de los Mamíferos/metabolismo , Forminas , Técnicas de Silenciamiento del Gen , Ratones Endogámicos ICR , Modelos Biológicos , Oocitos/metabolismo , Cuerpos Polares/metabolismo , Fracciones Subcelulares/metabolismo , Proteína de Unión al GTP rhoA/antagonistas & inhibidores , Proteína de Unión al GTP rhoA/metabolismo
13.
J Environ Sci (China) ; 26(2): 307-14, 2014 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-25076522

RESUMEN

We fabricated and characterized two hybrid adsorbents originated from hydrated ferric oxides (HFOs) using a polymeric anion exchanger D201 and calcite as host. The resultant adsorbents (denoted as HFO-201 and IOCCS) were employed for Sb(V) removal from water. Increasing solution pH from 3 to 9 apparently weakened Sb(V) removal by both composites, while increasing temperature from 293 to 313 K only improved Sb(V) uptake by IOCCS. HFO-201 exhibited much higher capacity for Sb(V) than for IOCCS in the absence of other anions in solution. Increasing ionic strength from 0.01 to 0.1 mol/L NaNO3 would result in a significant drop of the capacity of HFO-201 in the studied pH ranges; however, negligible effect was observed for IOCCS under similar conditions. Similarly, the competing chloride and sulfate pose more negative effect on Sb(V) adsorption by HFO-201 than by IOCCS, and the presence of silicate greatly decreased their adsorption simultaneously, while calcium ions were found to promote the adsorption of both adsorbents. XPS analysis further demonstrated that preferable Sb(V) adsorption by both hybrids was attributed to the inner sphere complexation of Sb(V) and HFO, and Ca(II) induced adsorption enhancement possibly resulted from the formation of HFO-Ca-Sb complexes. Column adsorption runs proved that Sb(V) in the synthetic water could be effectively removed from 30 microg/L to below 5 microg/L (the drinking water standard regulated by China), and the effective treatable volume of IOCCS was around 6 times as that of HFO-201, implying that HFO coatings onto calcite might be a more effective approach than immobilization inside D201.


Asunto(s)
Antimonio/aislamiento & purificación , Compuestos Férricos/química , Adsorción , Resinas de Intercambio Aniónico/química , Carbonato de Calcio/química , Concentración de Iones de Hidrógeno , Concentración Osmolar
14.
Animals (Basel) ; 14(12)2024 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-38929361

RESUMEN

Embryonic stem cells (ESCs) are remarkably undifferentiated cells that originate from the inner cell mass of the blastocyst. They possess the ability to self-renew and differentiate into multiple cell types, making them invaluable in diverse applications such as disease modeling and the creation of transgenic animals. In recent years, as agricultural practices have evolved from traditional to biological breeding, it has become clear that pluripotent stem cells (PSCs), either ESCs or induced pluripotent stem cells (iPSCs), are optimal for continually screening suitable cellular materials. However, the technologies for long-term in vitro culture or establishment of cell lines for PSCs in livestock are still immature, and research progress is uneven, which poses challenges for the application of PSCs in various fields. The establishment of a robust in vitro system for these cells is critically dependent on understanding their pluripotency maintenance mechanisms. It is believed that the combined effects of pluripotent transcription factors, pivotal signaling pathways, and epigenetic regulation contribute to maintaining their pluripotent state, forming a comprehensive regulatory network. This article will delve into the primary mechanisms underlying the maintenance of pluripotency in PSCs and elaborate on the applications of PSCs in the field of livestock.

