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1.
Cell Death Dis ; 15(5): 321, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38719812

RESUMEN

RAD18, an important ubiquitin E3 ligase, plays a dual role in translesion DNA synthesis (TLS) and homologous recombination (HR) repair. However, whether and how the regulatory mechanism of O-linked N-acetylglucosamine (O-GlcNAc) modification governing RAD18 and its function during these processes remains unknown. Here, we report that human RAD18, can undergo O-GlcNAcylation at Ser130/Ser164/Thr468, which is important for optimal RAD18 accumulation at DNA damage sites. Mechanistically, abrogation of RAD18 O-GlcNAcylation limits CDC7-dependent RAD18 Ser434 phosphorylation, which in turn significantly reduces damage-induced PCNA monoubiquitination, impairs Polη focus formation and enhances UV sensitivity. Moreover, the ubiquitin and RAD51C binding ability of RAD18 at DNA double-strand breaks (DSBs) is O-GlcNAcylation-dependent. O-GlcNAcylated RAD18 promotes the binding of RAD51 to damaged DNA during HR and decreases CPT hypersensitivity. Our findings demonstrate a novel role of RAD18 O-GlcNAcylation in TLS and HR regulation, establishing a new rationale to improve chemotherapeutic treatment.


Asunto(s)
Acetilglucosamina , Proteínas de Unión al ADN , Antígeno Nuclear de Célula en Proliferación , Recombinasa Rad51 , Reparación del ADN por Recombinación , Ubiquitina-Proteína Ligasas , Humanos , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Ubiquitina-Proteína Ligasas/metabolismo , Acetilglucosamina/metabolismo , Recombinasa Rad51/metabolismo , Antígeno Nuclear de Célula en Proliferación/metabolismo , Fosforilación , Replicación del ADN , Ubiquitinación , Roturas del ADN de Doble Cadena , ADN Polimerasa Dirigida por ADN/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Daño del ADN , ADN/metabolismo , Células HEK293 , Rayos Ultravioleta , Unión Proteica , Glicosilación , Síntesis Translesional de ADN
2.
Transl Neurodegener ; 13(1): 24, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38671492

RESUMEN

BACKGROUND: Adult neurogenesis occurs in the subventricular zone (SVZ) and the subgranular zone of the dentate gyrus in the hippocampus. The neuronal stem cells in these two neurogenic niches respond differently to various physiological and pathological stimuli. Recently, we have found that the decrement of carboxypeptidase E (CPE) with aging impairs the maturation of brain-derived neurotrophic factor (BDNF) and neurogenesis in the SVZ. However, it remains unknown whether these events occur in the hippocampus, and what the role of CPE is in the adult hippocampal neurogenesis in the context of Alzheimer's disease (AD). METHODS: In vivo screening was performed to search for miRNA mimics capable of upregulating CPE expression and promoting neurogenesis in both neurogenic niches. Among these, two agomirs were further assessed for their effects on hippocampal neurogenesis in the context of AD. We also explored whether these two agomirs could ameliorate behavioral symptoms and AD pathology in mice, using direct intracerebroventricular injection or by non-invasive intranasal instillation. RESULTS: Restoration of CPE expression in the hippocampus improved BDNF maturation and boosted adult hippocampal neurogenesis. By screening the miRNA mimics targeting the 5'UTR region of Cpe gene, we developed two agomirs that were capable of upregulating CPE expression. The two agomirs significantly rescued adult neurogenesis and cognition, showing multiple beneficial effects against the AD-associated pathologies in APP/PS1 mice. Of note, noninvasive approach via intranasal delivery of these agomirs improved the behavioral and neurocognitive functions of APP/PS1 mice. CONCLUSIONS: CPE may regulate adult hippocampal neurogenesis via the CPE-BDNF-TrkB signaling pathway. This study supports the prospect of developing miRNA agomirs targeting CPE as biopharmaceuticals to counteract aging- and disease-related neurological decline in human brains.


