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1.
Cell ; 176(5): 998-1013.e16, 2019 02 21.
Article in English | MEDLINE | ID: mdl-30712876

ABSTRACT

Lung cancer is closely associated with chronic inflammation, but the causes of inflammation and the specific immune mediators have not been fully elucidated. The lung is a mucosal tissue colonized by a diverse bacterial community, and pulmonary infections commonly present in lung cancer patients are linked to clinical outcomes. Here, we provide evidence that local microbiota provoke inflammation associated with lung adenocarcinoma by activating lung-resident γδ T cells. Germ-free or antibiotic-treated mice were significantly protected from lung cancer development induced by Kras mutation and p53 loss. Mechanistically, commensal bacteria stimulated Myd88-dependent IL-1ß and IL-23 production from myeloid cells, inducing proliferation and activation of Vγ6+Vδ1+ γδ T cells that produced IL-17 and other effector molecules to promote inflammation and tumor cell proliferation. Our findings clearly link local microbiota-immune crosstalk to lung tumor development and thereby define key cellular and molecular mediators that may serve as effective targets in lung cancer intervention.


Subject(s)
Host Microbial Interactions/immunology , Intraepithelial Lymphocytes/immunology , Lung Neoplasms/immunology , Animals , Cell Proliferation , Female , Interleukin-17/immunology , Interleukin-1beta/metabolism , Interleukin-23/metabolism , Intraepithelial Lymphocytes/metabolism , Intraepithelial Lymphocytes/physiology , Lung/immunology , Lung Neoplasms/metabolism , Male , Mice , Mice, Inbred C57BL , Microbiota/immunology , Myeloid Differentiation Factor 88/metabolism , Neutrophils/immunology , Receptors, Antigen, T-Cell, gamma-delta , Symbiosis/immunology , T-Lymphocytes/immunology
2.
Nature ; 629(8014): 1091-1099, 2024 May.
Article in English | MEDLINE | ID: mdl-38750363

ABSTRACT

The baobab trees (genus Adansonia) have attracted tremendous attention because of their striking shape and distinctive relationships with fauna1. These spectacular trees have also influenced human culture, inspiring innumerable arts, folklore and traditions. Here we sequenced genomes of all eight extant baobab species and argue that Madagascar should be considered the centre of origin for the extant lineages, a key issue in their evolutionary history2,3. Integrated genomic and ecological analyses revealed the reticulate evolution of baobabs, which eventually led to the species diversity seen today. Past population dynamics of Malagasy baobabs may have been influenced by both interspecific competition and the geological history of the island, especially changes in local sea levels. We propose that further attention should be paid to the conservation status of Malagasy baobabs, especially of Adansonia suarezensis and Adansonia grandidieri, and that intensive monitoring of populations of Adansonia za is required, given its propensity for negatively impacting the critically endangered Adansonia perrieri.


Subject(s)
Adansonia , Phylogeny , Adansonia/classification , Adansonia/genetics , Biodiversity , Conservation of Natural Resources , Ecology , Endangered Species , Evolution, Molecular , Genome, Plant/genetics , Madagascar , Population Dynamics , Sea Level Rise
3.
Nature ; 621(7977): 75-81, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37673990

ABSTRACT

Benefiting from high energy density (2,600 Wh kg-1) and low cost, lithium-sulfur (Li-S) batteries are considered promising candidates for advanced energy-storage systems1-4. Despite tremendous efforts in suppressing the long-standing shuttle effect of lithium polysulfides5-7, understanding of the interfacial reactions of lithium polysulfides at the nanoscale remains elusive. This is mainly because of the limitations of in situ characterization tools in tracing the liquid-solid conversion of unstable lithium polysulfides at high temporal-spatial resolution8-10. There is an urgent need to understand the coupled phenomena inside Li-S batteries, specifically, the dynamic distribution, aggregation, deposition and dissolution of lithium polysulfides. Here, by using in situ liquid-cell electrochemical transmission electron microscopy, we directly visualized the transformation of lithium polysulfides over electrode surfaces at the atomic scale. Notably, an unexpected gathering-induced collective charge transfer of lithium polysulfides was captured on the nanocluster active-centre-immobilized surface. It further induced an instantaneous deposition of nonequilibrium Li2S nanocrystals from the dense liquid phase of lithium polysulfides. Without mediation of active centres, the reactions followed a classical single-molecule pathway, lithium polysulfides transforming into Li2S2 and Li2S step by step. Molecular dynamics simulations indicated that the long-range electrostatic interaction between active centres and lithium polysulfides promoted the formation of a dense phase consisting of Li+ and Sn2- (2 < n ≤ 6), and the collective charge transfer in the dense phase was further verified by ab initio molecular dynamics simulations. The collective interfacial reaction pathway unveils a new transformation mechanism and deepens the fundamental understanding of Li-S batteries.