15.
Genes (Basel) ; 15(7)2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-39062620

RESUMEN

As an RNA binding protein (RBP), DDX5 is widely involved in the regulation of various biological activities. While recent studies have confirmed that DDX5 can act as a transcriptional cofactor that is involved in the formation of gametes, few studies have investigated whether DDX5 can be used as a transcription factor to regulate the formation of primordial germ cells (PGCs). In this study, we found that DDX5 was significantly up-regulated during chicken PGC formation. Under different PGC induction models, the overexpression of DDX5 not only up-regulates PGC markers but also significantly improves the formation efficiency of primordial germ cell-like cells (PGCLC). Conversely, the inhibition of DDX5 expression can significantly inhibit both the expression of PGC markers and PGCLC formation efficiency. The effect of DDX5 on PGC formation in vivo was consistent with that seen in vitro. Interestingly, DDX5 not only participates in the formation of PGCs but also positively regulates their migration and proliferation. In the process of studying the mechanism by which DDX5 regulates PGC formation, we found that DDX5 acts as a transcription factor to bind to the promoter region of BMP4-a key gene for PGC formation-and activates the expression of BMP4. In summary, we confirm that DDX5 can act as a positive transcription factor to regulate the formation of PGCs in chickens. The obtained results not only enhance our understanding of the way in which DDX5 regulates the development of germ cells but also provide a new target for systematically optimizing the culture and induction system of PGCs in chickens in vitro.


Asunto(s)
Proteína Morfogenética Ósea 4 , Pollos , ARN Helicasas DEAD-box , Células Germinativas , Animales , Proteína Morfogenética Ósea 4/metabolismo , Proteína Morfogenética Ósea 4/genética , Células Germinativas/metabolismo , Pollos/genética , ARN Helicasas DEAD-box/genética , ARN Helicasas DEAD-box/metabolismo , Embrión de Pollo , Regulación del Desarrollo de la Expresión Génica , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proliferación Celular , Movimiento Celular/genética , Regiones Promotoras Genéticas
16.
Animals (Basel) ; 14(2)2024 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-38254471

RESUMEN

In recent years, inducing pluripotent stem cells to differentiate into functional primordial germ cells (PGCs) in vitro has become an important method of obtaining a large number of PGCs. However, the instability and low induction efficiency of the in vitro PGC induction system restrict the application of PGCs in transgenic animal production, germplasm resource conservation and other fields. In this study, we successfully established a two-step induction model of chicken PGCs in vitro, which significantly improved the formation efficiency of PGC-like cells (PGCLCs). To further improve the PGC formation efficiency in vitro, 5025 differentially expressed genes (DEGs) were obtained between embryonic stem cells (ESCs) and PGCs through RNA-seq. GO and KEGG enrichment analysis revealed that signaling pathways such as BMP4, Wnt and Notch were significantly activated during PGC formation, similar to other species. In addition, we noted that cAMP was activated during PGC formation, while MAPK was suppressed. Based on the results of our analysis, we found that the PGC formation efficiency was significantly improved after activating Wnt and inhibiting MAPK, and was lower than after activating cAMP. To sum up, in this study, we successfully established a two-step induction model of chicken PGCs in vitro with high PGC formation efficiency, which lays a theoretical foundation for further demonstrating the regulatory mechanism of PGCs and realizing their specific applications.

17.
Theriogenology ; 215: 67-77, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38011785

RESUMEN

Chicken primordial germ cells (PGCs) are important cells with significant implications in preserving genetic resources, chicken breeding and production, and basic research on genetics and development. Currently, chicken PGCs can be cultured long-term in vitro to produce single-cell clones. However, systematic exploration of the cellular characteristics of these single-cell clonal lines has yet to be conducted. In this study, single-cell clonal lines were established from male and female PGCs of Rugao Yellow Chicken and Shouguang Black Chicken, respectively, using a micropipette-based method for single-cell isolation and culture. Analysis of glycogen granule staining, mRNA expression of pluripotency marker genes (POUV, SOX2, NANOG), germ cell marker genes (DAZL, CVH), and SSEA-1, EMA-1, SOX2, C-KIT, and CVH protein expression showed positive results, indicating that PGCs maintain normal cellular properties after single-cell cloning. Furthermore, tests on proliferation ability and gene expression levels in PGC single-cell clonal lines showed high expression of the pluripotency-related genes and TERT compared to control PGCs, and PGC single-cell clonal lines demonstrated higher proliferation ability. Finally, green fluorescent protein (GFP)-PGC single-cell clonal lines were established, and it was found that these single-cell clonal lines could still migrate into the gonads of recipients, suggesting their potential for germ-line transmission. This study systematically validated the normal cellular characteristics of PGC single-cell clonal lines, indicating that they could be applied in genetic modification research on chickens.


