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1.
Cell ; 186(1): 112-130.e20, 2023 01 05.
Article in English | MEDLINE | ID: mdl-36580912

ABSTRACT

How SARS-CoV-2 penetrates the airway barrier of mucus and periciliary mucins to infect nasal epithelium remains unclear. Using primary nasal epithelial organoid cultures, we found that the virus attaches to motile cilia via the ACE2 receptor. SARS-CoV-2 traverses the mucus layer, using motile cilia as tracks to access the cell body. Depleting cilia blocks infection for SARS-CoV-2 and other respiratory viruses. SARS-CoV-2 progeny attach to airway microvilli 24 h post-infection and trigger formation of apically extended and highly branched microvilli that organize viral egress from the microvilli back into the mucus layer, supporting a model of virus dispersion throughout airway tissue via mucociliary transport. Phosphoproteomics and kinase inhibition reveal that microvillar remodeling is regulated by p21-activated kinases (PAK). Importantly, Omicron variants bind with higher affinity to motile cilia and show accelerated viral entry. Our work suggests that motile cilia, microvilli, and mucociliary-dependent mucus flow are critical for efficient virus replication in nasal epithelia.


Subject(s)
COVID-19 , Respiratory System , SARS-CoV-2 , Humans , Cilia/physiology , Cilia/virology , COVID-19/virology , Respiratory System/cytology , Respiratory System/virology , SARS-CoV-2/physiology , Microvilli/physiology , Microvilli/virology , Virus Internalization , Epithelial Cells/physiology , Epithelial Cells/virology
2.
Nat Immunol ; 23(10): 1484-1494, 2022 10.
Article in English | MEDLINE | ID: mdl-36138182

ABSTRACT

The heterogeneous cellular microenvironment of human airway chronic inflammatory diseases, including chronic rhinosinusitis (CRS) and asthma, is still poorly understood. Here, we performed single-cell RNA sequencing (scRNA-seq) on the nasal mucosa of healthy individuals and patients with three subtypes of CRS and identified disease-specific cell subsets and molecules that specifically contribute to the pathogenesis of CRS subtypes. As such, ALOX15+ macrophages contributed to the type 2 immunity-driven pathogenesis of one subtype of CRS, eosinophilic CRS with nasal polyps (eCRSwNP), by secreting chemokines that recruited eosinophils, monocytes and T helper 2 (TH2) cells. An inhibitor of ALOX15 reduced the release of proinflammatory chemokines in human macrophages and inhibited the overactivation of type 2 immunity in a mouse model of eosinophilic rhinosinusitis. Our findings advance the understanding of the heterogeneous immune microenvironment and the pathogenesis of CRS subtypes and identify potential therapeutic approaches for the treatment of CRS and potentially other type 2 immunity-mediated diseases.


Subject(s)
Nasal Polyps , Rhinitis , Sinusitis , Animals , Chronic Disease , Eosinophils , Humans , Mice , Nasal Mucosa
3.
Nature ; 617(7962): 717-723, 2023 05.
Article in English | MEDLINE | ID: mdl-37225883

ABSTRACT

Flexible solar cells have a lot of market potential for application in photovoltaics integrated into buildings and wearable electronics because they are lightweight, shockproof and self-powered. Silicon solar cells have been successfully used in large power plants. However, despite the efforts made for more than 50 years, there has been no notable progress in the development of flexible silicon solar cells because of their rigidity1-4. Here we provide a strategy for fabricating large-scale, foldable silicon wafers and manufacturing flexible solar cells. A textured crystalline silicon wafer always starts to crack at the sharp channels between surface pyramids in the marginal region of the wafer. This fact enabled us to improve the flexibility of silicon wafers by blunting the pyramidal structure in the marginal regions. This edge-blunting technique enables commercial production of large-scale (>240 cm2), high-efficiency (>24%) silicon solar cells that can be rolled similarly to a sheet of paper. The cells retain 100% of their power conversion efficiency after 1,000 side-to-side bending cycles. After being assembled into large (>10,000 cm2) flexible modules, these cells retain 99.62% of their power after thermal cycling between -70 °C and 85 °C for 120 h. Furthermore, they retain 96.03% of their power after 20 min of exposure to air flow when attached to a soft gasbag, which models wind blowing during a violent storm.