4.
Trends Biochem Sci ; 49(6): 475-476, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38538407

ABSTRACT

Lipid nanodiscs are popular mimetics of biological membranes for determining membrane protein structures. However, a recent study revealed that the choice of nanodisc scaffold directly influenced the structure of an ion channel. This finding prompts us to be cautious and calls for improved membrane mimetics for structure determination.


Subject(s)
Membrane Proteins , Nanostructures , Lipid Bilayers/chemistry , Lipids/chemistry , Membrane Proteins/chemistry , Membrane Proteins/metabolism , Nanostructures/chemistry , Protein Conformation
5.
Immunity ; 51(3): 522-534.e7, 2019 09 17.
Article in English | MEDLINE | ID: mdl-31471107

ABSTRACT

Although recent progress provides mechanistic insights into the pathogenesis of pulmonary fibrosis (PF), rare anti-PF therapeutics show definitive promise for treating this disease. Repeated lung epithelial injury results in injury-repairing response and inflammation, which drive the development of PF. Here, we report that chronic lung injury inactivated the ubiquitin-editing enzyme A20, causing progressive accumulation of the transcription factor C/EBPß in alveolar macrophages (AMs) from PF patients and mice, which upregulated a number of immunosuppressive and profibrotic factors promoting PF development. In response to chronic lung injury, elevated glycogen synthase kinase-3ß (GSK-3ß) interacted with and phosphorylated A20 to suppress C/EBPß degradation. Ectopic expression of A20 or pharmacological restoration of A20 activity by disturbing the A20-GSK-3ß interaction accelerated C/EBPß degradation and showed potent therapeutic efficacy against experimental PF. Our study indicates that a regulatory mechanism of the GSK-3ß-A20-C/EBPß axis in AMs may be a potential target for treating PF and fibroproliferative lung diseases.


Subject(s)
CCAAT-Enhancer-Binding Protein-beta/metabolism , Macrophages/metabolism , Pulmonary Fibrosis/metabolism , Transcription Factors/metabolism , Ubiquitin/metabolism , Animals , Cell Line , Glycogen Synthase Kinase 3 beta/metabolism , HEK293 Cells , Humans , Inflammation/metabolism , Mice , Mice, Inbred C57BL , Phosphorylation/physiology , Signal Transduction/physiology , Ubiquitin-Protein Ligases/metabolism , Ubiquitination/physiology , Up-Regulation/physiology
6.
Proc Natl Acad Sci U S A ; 120(18): e2302325120, 2023 05 02.
Article in English | MEDLINE | ID: mdl-37098056

ABSTRACT

Integral membrane protein structure determination traditionally requires extraction from cell membranes using detergents or polymers. Here, we describe the isolation and structure determination of proteins in membrane vesicles derived directly from cells. Structures of the ion channel Slo1 from total cell membranes and from cell plasma membranes were determined at 3.8 Å and 2.7 Å resolution, respectively. The plasma membrane environment stabilizes Slo1, revealing an alteration of global helical packing, polar lipid, and cholesterol interactions that stabilize previously unresolved regions of the channel and an additional ion binding site in the Ca2+ regulatory domain. The two methods presented enable structural analysis of both internal and plasma membrane proteins without disrupting weakly interacting proteins, lipids, and cofactors that are essential to biological function.


