scholarly journals The molecular and epigenetic mechanisms of innate lymphoid cell (ILC) memory and its relevance for asthma

2021 ◽  
Vol 218 (7) ◽  
Author(s):  
Mukesh Verma ◽  
Lidia Michalec ◽  
Anand Sripada ◽  
Jerome McKay ◽  
Kapil Sirohi ◽  
...  
Keyword(s):  
Adoptive Transfer ◽  
Essential Role ◽  
Gene Knockout ◽  
Gene Repression ◽  
Epigenetic Mechanisms ◽  
Epigenetic Landscape ◽  
Innate Lymphoid Cell ◽  
Repetitive Exposure ◽  
Altered Gene ◽  
Effector Pathways

Repetitive exposure of Rag1−/− mice to the Alternaria allergen extract generated a form of memory that elicited an asthma-like response upon a subthreshold recall challenge 3–15 wk later. This memory was associated with lung ICOS+ST2+ ILC2s. Genetic, pharmacologic, and antibody-mediated inhibition and adoptive transfer established an essential role for ILC2s in memory-driven asthma. ATAC-seq demonstrated a distinct epigenetic landscape of memory ILC2s and identified Bach2 and AP1 (JunD and Fosl2) motifs as major drivers of altered gene accessibility. scRNA-seq, gene knockout, and signaling studies suggest that repetitive allergenic stress induces a gene repression program involving Nr4a2, Zeb1, Bach2, and JunD and a preparedness program involving Fhl2, FosB, Stat6, Srebf2, and MPP7 in memory ILC2s. A mutually regulated balance between these two programs establishes and maintains memory. The preparedness program (e.g., Fhl2) can be activated with a subthreshold cognate stimulation, which down-regulates repressors and activates effector pathways to elicit the memory-driven phenotype.

scholarly journals Biodegradation of Bisphenol A by Sphingobium sp. YC-JY1 and the Essential Role of Cytochrome P450 Monooxygenase

2020 ◽  
Vol 21 (10) ◽  
pp. 3588
Author(s):  
Yang Jia ◽  
Adel Eltoukhy ◽  
Junhuan Wang ◽  
Xianjun Li ◽  
Thet Su Hlaing ◽  
...  
Keyword(s):  
Cytochrome P450 ◽  
Bisphenol A ◽  
Essential Role ◽  
Gene Knockout ◽  
Polluted Soil ◽  
Optimal Temperature ◽  
P450 Monooxygenase ◽  
Soil Microbial ◽  
Application Potential

Bisphenol A (BPA) is a widespread pollutant threatening the ecosystem and human health. An effective BPA degrader YC-JY1 was isolated and identified as Sphingobium sp. The optimal temperature and pH for the degradation of BPA by strain YC-JY1 were 30 °C and 6.5, respectively. The biodegradation pathway was proposed based on the identification of the metabolites. The addition of cytochrome P450 (CYP) inhibitor 1-aminobenzotriazole significantly decreased the degradation of BPA by Sphingobium sp. YC-JY1. Escherichia coli BL21 (DE3) cells harboring pET28a-bisdAB achieved the ability to degrade BPA. The bisdB gene knockout strain YC-JY1ΔbisdB was unable to degrade BPA indicating that P450bisdB was an essential initiator of BPA metabolism in strain YC-JY1. For BPA polluted soil remediation, strain YC-JY1 considerably stimulated biodegradation of BPA associated with the soil microbial community. These results point out that strain YC-JY1 is a promising microbe for BPA removal and possesses great application potential.

scholarly journals Protective Mechanisms Induced by a Japanese Encephalitis Virus DNA Vaccine: Requirement for Antibody but Not CD8+Cytotoxic T-Cell Responses

2001 ◽  
Vol 75 (23) ◽  
pp. 11457-11463 ◽  
Author(s):  
Chien-Hsiung Pan ◽  
Hsin-Wei Chen ◽  
Hui-Wen Huang ◽  
Mi-Hua Tao
Keyword(s):  
T Cells ◽  
T Cell ◽  
Japanese Encephalitis Virus ◽  
Dna Vaccine ◽  
Japanese Encephalitis ◽  
Adoptive Transfer ◽  
Knockout Mice ◽  
Gene Knockout ◽  
Dna Vaccination ◽  
Gene Knockout Mice