4.
Mol Cell ; 78(1): 168-183.e5, 2020 04 02.
Article in English | MEDLINE | ID: mdl-32130890

ABSTRACT

Crossover recombination is essential for accurate chromosome segregation during meiosis. The MutSγ complex, Msh4-Msh5, facilitates crossing over by binding and stabilizing nascent recombination intermediates. We show that these activities are governed by regulated proteolysis. MutSγ is initially inactive for crossing over due to an N-terminal degron on Msh4 that renders it unstable by directly targeting proteasomal degradation. Activation of MutSγ requires the Dbf4-dependent kinase Cdc7 (DDK), which directly phosphorylates and thereby neutralizes the Msh4 degron. Genetic requirements for Msh4 phosphorylation indicate that DDK targets MutSγ only after it has bound to nascent joint molecules (JMs) in the context of synapsing chromosomes. Overexpression studies confirm that the steady-state level of Msh4, not phosphorylation per se, is the critical determinant for crossing over. At the DNA level, Msh4 phosphorylation enables the formation and crossover-biased resolution of double-Holliday Junction intermediates. Our study establishes regulated protein degradation as a fundamental mechanism underlying meiotic crossing over.


Subject(s)
Crossing Over, Genetic , DNA-Binding Proteins/metabolism , Meiosis/genetics , Proteasome Endopeptidase Complex/metabolism , Saccharomyces cerevisiae Proteins/metabolism , Cell Cycle Proteins/metabolism , Chromosome Pairing , DNA-Binding Proteins/chemistry , Phosphorylation , Protein Serine-Threonine Kinases/metabolism , Proteolysis , Saccharomyces cerevisiae Proteins/chemistry
5.
Proc Natl Acad Sci U S A ; 121(34): e2317944121, 2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39145937

ABSTRACT

Electrical triggering of a metal-insulator transition (MIT) often results in the formation of characteristic spatial patterns such as a metallic filament percolating through an insulating matrix or an insulating barrier splitting a conducting matrix. When MIT triggering is driven by electrothermal effects, the temperature of the filament or barrier can be substantially higher than the rest of the material. Using X-ray microdiffraction and dark-field X-ray microscopy, we show that electrothermal MIT triggering leads to the development of an inhomogeneous strain profile across the switching device, even when the material does not undergo a pronounced, discontinuous structural transition coinciding with the MIT. Diffraction measurements further reveal evidence of unique features associated with MIT triggering including lattice distortions, tilting, and twinning, which indicate structural nonuniformity of both low- and high-resistance regions inside the switching device. Such lattice deformations do not occur under equilibrium, zero-voltage conditions, highlighting the qualitative difference between states achieved through increasing temperature and applying voltage in nonlinear electrothermal materials. Electrically induced strain, lattice distortions, and twinning could have important contributions in the MIT triggering process and drive the material into nonequilibrium states, providing an unconventional pathway to explore the phase space in strongly correlated electronic systems.

6.
Proc Natl Acad Sci U S A ; 121(21): e2317495121, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38753506

ABSTRACT

Myogenic regeneration relies on the proliferation and differentiation of satellite cells. TECRL (trans-2,3-enoyl-CoA reductase like) is an endoplasmic reticulum protein only expressed in cardiac and skeletal muscle. However, its role in myogenesis remains unknown. We show that TECRL expression is increased in response to injury. Satellite cell-specific deletion of TECRL enhances muscle repair by increasing the expression of EGR2 through the activation of the ERK1/2 signaling pathway, which in turn promotes the expression of PAX7. We further show that TECRL deletion led to the upregulation of the histone acetyltransferase general control nonderepressible 5, which enhances the transcription of EGR2 through acetylation. Importantly, we showed that AAV9-mediated TECRL silencing improved muscle repair in mice. These findings shed light on myogenic regeneration and muscle repair.