Subject(s)
Ion Channels , Membrane Proteins , Membrane Proteins/metabolism , Cell Membrane/metabolism , Ion Channels/metabolism , Binding Sites
7.
Circulation ; 150(13): 981-993, 2024 Sep 24.
Article in English | MEDLINE | ID: mdl-39166327

ABSTRACT

BACKGROUND: Colchicine has been approved to reduce cardiovascular risk in patients with coronary heart disease on the basis of its potential benefits demonstrated in the COLCOT (Colchicine Cardiovascular Outcomes Trial) and LoDoCo2 (Low-Dose Colchicine 2) studies. Nevertheless, there are limited data available about the specific impact of colchicine on coronary plaques. METHODS: This was a prospective, single-center, randomized, double-blind clinical trial. From May 3, 2021, until August 31, 2022, a total of 128 patients with acute coronary syndrome aged 18 to 80 years with lipid-rich plaque (lipid pool arc >90°) detected by optical coherence tomography were included. The subjects were randomly assigned in a 1:1 ratio to receive either colchicine (0.5 mg once daily) or placebo for 12 months. The primary end point was the change in the minimal fibrous cap thickness from baseline to the 12-month follow-up. RESULTS: Among 128 patients, 52 in the colchicine group and 52 in the placebo group completed the study. The mean age of the 128 patients was 58.0±9.8 years, and 25.0% were female. Compared with placebo, colchicine therapy significantly increased the minimal fibrous cap thickness (51.9 [95% CI, 32.8 to 71.0] µm versus 87.2 [95% CI, 69.9 to 104.5] µm; difference, 34.2 [95% CI, 9.7 to 58.6] µm; P=0.006), and reduced average lipid arc (-25.2° [95% CI, -30.6° to -19.9°] versus -35.7° [95% CI, -40.5° to -30.8°]; difference, -10.5° [95% CI, -17.7° to -3.4°]; P=0.004), mean angular extension of macrophages (-8.9° [95% CI, -13.3° to -4.6°] versus -14.0° [95% CI, -18.0° to -10.0°]; difference, -6.0° [95% CI, -11.8° to -0.2°]; P=0.044), high-sensitivity C-reactive protein level (geometric mean ratio, 0.6 [95% CI, 0.4 to 1.0] versus 0.3 [95% CI, 0.2 to 0.5]; difference, 0.5 [95% CI, 0.3 to 1.0]; P=0.046), interleukin-6 level (geometric mean ratio, 0.8 [95% CI, 0.6 to 1.1] versus 0.5 [95% CI, 0.4 to 0.7]; difference, 0.6 [95% CI, 0.4 to 0.9]; P=0.025), and myeloperoxidase level (geometric mean ratio, 1.0 [95% CI, 0.8 to 1.2] versus 0.8 [95% CI, 0.7 to 0.9]; difference, 0.8 [95% CI, 0.6 to 1.0]; P=0.047). CONCLUSIONS: Our findings suggested that colchicine resulted in favorable effects on coronary plaque stabilization at optical coherence tomography in patients with acute coronary syndrome. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04848857.


Subject(s)
Acute Coronary Syndrome , Colchicine , Plaque, Atherosclerotic , Tomography, Optical Coherence , Humans , Colchicine/therapeutic use , Female , Acute Coronary Syndrome/drug therapy , Acute Coronary Syndrome/diagnostic imaging , Middle Aged , Male , Plaque, Atherosclerotic/drug therapy , Plaque, Atherosclerotic/diagnostic imaging , Double-Blind Method , Aged , Prospective Studies , Adult , Treatment Outcome , Coronary Artery Disease/drug therapy , Coronary Artery Disease/diagnostic imaging
8.
J Virol ; 98(3): e0194423, 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38421166