Asunto(s)
Enfermedad de Alzheimer , Carboxipeptidasa H , Hipocampo , Trastornos de la Memoria , Neurogénesis , Regulación hacia Arriba , Animales , Neurogénesis/efectos de los fármacos , Neurogénesis/fisiología , Enfermedad de Alzheimer/genética , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Carboxipeptidasa H/genética , Carboxipeptidasa H/biosíntesis , Ratones , Trastornos de la Memoria/genética , Trastornos de la Memoria/etiología , Factor Neurotrófico Derivado del Encéfalo/biosíntesis , Factor Neurotrófico Derivado del Encéfalo/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , MicroARNs/genética , MicroARNs/biosíntesis , Masculino , Ratones Transgénicos , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad
3.
Nat Commun ; 15(1): 1785, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38413626

RESUMEN

Liver kinase B1 (LKB1), an evolutionarily conserved serine/threonine kinase, is a master regulator of the AMPK subfamily and controls cellular events such as polarity, proliferation, and energy homeostasis. Functions and mechanisms of the LKB1-AMPK axis at specific subcellular compartments, such as lysosome and mitochondria, have been established. AMPK is known to be activated at the Golgi; however, functions and regulatory mechanisms of the LKB1-AMPK axis at the Golgi apparatus remain elusive. Here, we show that TBC1D23, a Golgi-localized protein that is frequently mutated in the neurodevelopment disorder pontocerebellar hypoplasia (PCH), is specifically required for the LKB1 signaling at the Golgi. TBC1D23 directly interacts with LKB1 and recruits LKB1 to Golgi, promoting Golgi-specific activation of AMPK upon energy stress. Notably, Golgi-targeted expression of LKB1 rescues TBC1D23 deficiency in zebrafish models. Furthermore, the loss of LKB1 causes neurodevelopmental abnormalities in zebrafish, which partially recapitulates defects in TBC1D23-deficient zebrafish, and LKB1 sustains normal neuronal development via TBC1D23 interaction. Our study uncovers a regulatory mechanism of the LKB1 signaling, and reveals that a disrupted Golgi-LKB1 signaling underlies the pathogenesis of PCH.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Enfermedades Cerebelosas , Pez Cebra , Animales , Pez Cebra/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Aparato de Golgi/metabolismo
4.
Poult Sci ; 103(3): 103376, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38228059

RESUMEN

Wenchang chicken, a prized local breed in Hainan Province of China renowned for its exceptional adaptability to tropical environments and good meat quality, is deeply favored by the public. However, an insufficient understanding of its population architecture and the unclear genetic basis that governs its typical attributes have posed challenges in the protection and breeding of this precious breed. To address these gaps, we conducted whole-genome resequencing on 200 Wenchang chicken samples derived from 10 distinct strains, and we gathered data on an array of 21 phenotype traits. Population genomics analysis unveiled distinctive population structures in Wenchang chickens, primarily attributed to strong artificial selection for different feather colors. Selection sweep analysis identified a group of candidate genes, including PCDH9, DPF3, CDIN1, and SUGCT, closely linked to adaptations that enhance resilience in tropical island habitats. Genome-wide association studies (GWAS) highlighted potential candidate genes associated with diverse feather color traits, encompassing TYR, RAB38, TRPM1, GABARAPL2, CDH1, ZMIZ1, LYST, MC1R, and SASH1. Through the comprehensive analysis of high-quality genomic and phenotypic data across diverse Wenchang chicken resource groups, this study unveils the intricate genetic backgrounds and population structures of Wenchang chickens. Additionally, it identifies multiple candidate genes linked to environmental adaptation, feather color variations, and production traits. These insights not only provide genetic reference for the purification and breeding of Wenchang chickens but also broaden our understanding of the genetic basis of phenotypic diversity in chickens.