ABSTRACT We have previously shown that a plasmid (pE) encoding the Japanese encephalitis virus (JEV) envelope (E) protein conferred a high level of protection against a lethal viral challenge. In the present study, we used adoptive transfer experiments and gene knockout mice to demonstrate that the DNA-induced E-specific antibody alone can confer protection in the absence of cytotoxic T-lymphocyte (CTL) functions. Plasmid pE administered by either intramuscular or gene gun injection produced significant E-specific antibodies, helper T (Th)-cell proliferative responses, and CTL activities. Animals receiving suboptimal DNA vaccination produced low titers of anti-E antibodies and were only partially or not protected from viral challenge, indicating a strong correlation between anti-E antibodies and the protective capacity. This observation was confirmed by adoptive transfer experiments. Intravenous transfer of E-specific antisera but not crude or T-cell-enriched immune splenocytes to sublethally irradiated hosts conferred protection against a lethal JEV challenge. Furthermore, experiments with gene knockout mice showed that DNA vaccination did not induce anti-E titers and protective immunity in Igμ−/−and I-Aβ−/− mice, whereas in CD8α−/−mice the pE-induced antibody titers and protective rate were comparable to those produced in the wild-type mice. Taken together, these results demonstrate that the anti-E antibody is the most critical protective component in this JEV challenge model and that production of anti-E antibody by pE DNA vaccine is dependent on the presence of CD4+ T cells but independent of CD8+ T cells.

scholarly journals Cytoplasmic accumulation of NCoR in malignant melanoma: consequences of altered gene repression and prognostic significance

Oncotarget ◽  
2015 ◽  
Vol 6 (11) ◽  
pp. 9284-9294 ◽  
Author(s):  
Fernando Gallardo ◽  
Andreina Padrón ◽  
Ricard Garcia-Carbonell ◽  
Cristina Rius ◽  
Abel González-Perez ◽  
...  
Keyword(s):  
Malignant Melanoma ◽  
Prognostic Significance ◽  
Gene Repression ◽  
Cytoplasmic Accumulation ◽  
Altered Gene

scholarly journals CRISPR/Cas9-Mediated Chicken TBK1 Gene Knockout and Its Essential Role in STING-Mediated IFN-β Induction in Chicken Cells

2019 ◽  
Vol 9 ◽  
Author(s):  
Yuqiang Cheng ◽  
Minxiang Lun ◽  
Yunxia Liu ◽  
Hengan Wang ◽  
Yaxian Yan ◽  
...  
Keyword(s):  
Essential Role ◽  
Gene Knockout ◽  
Tbk1 Gene

scholarly journals Methyl Donor Nutrients in Chronic Kidney Disease: Impact on the Epigenetic Landscape

2019 ◽  
Vol 149 (3) ◽  
pp. 372-380 ◽  
Author(s):  
Denise Mafra ◽  
Marta Esgalhado ◽  
Natalia A Borges ◽  
Ludmila F M F Cardozo ◽  
Milena B Stockler-Pinto ◽  
...  
Keyword(s):  
Gene Expression ◽  
Chronic Kidney Disease ◽  
Dna Methylation ◽  
Kidney Disease ◽  
Carbon Metabolism ◽  
Epigenetic Landscape ◽  
Methyl Donor ◽  
Disease Impact ◽  
One Carbon Metabolism ◽  
Altered Gene