ABSTRACT

Since the first human infection reported in 2013, H7N9 avian influenza virus (AIV) has been regarded as a serious threat to human health. In this study, we sought to identify the virulence determinant of the H7N9 virus in mammalian hosts. By comparing the virulence of the SH/4664 H7N9 virus, a non-virulent H9N2 virus, and various H7N9-H9N2 hybrid viruses in infected mice, we first pinpointed PB2 as the primary viral factor accounting for the difference between H7N9 and H9N2 in mammalian virulence. We further analyzed the in vivo effects of individually mutating H7N9 PB2 residues different from the closely related H9N2 virus and consequently found residue 473, alongside the well-known residue 627, to be critical for the virulence of the H7N9 virus in mice and the activity of its reconstituted viral polymerase in mammalian cells. The importance of PB2-473 was further strengthened by studying reverse H7N9 substitutions in the H9N2 background. Finally, we surprisingly found that species-specific usage of ANP32A, a family member of host factors connecting with the PB2-627 polymorphism, mediates the contribution of PB2 473 residue to the mammalian adaption of AIV polymerase, as the attenuating effect of PB2 M473T on the viral polymerase activity and viral growth of the H7N9 virus could be efficiently complemented by co-expression of chicken ANP32A but not mouse ANP32A and ANP32B. Together, our studies uncovered the PB2 473 residue as a novel viral host range determinant of AIVs via species-specific co-opting of the ANP32 host factor to support viral polymerase activity.IMPORTANCEThe H7N9 avian influenza virus has been considered to have the potential to cause the next pandemic since the first case of human infection reported in 2013. In this study, we identified PB2 residue 473 as a new determinant of mouse virulence and mammalian adaptation of the viral polymerase of the H7N9 virus and its non-pathogenic H9N2 counterparts. We further demonstrated that the variation in PB2-473 is functionally linked to differential co-opting of the host ANP32A protein in supporting viral polymerase activity, which is analogous to the well-known PB2-627 polymorphism, albeit the two PB2 positions are spatially distant. By providing new mechanistic insight into the PB2-mediated host range determination of influenza A viruses, our study implicated the potential existence of multiple PB2-ANP32 interfaces that could be targets for developing new antivirals against the H7N9 virus as well as other mammalian-adapted influenza viruses.


Subject(s)
Influenza A Virus, H7N9 Subtype , Influenza, Human , Nuclear Proteins , RNA-Binding Proteins , Animals , Humans , Mice , Influenza A Virus, H7N9 Subtype/metabolism , Influenza A Virus, H7N9 Subtype/pathogenicity , Influenza A Virus, H9N2 Subtype , Influenza, Human/virology , Mammals , Nuclear Proteins/metabolism , Nucleotidyltransferases/metabolism , RNA-Binding Proteins/metabolism , RNA-Dependent RNA Polymerase/genetics , RNA-Dependent RNA Polymerase/metabolism , Virulence , Virus Replication
9.
Arterioscler Thromb Vasc Biol ; 44(7): 1617-1627, 2024 07.
Article in English | MEDLINE | ID: mdl-38721707

ABSTRACT

BACKGROUND: While it has been hypothesized that high plaque stress and strain may be related to plaque rupture, its direct verification using in vivo coronary plaque rupture data and full 3-dimensional fluid-structure interaction models is lacking in the current literature due to difficulty in obtaining in vivo plaque rupture imaging data from patients with acute coronary syndrome. This case-control study aims to use high-resolution optical coherence tomography-verified in vivo plaque rupture data and 3-dimensional fluid-structure interaction models to seek direct evidence for the high plaque stress/strain hypothesis. METHODS: In vivo coronary plaque optical coherence tomography data (5 ruptured plaques, 5 no-rupture plaques) were acquired from patients using a protocol approved by the local institutional review board with informed consent obtained. The ruptured caps were reconstructed to their prerupture morphology using neighboring plaque cap and vessel geometries. Optical coherence tomography-based 3-dimensional fluid-structure interaction models were constructed to obtain plaque stress, strain, and flow shear stress data for comparative analysis. The rank-sum test in the nonparametric test was used for statistical analysis. RESULTS: Our results showed that the average maximum cap stress and strain values of ruptured plaques were 142% (457.70 versus 189.22 kPa; P=0.0278) and 48% (0.2267 versus 0.1527 kPa; P=0.0476) higher than that for no-rupture plaques, respectively. The mean values of maximum flow shear stresses for ruptured and no-rupture plaques were 145.02 dyn/cm2 and 81.92 dyn/cm2 (P=0.1111), respectively. However, the flow shear stress difference was not statistically significant. CONCLUSIONS: This preliminary case-control study showed that the ruptured plaque group had higher mean maximum stress and strain values. Due to our small study size, larger scale studies are needed to further validate our findings.