Asunto(s)
Pollos , Estudio de Asociación del Genoma Completo , Animales , Pollos/genética , Estudio de Asociación del Genoma Completo/veterinaria , Genómica , Fenotipo , Serogrupo
5.
Cell Prolif ; 57(4): e13564, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37853840

RESUMEN

'Human neural stem cells' jointly drafted and agreed upon by experts from the Chinese Society for Stem Cell Research, is the first guideline for human neural stem cells (hNSCs) in China. This standard specifies the technical requirements, test methods, test regulations, instructions for use, labelling requirements, packaging requirements, storage requirements, transportation requirements and waste disposal requirements for hNSCs, which is applicable to the quality control for hNSCs. It was originally released by the China Society for Cell Biology on 30 August 2022. We hope that publication of the guideline will facilitate institutional establishment, acceptance and execution of proper protocols, and accelerate the international standardization of hNSCs for clinical development and therapeutic applications.


Asunto(s)
Células-Madre Neurales , Trasplante de Células Madre , Humanos , Diferenciación Celular , China
6.
Nature ; 623(7989): 1070-1078, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37968394

RESUMEN

Three billion years of evolution has produced a tremendous diversity of protein molecules1, but the full potential of proteins is likely to be much greater. Accessing this potential has been challenging for both computation and experiments because the space of possible protein molecules is much larger than the space of those likely to have functions. Here we introduce Chroma, a generative model for proteins and protein complexes that can directly sample novel protein structures and sequences, and that can be conditioned to steer the generative process towards desired properties and functions. To enable this, we introduce a diffusion process that respects the conformational statistics of polymer ensembles, an efficient neural architecture for molecular systems that enables long-range reasoning with sub-quadratic scaling, layers for efficiently synthesizing three-dimensional structures of proteins from predicted inter-residue geometries and a general low-temperature sampling algorithm for diffusion models. Chroma achieves protein design as Bayesian inference under external constraints, which can involve symmetries, substructure, shape, semantics and even natural-language prompts. The experimental characterization of 310 proteins shows that sampling from Chroma results in proteins that are highly expressed, fold and have favourable biophysical properties. The crystal structures of two designed proteins exhibit atomistic agreement with Chroma samples (a backbone root-mean-square deviation of around 1.0 Å). With this unified approach to protein design, we hope to accelerate the programming of protein matter to benefit human health, materials science and synthetic biology.


Asunto(s)
Algoritmos , Simulación por Computador , Conformación Proteica , Proteínas , Humanos , Teorema de Bayes , Evolución Molecular Dirigida , Aprendizaje Automático , Modelos Moleculares , Pliegue de Proteína , Proteínas/química , Proteínas/metabolismo , Semántica , Biología Sintética/métodos , Biología Sintética/tendencias
7.
Zhongguo Zhong Yao Za Zhi ; 48(18): 4884-4892, 2023 Sep.
Artículo en Chino | MEDLINE | ID: mdl-37802830

RESUMEN

Allergic rhinitis(AR) is a common chronic inflammatory disease of the upper respiratory tract. Due to its high prevalence, high recurrence rate, and lack of a definitive cure, it is considered a global health issue by the World Health Organization. The pathogenesis of AR is complex and mainly involves B cells, helper T cells, eosinophils, basophils, macrophages, as well as the cytokines and inflammatory mediators they secrete. Clinical treatment primarily focuses on inhibiting inflammatory mediators such as histamine and leukotrienes. In recent years, active ingredients of animal-derived traditional Chinese medicine(TCM) have shown unique advantages and potential in AR treatment thanks to their high safety, specificity, selectivity, and biopotency. This study systematically reviewed the therapeutic effects and mechanisms of active ingredients and mixed extracts from animal-derived TCM, such as bovine spleen, honeycomb, bee venom, maggot, and human placenta, which have been shown by modern pharmacological research to regulate the immune function in AR, providing a reference for further exploration and clinical development of active ingredients from animal-derived TCM. Studies have found that the active ingredients from animal-derived TCM can produce definite therapeutic effects in AR by modulating multiple immune balances in the body, with great clinical prospects. However, their mechanisms of action still require further investigation, and the quality control techniques for effective ingredients need to be improved. Currently, the research on active ingredients from animal-derived TCM in China has adopted an interactive system consisting of "traditional medical experience-based research, bioinformatics and artificial intelligence predictions, and validation and development through new experimental techniques". Based on this system, animal-derived TCM can combine modern scientific and technological means to maximize the therapeutic effects of active ingredients and serve the clinical application of AR in a more efficient and innovative manner.