Subject(s)
Early Growth Response Protein 2 , Muscle Development , Muscle, Skeletal , Regeneration , Animals , Mice , Muscle, Skeletal/metabolism , Early Growth Response Protein 2/metabolism , Early Growth Response Protein 2/genetics , Muscle Development/genetics , Regeneration/genetics , Up-Regulation , Satellite Cells, Skeletal Muscle/metabolism , PAX7 Transcription Factor/metabolism , PAX7 Transcription Factor/genetics , MAP Kinase Signaling System , Mice, Knockout , Cell Differentiation
7.
Am J Hum Genet ; 110(3): 475-486, 2023 03 02.
Article in English | MEDLINE | ID: mdl-36827971

ABSTRACT

Evidence linking coding germline variants in breast cancer (BC)-susceptibility genes other than BRCA1, BRCA2, and CHEK2 with contralateral breast cancer (CBC) risk and breast cancer-specific survival (BCSS) is scarce. The aim of this study was to assess the association of protein-truncating variants (PTVs) and rare missense variants (MSVs) in nine known (ATM, BARD1, BRCA1, BRCA2, CHEK2, PALB2, RAD51C, RAD51D, and TP53) and 25 suspected BC-susceptibility genes with CBC risk and BCSS. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated with Cox regression models. Analyses included 34,401 women of European ancestry diagnosed with BC, including 676 CBCs and 3,449 BC deaths; the median follow-up was 10.9 years. Subtype analyses were based on estrogen receptor (ER) status of the first BC. Combined PTVs and pathogenic/likely pathogenic MSVs in BRCA1, BRCA2, and TP53 and PTVs in CHEK2 and PALB2 were associated with increased CBC risk [HRs (95% CIs): 2.88 (1.70-4.87), 2.31 (1.39-3.85), 8.29 (2.53-27.21), 2.25 (1.55-3.27), and 2.67 (1.33-5.35), respectively]. The strongest evidence of association with BCSS was for PTVs and pathogenic/likely pathogenic MSVs in BRCA2 (ER-positive BC) and TP53 and PTVs in CHEK2 [HRs (95% CIs): 1.53 (1.13-2.07), 2.08 (0.95-4.57), and 1.39 (1.13-1.72), respectively, after adjusting for tumor characteristics and treatment]. HRs were essentially unchanged when censoring for CBC, suggesting that these associations are not completely explained by increased CBC risk, tumor characteristics, or treatment. There was limited evidence of associations of PTVs and/or rare MSVs with CBC risk or BCSS for the 25 suspected BC genes. The CBC findings are relevant to treatment decisions, follow-up, and screening after BC diagnosis.


Subject(s)
Breast Neoplasms , Female , Humans , Breast Neoplasms/genetics , Genes, BRCA2 , Germ-Line Mutation , Germ Cells , Genetic Predisposition to Disease
8.
Mol Biol Evol ; 41(4)2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38507661

ABSTRACT

Recent studies have suggested that dogs were domesticated during the Last Glacial Maximum (LGM) in Siberia, which contrasts with previous proposed domestication centers (e.g. Europe, the Middle East, and East Asia). Ancient DNA provides a powerful resource for the study of mammalian evolution and has been widely used to understand the genetic history of domestic animals. To understand the maternal genetic history of East Asian dogs, we have made a complete mitogenome dataset of 120 East Asian canids from 38 archaeological sites, including 102 newly sequenced from 12.9 to 1 ka BP (1,000 years before present). The majority (112/119, 94.12%) belonged to haplogroup A, and half of these (55/112, 49.11%) belonged to sub-haplogroup A1b. Most existing mitochondrial haplogroups were present in ancient East Asian dogs. However, mitochondrial lineages in ancient northern dogs (northeastern Eurasia and northern East Asia) were deeper and older than those in southern East Asian dogs. Results suggests that East Asian dogs originated from northeastern Eurasian populations after the LGM, dispersing in two possible directions after domestication. Western Eurasian (Europe and the Middle East) dog maternal ancestries genetically influenced East Asian dogs from approximately 4 ka BP, dramatically increasing after 3 ka BP, and afterwards largely replaced most primary maternal lineages in northern East Asia. Additionally, at least three major mitogenome sub-haplogroups of haplogroup A (A1a, A1b, and A3) reveal at least two major dispersal waves onto the Qinghai-Tibet Plateau in ancient times, indicating eastern (A1b and A3) and western (A1a) Eurasian origins.