Subject(s)
Coronary Artery Disease , Coronary Vessels , Plaque, Atherosclerotic , Stress, Mechanical , Tomography, Optical Coherence , Humans , Coronary Vessels/diagnostic imaging , Coronary Vessels/physiopathology , Coronary Vessels/pathology , Rupture, Spontaneous , Case-Control Studies , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/physiopathology , Male , Female , Middle Aged , Models, Cardiovascular , Aged , Predictive Value of Tests , Acute Coronary Syndrome/diagnostic imaging , Acute Coronary Syndrome/physiopathology , Acute Coronary Syndrome/etiology
10.
J Immunol ; 211(9): 1367-1375, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37695685

ABSTRACT

A better understanding of the regulatory mechanisms governing the development of memory CD8+ T cells could provide instructive insights into vaccination strategies and T cell-based immunotherapies. In this article, we showed that CD160 surface protein is required for CD8+ T cell memory formation. In the response to acute lymphocytic choriomeningitis virus infection in a mouse model, CD160 ablation resulted in the failure of the development of all three memory CD8+ T cell subsets (central, effective, and tissue-resident memory), concomitant with a skewed differentiation into short-lived effector T cells. Such memory-related defect was manifested by a diminished protection from viral rechallenge. Mechanistically, CD160 deficiency led to downregulation of 4-1BB in activated CD8+ T cells, which contributes to the impaired cell survival and decreased respiratory capacity. The nexus between CD160 and 4-1BB was substantiated by the observation that ectopic introduction of 4-1BB was able to largely complement the loss of CD160 in memory CD8+ T cell development. Collectively, our studies discovered that CD160, once thought to be a coinhibitor of T cell signaling, is an essential promoter of memory CD8+ T cell development via activation of the costimulatory molecule 4-1BB.

11.
Proc Natl Acad Sci U S A ; 119(27): e2115939119, 2022 Jul 05.
Article in English | MEDLINE | ID: mdl-35763578

ABSTRACT

Positive magnetoresistance (PMR) and negative magnetoresistance (NMR) describe two opposite responses of resistance induced by a magnetic field. Materials with giant PMR are usually distinct from those with giant NMR due to different physical natures. Here, we report the unusual photomagnetoresistance in the van der Waals heterojunctions of WSe2/quasi-two-dimensional electron gas, showing the coexistence of giant PMR and giant NMR. The PMR and NMR reach 1,007.5% at -9 T and -93.5% at 2.2 T in a single device, respectively. The magnetoresistance spans over two orders of magnitude on inversion of field direction, implying a giant unidirectional magnetoresistance (UMR). By adjusting the thickness of the WSe2 layer, we achieve the maxima of PMR and NMR, which are 4,900,000% and -99.8%, respectively. The unique magnetooptical transport shows the unity of giant UMR, PMR, and NMR, referred to as giant bipolar unidirectional photomagnetoresistance. These features originate from strong out-of-plane spin splitting, magnetic field-enhanced recombination of photocarriers, and the Zeeman effect through our experimental and theoretical investigations. This work offers directions for high-performance light-tunable spintronic devices.NMR).

12.
Chem Soc Rev ; 53(10): 5264-5290, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38619389

ABSTRACT

The energy storage and vehicle industries are heavily investing in advancing all-solid-state batteries to overcome critical limitations in existing liquid electrolyte-based lithium-ion batteries, specifically focusing on mitigating fire hazards and improving energy density. All-solid-state lithium-sulfur batteries (ASSLSBs), featuring earth-abundant sulfur cathodes, high-capacity metallic lithium anodes, and non-flammable solid electrolytes, hold significant promise. Despite these appealing advantages, persistent challenges like sluggish sulfur redox kinetics, lithium metal failure, solid electrolyte degradation, and manufacturing complexities hinder their practical use. To facilitate the transition of these technologies to an industrial scale, bridging the gap between fundamental scientific research and applied R&D activities is crucial. Our review will address the inherent challenges in cell chemistries within ASSLSBs, explore advanced characterization techniques, and delve into innovative cell structure designs. Furthermore, we will provide an overview of the recent trends in R&D and investment activities from both academia and industry. Building on the fundamental understandings and significant progress that has been made thus far, our objective is to motivate the battery community to advance ASSLSBs in a practical direction and propel the industrialized process.