Asunto(s)
Medicamentos Herbarios Chinos , Poríferos , Rinitis Alérgica , Animales , Bovinos , Humanos , Medicina Tradicional China , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Inteligencia Artificial , Rinitis Alérgica/tratamiento farmacológico , Mediadores de Inflamación
8.
Int Microbiol ; 2023 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-37676442

RESUMEN

Mycobacterium tuberculosis can manipulate the host immunity through its effectors to ensure intracellular survival and colonization. Rv1043c has been identified as an effector potentially involved in M. tuberculosis pathogenicity. To explore the function of M. tuberculosis Rv1043c during infection, we overexpressed this protein in M. smegmatis, a non-pathogenic surrogate model in tuberculosis research. Here, we reported that Rv1043c enhanced mycobacterial survival and down-regulated the release of pro-inflammatory cytokines in macrophages and mice. In addition, Rv1043c inhibited the activation of MAPK and NF-κB signaling by preventing the phosphorylation of TAK1 indirectly. In conclusion, these data suggest that Rv1043c regulates the immune response and enhances the survival of recombinant M. smegmatis in vitro and in vivo.

9.
Cell Biosci ; 13(1): 123, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37400935

RESUMEN

BACKGROUND: Maintaining homeostasis of Ca2+ stores in the endoplasmic reticulum (ER) is crucial for proper Ca2+ signaling and key cellular functions. Although Ca2+ depletion has been known to cause ER stress which in turn activates the unfolded protein response (UPR), how UPR sensors/transducers respond to excess Ca2+ when ER stores are overloaded remain largely unclear. RESULTS: Here, we report for the first time that overloading of ER Ca2+ can directly sensitize the IRE1α-XBP1 axis. The overloaded ER Ca2+ in TMCO1-deficient cells can cause BiP dissociation from IRE1α, promote the dimerization and stability of the IRE1α protein, and boost IRE1α activation. Intriguingly, attenuation of the over-activated IRE1α-XBP1s signaling by a IRE1α inhibitor can cause a significant cell death in TMCO1-deficient cells. CONCLUSIONS: Our data establish a causal link between excess Ca2+ in ER stores and the selective activation of IRE1α-XBP1 axis, underscoring an unexpected role of overload of ER Ca2+ in IRE1α activation and in preventing cell death.

10.
Virulence ; 14(1): 2223394, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37332205

RESUMEN

As a member of the pattern recognition receptors (PRRs) involving in the innate immune system, Toll-like receptors (TLRs) can sense a wide range of microbial pathogens and combat infections by producing antimicrobial products, inflammatory cytokines, and chemokines. All TLRs, with the exception of TLR3, activate a signalling cascade via the myeloid differentiation primary response gene 88 (MyD88). Therefore, the activation of MyD88-dependent signalling pathway must be finely controlled. Herein, we identified that cyclin-dependent kinase 5 (CDK5) negatively regulated TLR-MyD88 signalling pathway by targeting MyD88. Overexpression of CDK5 reduced the production of interferons (IFNs), while a deficiency in CDK5 increased the expression of IFNs in response to vesicular stomatitis virus (VSV) infection. Mechanistically, CDK5 suppressed the formation of MyD88 homodimers, resulting in the attenuated production of IFNs induced by VSV infection. Surprisingly, its kinase activity does not play a role in this process. Therefore, CDK5 can act as an internal regulator to prevent excessive production of IFNs by restricting TLR-MyD88-induced activation of antiviral innate immunity in A549 cells.