ABSTRACT Epigenetic alterations, such as those linked to DNA methylation, may potentially provide molecular explanations for complications associated with altered gene expression in illnesses, such as chronic kidney disease (CKD). Although both DNA hypo- and hypermethylation have been observed in the uremic milieu, this remains only a single aspect of the epigenetic landscape and, thus, of any biochemical dysregulation associated with CKD. Nevertheless, the role of uremia-promoting alterations on the epigenetic landscape regulating gene expression is still a novel and scarcely studied field. Although few studies have actually reported alterations of DNA methylation via methyl donor nutrient intake, emerging evidence indicates that nutritional modification of the microbiome can affect one-carbon metabolism and the capacity to methylate the genome in CKD. In this review, we discuss the nutritional modifications that may affect one-carbon metabolism and the possible impact of methyl donor nutrients on the microbiome, CKD, and its phenotype.

scholarly journals Genetic disruption of Plasmodium falciparum Merozoite surface antigen 180 (PfMSA180) suggests an essential role during parasite egress from erythrocytes

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Vanndita Bahl ◽  
Kritika Chaddha ◽  
Syed Yusuf Mian ◽  
Anthony A. Holder ◽  
Ellen Knuepfer ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Surface Antigen ◽  
Essential Role ◽  
Gene Knockout ◽  
Intervention Strategy ◽  
Merozoite Surface Antigen ◽  
Erythrocytic Cycle ◽  
And Function ◽  
Parasite Egress

AbstractPlasmodium falciparum, the parasite responsible for severe malaria, develops within erythrocytes. Merozoite invasion and subsequent egress of intraerythrocytic parasites are essential for this erythrocytic cycle, parasite survival and pathogenesis. In the present study, we report the essential role of a novel protein, P. falciparum Merozoite Surface Antigen 180 (PfMSA180), which is conserved across Plasmodium species and recently shown to be associated with the P. vivax merozoite surface. Here, we studied MSA180 expression, processing, localization and function in P. falciparum blood stages. Initially we examined its role in invasion, a process mediated by multiple ligand-receptor interactions and an attractive step for targeting with inhibitory antibodies through the development of a malaria vaccine. Using antibodies specific for different regions of PfMSA180, together with a parasite containing a conditional pfmsa180-gene knockout generated using CRISPR/Cas9 and DiCre recombinase technology, we demonstrate that this protein is unlikely to play a crucial role in erythrocyte invasion. However, deletion of the pfmsa180 gene resulted in a severe egress defect, preventing schizont rupture and blocking the erythrocytic cycle. Our study highlights an essential role of PfMSA180 in parasite egress, which could be targeted through the development of a novel malaria intervention strategy.

scholarly journals Microtubule end tethering of a processive kinesin-8 motor Kif18b is required for spindle positioning

2018 ◽  
Vol 217 (7) ◽  
pp. 2403-2416 ◽  
Author(s):  
Toni McHugh ◽  
Agata A. Gluszek ◽  
Julie P.I. Welburn
Keyword(s):  
Cell Division ◽  
Mitotic Spindle ◽  
Essential Role ◽  
Gene Knockout ◽  
Spindle Orientation ◽  
Binding Region ◽  
Spindle Positioning ◽  
Astral Microtubule ◽  
In Vitro Reconstitution

Mitotic spindle positioning specifies the plane of cell division during anaphase. Spindle orientation and positioning are therefore critical to ensure symmetric division in mitosis and asymmetric division during development. The control of astral microtubule length plays an essential role in positioning the spindle. In this study, using gene knockout, we show that the kinesin-8 Kif18b controls microtubule length to center the mitotic spindle at metaphase. Using in vitro reconstitution, we reveal that Kif18b is a highly processive plus end–directed motor that uses a C-terminal nonmotor microtubule-binding region to accumulate at growing microtubule plus ends. This region is regulated by phosphorylation to spatially control Kif18b accumulation at plus ends and is essential for Kif18b-dependent spindle positioning and regulation of microtubule length. Finally, we demonstrate that Kif18b shortens microtubules by increasing the catastrophe rate of dynamic microtubules. Overall, our work reveals that Kif18b uses its motile properties to reach microtubule ends, where it regulates astral microtubule length to ensure spindle centering.

scholarly journals Microtubule end tethering of a processive Kinesin-8 motor Kif18b is required for spindle positioning