13.
Nano Lett ; 2024 Oct 04.
Article in English | MEDLINE | ID: mdl-39364886

ABSTRACT

Multiplexed optical techniques with multichannel patterns provide powerful strategies for high-capacity anti-counterfeiting. However, it is still a big challenge to meet the demands of achieving high encryption levels, excellent readability, and simple preparation simultaneously. Herein, we use a multistep imprinting technique, leveraging surface work-hardening to massively produce multiplexed encrypted patterns with hierarchical structures. These patterns with coupled nano- and microstructures can be instantaneously decoded into different pieces of information at different view angles under white light illumination. By incorporating perpendicular nano- and microgratings, we achieve four-channel encoded patterns, enhancing anti-counterfeiting capacity. This versatile method works on various metal/polymer materials, offering high-density information storage, direct visibility, broad material compatibility, and low-cost mass production. Our high-performance anti-counterfeiting patterns show significant potential in real-world applications.

14.
J Cell Mol Med ; 28(14): e18543, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39054575

ABSTRACT

The significance of iron in myocardial mitochondria function cannot be underestimated, because deviations in iron levels within cardiomyocytes may have profound detrimental effects on cardiac function. In this study, we investigated the effects of ferroportin 1 (FPN1) on cardiac iron levels and pathological alterations in mice subjected to chronic intermittent hypoxia (CIH). The cTNT-FPN1 plasmid was administered via tail vein injection to induce the mouse with FPN1 overexpression in the cardiomyocytes. CIH was established by exposing the mice to cycles of 21%-5% FiO2 for 3 min, 8 h per day. Subsequently, the introduction of hepcidin resulted in a reduction in FPN1 expression, and H9C2 cells were used to establish an IH model to further elucidate the role of FPN1. First, FPN1 overexpression ameliorated CIH-induced cardiac dysfunction, myocardial hypertrophy, mitochondrial damage and apoptosis. Second, FPN1 overexpression attenuated ROS levels during CIH. In addition, FPN1 overexpression mitigated CIH-induced cardiac iron accumulation. Moreover, the administration of hepcidin resulted in a reduction in FPN1 levels, further accelerating the CIH-induced levels of ROS, LIP and apoptosis in H9C2 cells. These findings indicate that the overexpression of FPN1 in cardiomyocytes inhibits CIH-induced cardiac iron accumulation, subsequently reducing ROS levels and mitigating mitochondrial damage. Conversely, the administration of hepcidin suppressed FPN1 expression and worsened cardiomyocyte iron toxicity injury.


Subject(s)
Apoptosis , Cardiomegaly , Cation Transport Proteins , Hypoxia , Iron , Myocytes, Cardiac , Reactive Oxygen Species , Animals , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology , Cardiomegaly/metabolism , Cardiomegaly/genetics , Cardiomegaly/pathology , Cardiomegaly/etiology , Cation Transport Proteins/metabolism , Cation Transport Proteins/genetics , Hypoxia/metabolism , Hypoxia/complications , Mice , Reactive Oxygen Species/metabolism , Iron/metabolism , Male , Hepcidins/metabolism , Hepcidins/genetics , Cell Line , Mice, Inbred C57BL , Disease Models, Animal , Rats
15.
J Biol Chem ; 299(6): 104689, 2023 06.
Article in English | MEDLINE | ID: mdl-37044216