Asunto(s)
Factor 88 de Diferenciación Mieloide , Virosis , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Diferenciación Celular , Quinasa 5 Dependiente de la Ciclina/metabolismo , Inmunidad Innata , Factor 88 de Diferenciación Mieloide/genética , Receptores Toll-Like , Virosis/inmunología
11.
Cell Biosci ; 13(1): 10, 2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36647159

RESUMEN

The dynamic changes in chromatin conformation alter the organization and structure of the genome and further regulate gene transcription. Basically, the chromatin structure is controlled by reversible, enzyme-catalyzed covalent modifications to chromatin components and by noncovalent ATP-dependent modifications via chromatin remodeling complexes, including switch/sucrose nonfermentable (SWI/SNF), inositol-requiring 80 (INO80), imitation switch (ISWI) and chromodomain-helicase DNA-binding protein (CHD) complexes. Recent studies have shown that chromatin remodeling is essential in different stages of postnatal and adult neurogenesis. Chromatin deregulation, which leads to defects in epigenetic gene regulation and further pathological gene expression programs, often causes a wide range of pathologies. This review first gives an overview of the regulatory mechanisms of chromatin remodeling. We then focus mainly on discussing the physiological functions of chromatin remodeling, particularly histone and DNA modifications and the four classes of ATP-dependent chromatin-remodeling enzymes, in the central and peripheral nervous systems under healthy and pathological conditions, that is, in neurodegenerative disorders. Finally, we provide an update on the development of potent and selective small molecule modulators targeting various chromatin-modifying proteins commonly associated with neurodegenerative diseases and their potential clinical applications.

12.
Genomics ; 114(6): 110518, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36347326

RESUMEN

The Muscovy duck (Cairina moschata) is an economically important poultry species, which is susceptible to fatty liver. Thus, the Muscovy duck may serve as an excellent candidate animal model of non-alcoholic fatty liver disease. However, the mechanisms underlying fatty liver development in this species are poorly understood. In this study, we report a chromosome-level genome assembly of the Muscovy duck, with a contig N50 of 11.8 Mb and scaffold N50 of 83.16 Mb. The susceptibility of Muscovy duck to fatty liver was mainly attributed to weak lipid catabolism capabilities (fatty acid ß-oxidation and lipolysis). Furthermore, conserved noncoding elements (CNEs) showing accelerated evolution contributed to fatty liver formation by down-regulating the expression of genes involved in hepatic lipid catabolism. We propose that the susceptibility of Muscovy duck to fatty liver is an evolutionary by-product. In conclusion, this study revealed the potential mechanisms underlying the susceptibility of Muscovy duck to fatty liver.


Asunto(s)
Hígado Graso , Humanos , Hígado Graso/genética , Hígado Graso/veterinaria , Cromosomas , Lípidos
13.
Cell Death Dis ; 13(8): 674, 2022 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-35927240

RESUMEN

Transmembrane of coiled-coil domains 1 (TMCO1) plays an important role in maintaining homeostasis of calcium (Ca2+) stores in the endoplasmic reticulum (ER). TMCO1-defect syndrome shares multiple features with human cerebro-facio-thoracic (CFT) dysplasia, including abnormal corpus callosum (CC). Here, we report that TMCO1 is required for the normal development of CC through sustaining Ca2+ homeostasis. Tmco1-/- mice exhibit severe agenesis of CC with stalled white matter fiber bundles failing to pass across the midline. Mechanistically, the excessive Ca2+ signals caused by TMCO1 deficiency result in upregulation of FGFs and over-activation of ERK, leading to an excess of glial cell migration and overpopulated midline glia cells in the indusium griseum which secretes Slit2 to repulse extension of the neural fiber bundles before crossing the midline. Supportingly, using the clinical MEK inhibitors to attenuate the over-activated FGF/ERK signaling can significantly improve the CC formation in Tmco1-/- brains. Our findings not only unravel the underlying mechanism of abnormal CC in TMCO1 defect syndrome, but also offer an attractive prevention strategy to relieve the related agenesis of CC in patients.