2018 ◽  
Author(s):  
Toni McHugh ◽  
Agata Gluszek-Kustusz ◽  
Julie P.I. Welburn
Keyword(s):  
Cell Division ◽  
Mitotic Spindle ◽  
Essential Role ◽  
Gene Knockout ◽  
Integrated Approach ◽  
Spindle Orientation ◽  
Binding Region ◽  
Spindle Positioning ◽  
Symmetric Division ◽  
Astral Microtubule

AbstractMitotic spindle positioning specifies the plane of cell division during anaphase. Spindle orientation and positioning is therefore critical to ensure symmetric division in mitosis and asymmetric division during development. The control of astral microtubule length plays an essential role in positioning the spindle. Here we show using gene knockout that the Kinesin-8 Kif18b controls microtubule length to center the mitotic spindle at metaphase. Using an integrated approach, we reveal that Kif18b is a highly processive plus end-directed motor that uses a C-terminal non-motor microtubule-binding region to accumulate at growing microtubule plus ends. This region is regulated by phosphorylation to spatially control Kif18b accumulation at plus ends and is essential for Kif18b-dependent spindle positioning and regulation of microtubule length. Finally, we demonstrate that Kif18b shortens microtubules by increasing the catastrophe rate of dynamic microtubules. Overall, our work reveals that Kif18b utilizes its motile properties to reach microtubule ends where it regulates astral microtubule length to ensure spindle centering.

scholarly journals SUN5 Interacting With Nesprin3 Plays an Essential Role in Sperm Head-to-Tail Linkage: Research on Sun5 Gene Knockout Mice

2021 ◽  
Vol 9 ◽  
Author(s):  
Yunfei Zhang ◽  
Linfei Yang ◽  
Lihua Huang ◽  
Gang Liu ◽  
Xinmin Nie ◽  
...  
Keyword(s):  
Molecular Mechanism ◽  
Nuclear Membrane ◽  
Knockout Mice ◽  
Essential Role ◽  
Gene Knockout ◽  
Bioinformatic Analysis ◽  
Sperm Head ◽  
Linc Complex ◽  
Absolute Quantitation ◽  
Gene Knockout Mice

Acephalic spermatozoa syndrome is a rare genetic and reproductive disease. Recent studies have shown that approximately 33–47% of patients with acephalic spermatozoa syndrome have SUN5 mutations, but the molecular mechanism underlying this phenomenon has not been elucidated. In this study, we generated Sun5 knockout mice and found that the head-to-tail linkage was broken in Sun5–/– mice, which was similar to human acephalic spermatozoa syndrome. Furthermore, ultrastructural imaging revealed that the head-tail coupling apparatus (HTCA) and the centrosome were distant from the nucleus at steps 9–10 during spermatid elongation. With the manchette disappearing at steps 13–14, the head and the tail segregated. To explore the molecular mechanism underlying this process, bioinformatic analysis was performed and showed that Sun5 may interact with Nesprin3. Further coimmunoprecipitation (Co-IP) and immunofluorescence assays confirmed that Sun5 and Nesprin3 were indeed bona fide interaction partners that formed the linker of the nucleoskeleton and cytoskeleton (LINC) complex participating in the connection of the head and tail of spermatozoa. Nesprin3 was located posterior and anterior to the nucleus during spermiogenesis in wild-type mice, whereas it lost its localization at the implantation fossa of the posterior region in Sun5–/– mice. Without correct localization of Nesprin3 at the nuclear membrane, the centrosome, which is the originator of the flagellum, was distant from the nucleus, which led to the separation of the head and tail. In addition, isobaric tag for relative and absolute quantitation results showed that 47 proteins were upregulated, and 56 proteins were downregulated, in the testis in Sun5–/– mice, and the downregulation of spermatogenesis-related proteins (Odf1 and Odf2) may also contribute to the damage to the spermatozoa head-to-tail linkage. Our findings suggested that Sun5 is essential for the localization of Nesprin3 at the posterior nuclear membrane, which plays an essential role in the sperm head-tail connection.

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