ABSTRACT

The basal chordate amphioxus is a model for tracing the origin and evolution of vertebrate immunity. To explore the evolution of immunoreceptor signaling pathways, we searched the associated receptors of the amphioxus Branchiostoma belcheri (Bb) homolog of immunoreceptor signaling adaptor protein Grb2. Mass-spectrum analysis of BbGrb2 immunoprecipitates from B. belcheri intestine lysates revealed a folate receptor (FR) domain- and leucine-rich repeat (LRR)-containing protein (FrLRR). Sequence and structural analysis showed that FrLRR is a membrane protein with a predicted curved solenoid structure. The N-terminal Fr domain contains very few folate-binding sites; the following LRR region is a Slit2-type LRR, and a GPI-anchored site was predicted at the C-terminus. RT-PCR analysis showed FrLRR is a transcription-mediated fusion gene of BbFR-like and BbSlit2-N-like genes. Genomic DNA structure analysis implied the B. belcheri FrLRR gene locus and the corresponding locus in Branchiostoma floridae might be generated by exon shuffling of a Slit2-N-like gene into an FR gene. RT-qPCR, immunostaining, and immunoblot results showed that FrLRR was primarily distributed in B. belcheri intestinal tissue. We further demonstrated that FrLRR localized to the cell membrane and lysosomes. Functionally, FrLRR mediated and promoted bacteria-binding and phagocytosis, and FrLRR antibody blocking or Grb2 knockdown inhibited FrLRR-mediated phagocytosis. Interestingly, we found that human Slit2-N (hSlit2-N) also mediated direct bacteria-binding and phagocytosis which was inhibited by Slit2-N antibody blocking or Grb2 knockdown. Together, these results indicate FrLRR and hSlit2-N may function as phagocytotic-receptors to promote phagocytosis through Grb2, implying the Slit2-N-type-LRR-containing proteins play a role in bacterial binding and elimination.


Subject(s)
Lancelets , Animals , Humans , Lancelets/genetics , Leucine , Binding Sites , Signal Transduction , Phagocytosis , Phylogeny
16.
J Am Chem Soc ; 146(28): 18899-18904, 2024 Jul 17.
Article in English | MEDLINE | ID: mdl-38975975

ABSTRACT

In recent years, dysprosium macrocycle single-molecule magnets (SMMs) have received increasing attention due to their excellent air/thermal stability, strong magnetic anisotropy, and rigid molecular skeleton. However, they usually display fast zero-field quantum tunneling of the magnetization (QTM) rate, severely hindering their data storage applications. Herein, we report the design, synthesis, and characterization of an air-stable monodecker didysprosium macrocycle integrating strong single-ion anisotropy, near-perfect local crystal field (CF) symmetry, and efficient exchange bias. These indispensable features enable clear-cut elucidation of the crucial role of very weak antiferromagnetic coupling on magnetization dynamics, creating a prominent SMM with a large effective energy barrier (Ueff) of 670 cm-1, open hysteresis loops at zero field up to 14.9 K, and a record relaxation time of QTM (τQTM), 24281 s, for all known nonradical-bridged lanthanide SMMs.

17.
J Am Chem Soc ; 146(20): 14058-14066, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38733559

ABSTRACT

Metal-organic framework (MOF) membranes with high ion selectivity are highly desirable for direct lithium-ion (Li+) separation from industrial brines. However, very few MOF membranes can efficiently separate Li+ from brines of high Mg2+/Li+ concentration ratios and keep stable in ultrahigh Mg2+-concentrated brines. This work reports a type of MOF-channel membranes (MOFCMs) by growing UiO-66-(SH)2 into the nanochannels of polymer substrates to improve the efficiency of MOF membranes for challenging Li+ extraction. The resulting membranes demonstrate excellent monovalent metal ion selectivity over divalent metal ions, with Li+/Mg2+ selectivity up to 103 since Mg2+ should overcome a higher energy barrier than Li+ when transported through the MOF pores, as confirmed by molecular dynamics simulations. Under dual-ion diffusion, as the Mg2+/Li+ mole ratio of the feed solution increases from 0.2 to 30, the membrane Li+/Mg2+ selectivity decreases from 1516 to 19, corresponding to the purity of lithium products between 99.9 and 95.0%. Further research on multi-ion diffusion that involves Mg2+ and three monovalent metal ions (K+, Na+, and Li+, referred to as M+) in the feed solutions shows a significant improvement in Li+/Mg2+ separation efficiency. The Li+/Mg2+ selectivity can go up to 1114 when the Mg2+/M+ molar concentration ratio is 1:1, and it remains at 19 when the ratio is 30:1. The membrane selectivity is also stable for 30 days in a highly concentrated solution with a high Mg2+/Li+ concentration ratio. These results indicate the feasibility of the MOFCMs for direct lithium extraction from brines with Mg2+ concentrations up to 3.5 M. This study provides an alternative strategy for designing efficient MOF membranes in extracting valuable minerals in the future.