Asunto(s)
Cuerpo Calloso , Discapacidad Intelectual , Animales , Canales de Calcio/metabolismo , Cuerpo Calloso/metabolismo , Retículo Endoplásmico/metabolismo , Quinasas MAP Reguladas por Señal Extracelular , Homeostasis , Humanos , Sistema de Señalización de MAP Quinasas , Ratones , Neurogénesis
14.
Front Cell Neurosci ; 16: 852002, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35846567

RESUMEN

Most of the neurodegenerative diseases and aging are associated with reactive oxygen species (ROS) or other intracellular damaging agents that challenge the genome integrity of the neurons. As most of the mature neurons stay in G0/G1 phase, replication-uncoupled DNA repair pathways including BER, NER, SSBR, and NHEJ, are pivotal, efficient, and economic mechanisms to maintain genomic stability without reactivating cell cycle. In these progresses, polymerases are prominent, not only because they are responsible for both sensing and repairing damages, but also for their more diversified roles depending on the cell cycle phase and damage types. In this review, we summarized recent knowledge on the structural and biochemical properties of distinct polymerases, including DNA and RNA polymerases, which are known to be expressed and active in nervous system; the biological relevance of these polymerases and their interactors with neuronal degeneration would be most graphically illustrated by the neurological abnormalities observed in patients with hereditary diseases associated with defects in DNA repair; furthermore, the vicious cycle of the trinucleotide repeat (TNR) and impaired DNA repair pathway is also discussed. Unraveling the mechanisms and contextual basis of the role of the polymerases in DNA damage response and repair will promote our understanding about how long-lived postmitotic cells cope with DNA lesions, and why disrupted DNA repair contributes to disease origin, despite the diversity of mutations in genes. This knowledge may lead to new insight into the development of targeted intervention for neurodegenerative diseases.

15.
Int J Biol Sci ; 18(11): 4513-4531, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35864958

RESUMEN

During oocyte growth, various epigenetic modifications are gradually established, accompanied by accumulation of large amounts of mRNAs and proteins. However, little is known about the relationship between epigenetic modifications and meiotic progression. Here, by using Gdf9-Cre to achieve oocyte-specific ablation of Ehmt2 (Euchromatic-Histone-Lysine-Methyltransferase 2) from the primordial follicle stage, we found that female mutant mice were infertile. Oocyte-specific knockout of Ehmt2 caused failure of homologous chromosome separation independent of persistently activated SAC during the first meiosis. Further studies revealed that lacking maternal Ehmt2 affected the transcriptional level of Ccnb3, while microinjection of exogenous Ccnb3 mRNA could partly rescue the failure of homologous chromosome segregation. Of particular importance was that EHMT2 regulated ccnb3 transcriptions by regulating CTCF binding near ccnb3 gene body in genome in oocytes. In addition, the mRNA level of Ccnb3 significantly decreased in the follicles microinjected with Ctcf siRNA. Therefore, our findings highlight the novel function of maternal EHMT2 on the metaphase I-to-anaphase I transition in mouse oocytes: regulating the transcription of Ccnb3.


Asunto(s)
Segregación Cromosómica , Meiosis , Anafase , Animales , Femenino , Meiosis/genética , Ratones , Oocitos/metabolismo , ARN Mensajero/metabolismo
16.
Biomedicines ; 10(5)2022 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-35625884

RESUMEN

Bone morphogenetic protein (BMP) signaling has been shown to be intimately associated with adult neurogenesis in the subventricular zone (SVZ) and subgranular zone (SGZ). Adult neurogenesis declines in aging rodents and primates. However, the role of BMP signaling in the age-related neurogenesis decline remains elusive and the effect of BMP4 on adult SVZ neurogenesis remains controversial. Here, the expression of BMP4 and its canonical effector phosphorylated-Smad1/5/8 (p-Smad1/5/8) in the murine SVZ and SGZ were found to be increased markedly with age. We identified Id3 as a major target of BMP4 in neuronal stem cells (NSCs) of both neurogenic regions, which exhibited a similar increase during aging. Intracerebroventricular infusion of BMP4 activated Smad1/5/8 phosphorylation and upregulated Id3 expression, which further restrained NeuroD1, leading to attenuated neurogenesis in both neurogenic regions and defective differentiation in the SGZ. Conversely, noggin, a potent inhibitor of BMP4, demonstrated opposing effects. In support of this, BMP4 treatment or lentiviral overexpression of Id3 resulted in decreased NeuroD1 protein levels in NSCs of both neurogenic regions and significantly inhibited neurogenesis. Thus, our findings revealed that the increased BMP4 signaling with age inhibited adult neurogenesis in both SVZ and SGZ, which may be attributed at least in part, to the changes in the Id3-NeuroD1 axis.