Subject(s)
Genome, Mitochondrial , Animals , Dogs , Animals, Domestic/genetics , Asia, Eastern , DNA, Mitochondrial/genetics , Genetic Variation , Haplotypes , Mammals/genetics , Phylogeny
9.
Cell ; 140(1): 74-87, 2010 Jan 08.
Article in English | MEDLINE | ID: mdl-20074521

ABSTRACT

We report that eight heterozygous missense mutations in TUBB3, encoding the neuron-specific beta-tubulin isotype III, result in a spectrum of human nervous system disorders that we now call the TUBB3 syndromes. Each mutation causes the ocular motility disorder CFEOM3, whereas some also result in intellectual and behavioral impairments, facial paralysis, and/or later-onset axonal sensorimotor polyneuropathy. Neuroimaging reveals a spectrum of abnormalities including hypoplasia of oculomotor nerves and dysgenesis of the corpus callosum, anterior commissure, and corticospinal tracts. A knock-in disease mouse model reveals axon guidance defects without evidence of cortical cell migration abnormalities. We show that the disease-associated mutations can impair tubulin heterodimer formation in vitro, although folded mutant heterodimers can still polymerize into microtubules. Modeling each mutation in yeast tubulin demonstrates that all alter dynamic instability whereas a subset disrupts the interaction of microtubules with kinesin motors. These findings demonstrate that normal TUBB3 is required for axon guidance and maintenance in mammals.


Subject(s)
Tubulin/metabolism , Amino Acid Sequence , Animals , Axons/metabolism , Brain/embryology , Brain/metabolism , Cell Survival , Child , Developmental Disabilities , Female , Humans , Kinesins/metabolism , Male , Mice , Mice, Inbred C57BL , Microtubules/metabolism , Models, Molecular , Molecular Sequence Data , Mutation, Missense , Protein Transport , Tubulin/chemistry , Tubulin/genetics
11.
Nature ; 572(7767): 106-111, 2019 08.
Article in English | MEDLINE | ID: mdl-31367028

ABSTRACT

There are two general approaches to developing artificial general intelligence (AGI)1: computer-science-oriented and neuroscience-oriented. Because of the fundamental differences in their formulations and coding schemes, these two approaches rely on distinct and incompatible platforms2-8, retarding the development of AGI. A general platform that could support the prevailing computer-science-based artificial neural networks as well as neuroscience-inspired models and algorithms is highly desirable. Here we present the Tianjic chip, which integrates the two approaches to provide a hybrid, synergistic platform. The Tianjic chip adopts a many-core architecture, reconfigurable building blocks and a streamlined dataflow with hybrid coding schemes, and can not only accommodate computer-science-based machine-learning algorithms, but also easily implement brain-inspired circuits and several coding schemes. Using just one chip, we demonstrate the simultaneous processing of versatile algorithms and models in an unmanned bicycle system, realizing real-time object detection, tracking, voice control, obstacle avoidance and balance control. Our study is expected to stimulate AGI development by paving the way to more generalized hardware platforms.

12.
Nucleic Acids Res ; 51(18): 9880-9893, 2023 10 13.
Article in English | MEDLINE | ID: mdl-37615574

ABSTRACT

High-fidelity clustered regularly interspaced palindromic repeats (CRISPR)-associated protein 9 (Cas9) variants have been developed to reduce the off-target effects of CRISPR systems at a cost of efficiency loss. To systematically evaluate the efficiency and off-target tolerance of Cas9 variants in complex with different single guide RNAs (sgRNAs), we applied high-throughput viability screens and a synthetic paired sgRNA-target system to assess thousands of sgRNAs in combination with two high-fidelity Cas9 variants HiFi and LZ3. Comparing these variants against wild-type SpCas9, we found that ∼20% of sgRNAs are associated with a significant loss of efficiency when complexed with either HiFi or LZ3. The loss of efficiency is dependent on the sequence context in the seed region of sgRNAs, as well as at positions 15-18 in the non-seed region that interacts with the REC3 domain of Cas9, suggesting that the variant-specific mutations in the REC3 domain account for the loss of efficiency. We also observed various degrees of sequence-dependent off-target reduction when different sgRNAs are used in combination with the variants. Given these observations, we developed GuideVar, a transfer learning-based computational framework for the prediction of on-target efficiency and off-target effects with high-fidelity variants. GuideVar facilitates the prioritization of sgRNAs in the applications with HiFi and LZ3, as demonstrated by the improvement of signal-to-noise ratios in high-throughput viability screens using these high-fidelity variants.