18.
J Am Chem Soc ; 146(33): 23092-23102, 2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39108025

ABSTRACT

Enantiopure Si-stereogenic organosilanes are highly valued in the fields of organic synthesis, development of advanced materials, and drug discovery. However, they are not naturally occurring, and their synthesis has been largely confined to resolution of racemic silanes or desymmetrization of symmetric silanes. In contrast, the dynamic kinetic asymmetric transformation (DYKAT) of racemic organosilanes offers a mechanistically distinct approach and would broaden the accessibility of Si-stereogenic silanes in an enantioconvergent manner. In this study, we report a Lewis base-catalyzed DYKAT of racemic chlorosilanes. The chiral isothiourea catalyst, (S)-benzotetramisole, facilitates silyletherification with phenols, yielding (R)-silylethers in good yields with high enantioselectivity (27 examples, up to 86% yield, up to 98:2 er). Kinetic analysis, control experiments, and DFT calculations suggest that a two-catalyst-bound pentacoordinate silicate is responsible for the Si-configurational epimerization of the ion-paired tetracoordinated silicon intermediates.

19.
J Am Chem Soc ; 2024 Oct 01.
Article in English | MEDLINE | ID: mdl-39354739

ABSTRACT

Li-rich Mn-based cathode materials (LRMO) are promising for enhancing energy density of all-solid-state batteries (ASSBs). Nonetheless, the development of efficient Li+/e- pathways is hindered by the poor electrical conductivity of LRMO cathodes and their incompatible interfaces with solid electrolytes (SEs). Herein, we propose a strategy of in-situ bulk/interfacial structure design to construct fast and stable Li+/e- pathways by introducing Li2WO4, which reduces the energy barrier for Li+ migration and enhances the stability of the surface oxygen structure. The reversibility of oxygen redox was improved, and the voltage decay of the LRMO cathode was addressed significantly. As a result, the bulk structure of the LRMO cathodes and the high-voltage solid-solid interfacial stability are improved. Therefore, the ASSBs achieve a high areal capacity (∼3.15 mAh/cm2) and outstanding cycle stability of ≥1200 cycles with 84.1% capacity retention at 1 C at 25 °C. This study offers new insights into LRMO cathode design strategies for ASSBs, focusing on ultrastable high-voltage interfaces and high-loading composite electrodes.

20.
Hum Mol Genet ; 31(11): 1733-1746, 2022 06 04.
Article in English | MEDLINE | ID: mdl-34888668

ABSTRACT

A highly evolutionarily conserved myeloid ecotropic viral integration site 1 (MEIS1) intronic region is strongly associated with restless legs syndrome (RLS) and insomnia. To understand its regulatory function, we dissected the region by analyzing chromatin accessibility, enhancer-promoter contacts, DNA methylation and expression quantitative trait locus (eQTLs) in different human neural cell types and tissues. We observed specific activity with respect to cell type and developmental maturation, indicating a prominent role for distinct highly conserved intronic elements in forebrain inhibitory neuron differentiation. Two elements were hypomethylated in neural cells with higher MEIS1 expression, suggesting a role of enhancer demethylation in gene regulation. MEIS1 eQTLs showed a striking modular chromosomal distribution, with forebrain eQTLs clustering in intron 8/9. Clustered regularly interspersed short palindromic repeats interference targeting of individual elements in this region attenuated MEIS1 expression, revealing a complex regulatory interplay of distinct elements. In summary, we found that MEIS1 regulation is organized in a modular pattern. Disease-associated intronic regulatory elements control MEIS1 expression with cell type and maturation stage specificity, particularly in the inhibitory neuron lineage. The precise spatiotemporal activity of these elements likely contributes to the pathogenesis of insomnia and RLS.


Subject(s)
Myeloid Ecotropic Viral Integration Site 1 Protein , Restless Legs Syndrome , Sleep Initiation and Maintenance Disorders , Epigenesis, Genetic , Humans , Introns/genetics , Myeloid Ecotropic Viral Integration Site 1 Protein/genetics , Restless Legs Syndrome/genetics , Sleep Initiation and Maintenance Disorders/genetics
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