17.
J Biol Chem ; 298(5): 101861, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35339488

RESUMEN

DNA polymerase eta (Pol η) is a eukaryotic member of the Y-family of DNA polymerase involved in translesion DNA synthesis and genome mutagenesis. Recently, several translesion DNA synthesis polymerases have been found to function in repair of DNA double-strand breaks (DSBs). However, the role of Pol η in promoting DSB repair remains to be well defined. Here, we demonstrated that Pol η could be targeted to etoposide (ETO)-induced DSBs and that depletion of Pol η in cells causes increased sensitivity to ETO. Intriguingly, depletion of Pol η also led to a nonhomologous end joining repair defect in a catalytic activity-independent manner. We further identified the scaffold protein Kap1 as a novel interacting partner of Pol η, the depletion of which resulted in impaired formation of Pol η and Rad18 foci after ETO treatment. Additionally, overexpression of Kap1 failed to restore Pol η focus formation in Rad18-deficient cells after ETO treatment. Interestingly, we also found that Kap1 bound to Rad18 in a Pol η-dependent manner, and moreover, depletion of Kap1 led to a significant reduction in Rad18-Pol η association, indicating that Kap1 forms a ternary complex with Rad18 and Pol η to stabilize Rad18-Pol η association. Our findings demonstrate that Kap1 could regulate the role of Pol η in ETO-induced DSB repair via facilitating Rad18 recruitment and stabilizing Rad18-Pol η association.


Asunto(s)
Reparación del ADN por Unión de Extremidades , Proteínas de Unión al ADN , ADN Polimerasa Dirigida por ADN , Ubiquitina-Proteína Ligasas , Daño del ADN , Reparación del ADN , Proteínas de Unión al ADN/metabolismo , ADN Polimerasa Dirigida por ADN/genética , ADN Polimerasa Dirigida por ADN/metabolismo , Etopósido/farmacología , Factores de Transcripción/genética , Ubiquitina-Proteína Ligasas/metabolismo
18.
Orthop Surg ; 14(4): 644-651, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35293669

RESUMEN

As skeletal muscle is one of the largest organs in the body, its damage can directly reflect a decline in somatic function, thus, further affecting daily life and health. Inflammation is a prerequisite for the repair of injured skeletal muscles. Chronic inflammation induced by inadequate repair in skeletal muscle aggravates tissue injury. Exosomes regulate inflammatory responses to facilitate the repair of skeletal muscle injury. Moreover, exosomal miR-223 with high specificity is the most abundant miRNA in peripheral blood and regarded as biomarkers for inflammation post skeletal muscle injury, which warrants further investigation. Available studies have demonstrated that exosomal miR-223 negatively correlates with TNF-α levels in serum and regulates the canonical inflammatory NF-κB signaling pathway. miR-223 is a negative feedback regulator with great potential for adjusting inflammatory imbalance and promoting skeletal muscle repair. The research on the regulation of negative feedback factors in the inflammatory signaling pathway is essential in biology and medicine. Therefore, this review mainly elaborates the formation, heterogeneity and markers of exosomes and points out exosomal miR-223 as a beneficial role in chronic skeletal muscle inflammation and can be expected to be a potential therapeutic target for skeletal muscle damage.