Subject(s)
CRISPR-Associated Protein 9 , CRISPR-Cas Systems , Gene Editing , Gene Editing/methods , Mutation , RNA, Guide, CRISPR-Cas Systems , CRISPR-Associated Protein 9/genetics
13.
Proc Natl Acad Sci U S A ; 119(14): e2121998119, 2022 04 05.
Article in English | MEDLINE | ID: mdl-35344440

ABSTRACT

SignificanceAgricultural systems are already major forces of ammonia pollution and environmental degradation. How agricultural ammonia emissions affect the spatio-temporal patterns of nitrogen deposition and where to target future mitigation efforts, remains poorly understood. We develop a substantially complete and coherent agricultural ammonia emissions dataset in nearly recent four decades, and evaluate the relative role of reduced nitrogen in total nitrogen deposition in a spatially explicit way. Global reduced nitrogen deposition has grown rapidly, and will occupy a greater dominant position in total nitrogen deposition without future ammonia regulations. Recognition of agricultural ammonia emissions on nitrogen deposition is critical to formulate effective policies to address ammonia related environmental challenges and protect ecosystems from excessive nitrogen inputs.


Subject(s)
Air Pollutants , Ammonia , Agriculture , Air Pollutants/analysis , Ammonia/analysis , Ecosystem , Environmental Monitoring , Environmental Pollution , Nitrogen/analysis
14.
Am J Physiol Cell Physiol ; 327(2): C487-C504, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-39010835

ABSTRACT

Hypoxia is a critical factor contributing to a poor prognosis and challenging glioma therapy. Previous studies have indicated that hypoxia drives M2 polarization of macrophages and promotes cancer progression in various solid tumors. However, the more complex and diverse mechanisms underlying this process remain to be elucidated. Here, we aimed to examine the functions of hypoxia in gliomas and preliminarily investigate the underlying mechanisms of M2 macrophage polarization caused by hypoxia. We found that hypoxia significantly enhances the malignant phenotypes of U87 and U251 cells by regulating glycolysis. In addition, hypoxia mediated accumulation of the glycolysis product [lactic acid (LA)], which is subsequently absorbed by macrophages to induce its M2 polarization, and this process is reverted by both the glycolysis inhibitor and silenced monocarboxylate transporter (MCT-1) in macrophages, indicating that M2 macrophage polarization is associated with the promotion of glycolysis by hypoxia. Interestingly, we also found that hypoxia mediated LA accumulation in glioma cells upon uptake by macrophages upregulates H3K18La expression and promotes tumor necrosis factor superfamily member 9 (TNFSF9) expression in a histone-lactylation-dependent manner based on the results of chromatin immunoprecipitation sequencing (ChIP seq) enrichment analysis. Subsequent in vitro and in vivo experiments further indicated that TNFSF9 facilitated glioma progression. Mechanistically, hypoxia-mediated LA accumulation in glioma cells is taken up by macrophages and then induces its M2 macrophage polarization by regulating TNFSF9 expression via MCT-1/H3K18La signaling, thus facilitating the malignant progression of gliomas.NEW & NOTEWORTHY Our study revealed that hypoxia induces the production of LA accumulation through glycolysis in glioma cells, which is subsequently absorbed by macrophages and leads to its M2 polarization via the MCT-1/H3K18La/TNFSF9 axis, ultimately significantly promoting the malignant progression of glioma cells. These findings are novel and noteworthy as they provide insights into the connection between energy metabolism and epigenetics in gliomas.