Asunto(s)
Pollos , Células Germinativas , Animales , Masculino , Femenino , Pollos/genética , Línea Celular , Células Cultivadas , Células Germinativas/metabolismo , Proteínas Proto-Oncogénicas c-kit/metabolismo
18.
Nat Commun ; 15(1): 6317, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39060314

RESUMEN

Aerosol jet printing has the potential to fabricate fine features on various substrates due to its large stand-off distance. However, the presence of overspray and instability, particularly at high printing resolutions, has limited its widespread application. In this study, we introduce an efficient approach called annular acoustic focusing for aerosol jet printing. By determining the optimal focusing frequency (5.8 MHz) for silver nanoparticles using a particle ejection model, we achieve precise and stable printing. We also propose a modified print nozzle geometry, resulting in ultrafine traces (line width < 6 µm, overspray < 0.1 µm). Compared to printing without acoustic focusing, the line width of the traces decreases to 60 ± 5% while their conductivity increases to 180 ± 5%. Additionally, several 8 h experiments demonstrate excellent printing stability. This research opens up possibilities for the fabrication of conformal electronics with high precision and improved conductivity using aerosol jet printing.

19.
Genes (Basel) ; 15(7)2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39062741

RESUMEN

The identification of accurate gene insertion sites on chicken sex chromosomes is crucial for advancing sex control breeding materials. In this study, the intergenic region NC_006127.4 on the chicken Z chromosome and the non-repetitive sequence EE0.6 on the W chromosome were selected as potential gene insertion sites. Gene knockout vectors targeting these sites were constructed and transfected into DF-1 cells. T7E1 enzyme cleavage and luciferase reporter enzyme analyses revealed knockout efficiencies of 80.00% (16/20), 75.00% (15/20), and 75.00% (15/20) for the three sgRNAs targeting the EE0.6 site. For the three sgRNAs targeting the NC_006127.4 site, knockout efficiencies were 70.00% (14/20), 60.00% (12/20), and 45.00% (9/20). Gel electrophoresis and high-throughput sequencing were performed to detect potential off-target effects, showing no significant off-target effects for the knockout vectors at the two sites. EdU and CCK-8 proliferation assays revealed no significant difference in cell proliferation activity between the knockout and control groups. These results demonstrate that the EE0.6 and NC_006127.4 sites can serve as gene insertion sites on chicken sex chromosomes for gene editing without affecting normal cell proliferation.


Asunto(s)
Pollos , Edición Génica , Cromosomas Sexuales , Animales , Pollos/genética , Edición Génica/métodos , Cromosomas Sexuales/genética , Mutagénesis Insercional , Sistemas CRISPR-Cas , Línea Celular , Técnicas de Inactivación de Genes/métodos , Femenino , Masculino
20.
Animals (Basel) ; 14(9)2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38731386

RESUMEN

The utilization of chicken embryonic-derived pluripotent stem cell (PSC) lines is crucial in various fields, including growth and development, vaccine and protein production, and germplasm resource protection. However, the research foundation for chicken PSCs is relatively weak, and there are still challenges in establishing a stable and efficient PSC culture system. Therefore, this study aims to investigate the effects of the FGF2/ERK and WNT/ß-catenin signaling pathways, as well as different feeder layers, on the derivation and maintenance of chicken embryonic-derived PSCs. The results of this study demonstrate that the use of STO cells as feeder layers, along with the addition of FGF2, IWR-1, and XAV-939 (FIX), allows for the efficient derivation of chicken PSC-like cells. Under the FIX culture conditions, chicken PSCs express key pluripotency genes, such as POUV, SOX2, and NANOG, as well as specific proteins SSEA-1, C-KIT, and SOX2, indicating their pluripotent nature. Additionally, the embryoid body experiment confirms that these PSC-like cells can differentiate into cells of three germ layers in vitro, highlighting their potential for multilineage differentiation. Furthermore, this study reveals that chicken Eyal-Giladi and Kochav stage X blastodermal cells express genes related to the primed state of PSCs, and the FIX culture system established in this research maintains the expression of these genes in vitro. These findings contribute significantly to the understanding and optimization of chicken PSC culture conditions and provide a foundation for further exploration of the biomedical research and biotechnological applications of chicken PSCs.

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