Asunto(s)
Exosomas , MicroARNs , Animales , Exosomas/metabolismo , Humanos , Inflamación/metabolismo , MicroARNs/metabolismo , Músculo Esquelético , FN-kappa B/metabolismo
19.
Proc Natl Acad Sci U S A ; 119(6)2022 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-35121659

RESUMEN

Ca2+ release from the endoplasmic reticulum (ER) is an essential event in the modulation of Ca2+ homeostasis, which is coordinated by multiple biological processes, ranging from cell proliferation to apoptosis. Deregulated Ca2+ homeostasis is linked with various cancer hallmarks; thus, uncovering the mechanisms underlying Ca2+ homeostasis dynamics may lead to new anticancer treatment strategies. Here, we demonstrate that a reported Ca2+-channel protein TMCO1 (transmembrane and coiled-coil domains 1) is overexpressed in colon cancer tissues at protein levels but not at messenger RNA levels in colon cancer. Further study revealed that TMCO1 is a substrate of ER-associated degradation E3 ligase Gp78. Intriguingly, Gp78-mediated TMCO1 degradation at K186 is under the control of the iASPP (inhibitor of apoptosis-stimulating protein of p53) oncogene. Mechanistically, iASPP robustly reduces ER Ca2+ stores, mainly by competitively binding with Gp78 and interfering with Gp78-mediated TMCO1 degradation. A positive correlation between iASPP and TMCO1 proteins is further validated in human colon tissues. Inhibition of iASPP-TMCO1 axis promotes cytosolic Ca2+ overload-induced apoptotic cell death, reducing tumor growth both in vitro and in vivo. Thus, iASPP-TMCO1 represents a promising anticancer treatment target by modulating Ca2+ homeostasis.


Asunto(s)
Canales de Calcio/metabolismo , Calcio/metabolismo , Proliferación Celular/fisiología , Resistencia a Medicamentos/fisiología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias/metabolismo , Receptores del Factor Autocrino de Motilidad/metabolismo , Proteínas Represoras/metabolismo , Animales , Apoptosis/fisiología , Línea Celular Tumoral , Retículo Endoplásmico/metabolismo , Degradación Asociada con el Retículo Endoplásmico/fisiología , Células HCT116 , Células HT29 , Homeostasis , Humanos , Ratones , Ratones Desnudos
20.
Zhongguo Gu Shang ; 35(1): 38-42, 2022 Jan 25.
Artículo en Chino | MEDLINE | ID: mdl-35130597

RESUMEN

OBJECTIVE: To analyze the relationship between hemoglobin(Hb) level on admission and survival prognosis of patients with hip fracture. METHODS: From February 2016 to October 2018, 249 elderly patients with hip fracture were surgically treated including 62 males and 187 females;the age ranged from 60 to 91(73.67±10.52) years;the time from injury to operation was (6.79±2.27) d. The clinical and laboratory examination results were collected. The Hb level at admission and the mortality at 30, 90, 180 and 360 days after operation were observed. According to the Hb level at admission, the patients were divided into Hb<120 g/L and Hb≥120 g/L groups. The survival conditions of the two groups at 30, 90, 180 and 360 days after operation were compared and analyzed. Logistic regression was used to analyze the effect of Hb level on death 30, 90, 180 and 360 days after operation. RESULTS: The mortality rates at 30, 90, 180 and 360 days after operation were 5.22%, 9.24%, 16.87% and 20.48% respectively. The level of Hb at admission was a risk factor for prognosis and death 30, 90, 180 and 360 days after operation(P<0.05). The OR(95% CI) were 2.431(1.475-4.006), 2.625(1.468-4.695), 2.276(1.320-3.925) and 2.082(1.221-3.551) respectively. CONCLUSION: The level of Hb at admission can affect the survival and prognosis of elderly patients with hip fracture. We should further study how to manage the level of Hb before operation.


Asunto(s)
Fracturas de Cadera , Anciano , Anciano de 80 o más Años , Femenino , Hemoglobinas/análisis , Fracturas de Cadera/cirugía , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Factores de Riesgo
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