Subject(s)
Glioma , Histones , Macrophages , Glioma/pathology , Glioma/metabolism , Glioma/genetics , Humans , Animals , Macrophages/metabolism , Macrophages/pathology , Mice , Histones/metabolism , Cell Line, Tumor , Glycolysis , Disease Progression , Monocarboxylic Acid Transporters/metabolism , Monocarboxylic Acid Transporters/genetics , Brain Neoplasms/pathology , Brain Neoplasms/metabolism , Brain Neoplasms/genetics , Mice, Nude , Cell Hypoxia , Lactic Acid/metabolism , Gene Expression Regulation, Neoplastic , Macrophage Activation
15.
J Biol Chem ; 299(3): 103020, 2023 03.
Article in English | MEDLINE | ID: mdl-36791914

ABSTRACT

Neural stem cells (NSCs) proliferation and differentiation rely on proper expression and posttranslational modification of transcription factors involved in the determination of cell fate. Further characterization is needed to connect modifying enzymes with their transcription factor substrates in the regulation of these processes. Here, we demonstrated that the inhibition of KAT2A, a histone acetyltransferase, leads to a phenotype of small eyes in the developing embryo of zebrafish, which is associated with enhanced proliferation and apoptosis of NSCs in zebrafish eyes. We confirmed that this phenotype is mediated by the elevated level of PAX6 protein. We further verified that KAT2A negatively regulates PAX6 at the protein level in cultured neural stem cells of rat cerebral cortex. We revealed that PAX6 is a novel acetylation substrate of KAT2A and the acetylation of PAX6 promotes its ubiquitination mediated by the E3 ligase RNF8 that facilitated PAX6 degradation. Our study proposes that KAT2A inhibition results in accelerated proliferation, delayed differentiation, or apoptosis, depending on the context of PAX6 dosage. Thus, the KAT2A/PAX6 axis plays an essential role to keep a balance between the self-renewal and differentiation of NSCs.


Subject(s)
Neural Stem Cells , Zebrafish , Animals , Rats , Cell Differentiation/physiology , Cell Proliferation , Histone Acetyltransferases/genetics , Histone Acetyltransferases/metabolism , Neural Stem Cells/metabolism , PAX6 Transcription Factor/genetics , PAX6 Transcription Factor/metabolism , Transcription Factors/metabolism , Zebrafish/metabolism
16.
BMC Genomics ; 25(1): 235, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38438835

ABSTRACT

BACKGROUND: Orchardgrass (Dactylis glomerata L.), a perennial forage, has the advantages of rich leaves, high yield, and good quality and is one of the most significant forage for grassland animal husbandry and ecological management in southwest China. Mitochondrial (mt) genome is one of the major genetic systems in plants. Studying the mt genome of the genus Dactylis could provide more genetic information in addition to the nuclear genome project of the genus. RESULTS: In this study, we sequenced and assembled two mitochondrial genomes of Dactylis species of D. glomerata (597, 281 bp) and D. aschersoniana (613, 769 bp), based on a combination of PacBio and Illumina. The gene content in the mitochondrial genome of D. aschersoniana is almost identical to the mitochondrial genome of D. glomerata, which contains 22-23 protein-coding genes (PCGs), 8 ribosomal RNAs (rRNAs) and 30 transfer RNAs (tRNAs), while D. glomerata lacks the gene encoding the Ribosomal protein (rps1) and D. aschersoniana contains one pseudo gene (atp8). Twenty-three introns were found among eight of the 30 protein-coding genes, and introns of three genes (nad 1, nad2, and nad5) were trans-spliced in Dactylis aschersoniana. Further, our mitochondrial genome characteristics investigation of the genus Dactylis included codon usage, sequences repeats, RNA editing and selective pressure. The results showed that a large number of short repetitive sequences existed in the mitochondrial genome of D. aschersoniana, the size variation of two mitochondrial genomes is due largely to the presence of a large number of short repetitive sequences. We also identified 52-53 large fragments that were transferred from the chloroplast genome to the mitochondrial genome, and found that the similarity was more than 70%. ML and BI methods used in phylogenetic analysis revealed that the evolutionary status of the genus Dactylis. CONCLUSIONS: Thus, this study reveals the significant rearrangements in the mt genomes of Pooideae species. The sequenced Dactylis mt genome can provide more genetic information and improve our evolutionary understanding of the mt genomes of gramineous plants.


Subject(s)
Genome, Mitochondrial , Animals , Genome, Mitochondrial/genetics , Dactylis , Phylogeny , Comparative Genomic Hybridization , RNA, Ribosomal , Genomics
17.
J Am Chem Soc ; 146(8): 5030-5044, 2024 02 28.
Article in English | MEDLINE | ID: mdl-38359354

ABSTRACT

Aggregate is one of the most extensive existing modes of matters in the world. Besides the research objectives of inanimate systems in physical science, the entities in life science can be regarded as living aggregates, which are far from being thoroughly understood despite the great advances in molecular biology. Molecular biology follows the research philosophy of reductionism, which generally reduces the whole into parts to study. Although reductionism benefits the understanding of molecular behaviors, it encounters limitations when extending to the aggregate level. Holism is another epistemology comparable to reductionism, which studies objectives at the aggregate level, emphasizing the interactions and synergetic/antagonistic effects of a group of composed single entities in determining the characteristics of a whole. As a representative of holism, aggregation-induced emission (AIE) materials have made great achievements in the past two decades in both physical and life science. In particular, the unique properties of AIE materials endow them with in situ and real-time visual methods to investigate the inconsistency between microscopic molecules and macroscopic substances, offering researchers excellent toolkits to study living aggregates. The applications of AIE materials in life science are still in their infancy and worth expanding. In this Perspective, we summarize the research progress of AIE materials in unveiling some phenomena and processes of living systems, aiming to provide a general research approach from the viewpoint of holism. At last, insights into what we can do in the near future are also raised and discussed.


Subject(s)
Molecular Biology , Philosophy
18.
Development ; 148(24)2021 12 15.
Article in English | MEDLINE | ID: mdl-34913465

ABSTRACT

Spermatogonial differentiation and meiotic initiation during spermatogenesis are tightly regulated by a number of genes, including those encoding enzymes for miRNA biogenesis. However, whether and how single miRNAs regulate these processes remain unclear. Here, we report that miR-202, a member of the let-7 family, prevents precocious spermatogonial differentiation and meiotic initiation in spermatogenesis by regulating the timely expression of many genes, including those for key regulators such as STRA8 and DMRT6. In miR-202 knockout (KO) mice, the undifferentiated spermatogonial pool is reduced, accompanied by age-dependent decline of fertility. In KO mice, SYCP3, STRA8 and DMRT6 are expressed earlier than in wild-type littermates, and Dmrt6 mRNA is a direct target of miR-202-5p. Moreover, the precocious spermatogonial differentiation and meiotic initiation were also observed in KO spermatogonial stem cells when cultured and induced in vitro, and could be partially rescued by the knockdown of Dmrt6. Therefore, we have not only shown that miR-202 is a regulator of meiotic initiation but also identified a previously unknown module in the underlying regulatory network.


Subject(s)
Adaptor Proteins, Signal Transducing/genetics , MicroRNAs/genetics , Spermatogenesis/genetics , Spermatogonia/growth & development , Testis/growth & development , Adult Germline Stem Cells/cytology , Animals , Cell Cycle Proteins/genetics , Cell Differentiation/genetics , DNA-Binding Proteins/genetics , Fertility/genetics , Gene Expression Regulation, Developmental/genetics , Male , Meiosis/genetics , Mice , Mice, Knockout , Spermatogonia/metabolism , Testis/metabolism , Transcription Factors/genetics
19.
J Neuroinflammation ; 21(1): 207, 2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39164713

ABSTRACT

Despite advances in antimicrobial and anti-inflammatory treatment, inflammation and its consequences remain a major challenge in the field of medicine. Inflammatory reactions can lead to life-threatening conditions such as septic shock, while chronic inflammation has the potential to worsen the condition of body tissues and ultimately lead to significant impairment of their functionality. Although the central nervous system has long been considered immune privileged to peripheral immune responses, recent research has shown that strong immune responses in the periphery also affect the brain, leading to reactive microglia, which belong to the innate immune system and reside in the brain, and neuroinflammation. The inflammatory response is primarily a protective mechanism to defend against pathogens and tissue damage. However, excessive and chronic inflammation can have negative effects on neuronal structure and function. Neuroinflammation underlies the pathogenesis of many neurological and neurodegenerative diseases and can accelerate their progression. Consequently, targeting inflammatory signaling pathways offers potential therapeutic strategies for various neuropathological conditions, particularly Parkinson's and Alzheimer's disease, by curbing inflammation. Here the blood-brain barrier is a major hurdle for potential therapeutic strategies, therefore it would be highly advantageous to foster and utilize brain innate anti-inflammatory mechanisms. The tricarboxylic acid cycle-derived metabolite itaconate is highly upregulated in activated macrophages and has been shown to act as an immunomodulator with anti-inflammatory and antimicrobial functions. Mesaconate, an isomer of itaconate, similarly reduces the inflammatory response in macrophages. Nevertheless, most studies have focused on its esterified forms and its peripheral effects, while its influence on the CNS remained largely unexplored. Therefore, this study investigated the immunomodulatory and therapeutic potential of endogenously synthesized itaconate and its isomer mesaconate in lipopolysaccharide (LPS)-induced neuroinflammatory processes. Our results show that both itaconate and mesaconate reduce LPS-induced neuroinflammation, as evidenced by lower levels of inflammatory mediators, reduced microglial reactivity and a rescue of synaptic plasticity, the cellular correlate of learning and memory processes in the brain. Overall, this study emphasizes that both itaconate and mesaconate have therapeutic potential for neuroinflammatory processes in the brain and are of remarkable importance due to their endogenous origin and production, which usually leads to high tolerance.


Subject(s)
Lipopolysaccharides , Neuroinflammatory Diseases , Succinates , Animals , Succinates/pharmacology , Succinates/therapeutic use , Neuroinflammatory Diseases/drug therapy , Neuroinflammatory Diseases/metabolism , Neuroinflammatory Diseases/pathology , Neuroinflammatory Diseases/chemically induced , Neuroinflammatory Diseases/immunology , Lipopolysaccharides/toxicity , Brain/drug effects , Brain/metabolism , Brain/pathology , Brain/immunology , Mice , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Male , Mice, Inbred C57BL
20.
Mol Carcinog ; 63(2): 209-223, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37818798

ABSTRACT

Cyclin dependent kinase 4 and 6 inhibitors such as abemaciclib are routinely used to treat metastatic estrogen receptor positive (ER+) breast cancer. However, adaptive mechanisms inhibit their effectiveness and allow for disease progression. Using ER+ breast cancer cell models, we show that acquired resistance to abemaciclib is accompanied by increase in metastatic potential. Mass spectrometry-based proteomics from abemaciclib sensitive and resistant cells showed that lysosomal proteins including CTSD (cathepsin D), cathepsin A and CD68 were significantly increased in resistant cells. Combination of abemaciclib and a lysosomal destabilizer, such as hydroxychloroquine (HCQ) or bafilomycin A1, resensitized resistant cells to abemaciclib. Also, combination of abemaciclib and HCQ decreased migration and invasive potential and increased lysosomal membrane permeability in resistant cells. Prosurvival B cell lymphoma 2 (BCL2) protein levels were elevated in resistant cells, and a triple treatment with abemaciclib, HCQ, and BCL2 inhibitor, venetoclax, significantly inhibited cell growth compared to treatment with abemaciclib and HCQ. Furthermore, resistant cells showed increased levels of Transcription Factor EB (TFEB), a master regulator of lysosomal-autophagy genes, and siRNA mediated knockdown of TFEB decreased invasion in resistant cells. TFEB was found to be mutated in a subset of invasive human breast cancer samples, and overall survival analysis in ER+, lymph node-positive breast cancer showed that increased TFEB expression correlated with decreased survival. Collectively, we show that acquired resistance to abemaciclib leads to increased metastatic potential and increased levels of protumorigenic lysosomal proteins. Therefore, the lysosomal pathway could be a therapeutic target in advanced ER+ breast cancer.


Subject(s)
Aminopyridines , Benzimidazoles , Breast Neoplasms , Proteins , Humans , Female , Breast Neoplasms/metabolism , Lysosomes , Proto-Oncogene Proteins c-bcl-2/metabolism
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