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1.
Cell ; 175(1): 133-145.e15, 2018 09 20.
Article in English | MEDLINE | ID: mdl-30220454

ABSTRACT

Nonalcoholic fatty liver disease (NAFLD) progresses to nonalcoholic steatohepatitis (NASH) in response to elevated endoplasmic reticulum (ER) stress. Whereas the onset of simple steatosis requires elevated de novo lipogenesis, progression to NASH is triggered by accumulation of hepatocyte-free cholesterol. We now show that caspase-2, whose expression is ER-stress inducible and elevated in human and mouse NASH, controls the buildup of hepatic-free cholesterol and triglycerides by activating sterol regulatory element-binding proteins (SREBP) in a manner refractory to feedback inhibition. Caspase-2 colocalizes with site 1 protease (S1P) and cleaves it to generate a soluble active fragment that initiates SCAP-independent SREBP1/2 activation in the ER. Caspase-2 ablation or pharmacological inhibition prevents diet-induced steatosis and NASH progression in ER-stress-prone mice. Caspase-2 inhibition offers a specific and effective strategy for preventing or treating stress-driven fatty liver diseases, whereas caspase-2-generated S1P proteolytic fragments, which enter the secretory pathway, are potential NASH biomarkers.


Subject(s)
Caspase 2/physiology , Lipogenesis/physiology , Proprotein Convertases/physiology , Serine Endopeptidases/physiology , Animals , Cholesterol/metabolism , Endoplasmic Reticulum/physiology , Endoplasmic Reticulum Stress/physiology , Fatty Liver/physiopathology , HEK293 Cells , Hepatocytes/metabolism , Humans , Liver/metabolism , Mice , Mice, Inbred C57BL , Proprotein Convertases/metabolism , Serine Endopeptidases/metabolism , Sterol Regulatory Element Binding Protein 1/metabolism , Triglycerides/metabolism
2.
Cell ; 172(4): 731-743.e12, 2018 02 08.
Article in English | MEDLINE | ID: mdl-29425491

ABSTRACT

The noncanonical IKK family member TANK-binding kinase 1 (TBK1) is activated by pro-inflammatory cytokines, but its role in controlling metabolism remains unclear. Here, we report that the kinase uniquely controls energy metabolism. Tbk1 expression is increased in adipocytes of HFD-fed mice. Adipocyte-specific TBK1 knockout (ATKO) attenuates HFD-induced obesity by increasing energy expenditure; further studies show that TBK1 directly inhibits AMPK to repress respiration and increase energy storage. Conversely, activation of AMPK under catabolic conditions can increase TBK1 activity through phosphorylation, mediated by AMPK's downstream target ULK1. Surprisingly, ATKO also exaggerates adipose tissue inflammation and insulin resistance. TBK1 suppresses inflammation by phosphorylating and inducing the degradation of the IKK kinase NIK, thus attenuating NF-κB activity. Moreover, TBK1 mediates the negative impact of AMPK activity on NF-κB activation. These data implicate a unique role for TBK1 in mediating bidirectional crosstalk between energy sensing and inflammatory signaling pathways in both over- and undernutrition.


Subject(s)
Adipocytes/metabolism , Adipose Tissue/metabolism , Energy Metabolism , Protein Serine-Threonine Kinases/metabolism , Signal Transduction , AMP-Activated Protein Kinases/genetics , AMP-Activated Protein Kinases/metabolism , Adipocytes/pathology , Adipose Tissue/pathology , Animals , Autophagy-Related Protein-1 Homolog/genetics , Autophagy-Related Protein-1 Homolog/metabolism , Cell Line, Transformed , Dietary Fats/adverse effects , Dietary Fats/pharmacology , Inflammation/chemically induced , Inflammation/genetics , Inflammation/metabolism , Inflammation/pathology , Mice , Mice, Knockout , NF-kappa B/genetics , NF-kappa B/metabolism , Oxygen Consumption/drug effects , Phosphorylation/drug effects , Phosphorylation/genetics , Protein Serine-Threonine Kinases/genetics , NF-kappaB-Inducing Kinase
3.
Nature ; 631(8022): 777-782, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38987600

ABSTRACT

Most of the state-of-the-art thermoelectric materials are inorganic semiconductors. Owing to the directional covalent bonding, they usually show limited plasticity at room temperature1,2, for example, with a tensile strain of less than five per cent. Here we discover that single-crystalline Mg3Bi2 shows a room-temperature tensile strain of up to 100 per cent when the tension is applied along the (0001) plane (that is, the ab plane). Such a value is at least one order of magnitude higher than that of traditional thermoelectric materials and outperforms many metals that crystallize in a similar structure. Experimentally, slip bands and dislocations are identified in the deformed Mg3Bi2, indicating the gliding of dislocations as the microscopic mechanism of plastic deformation. Analysis of chemical bonding reveals multiple planes with low slipping barrier energy, suggesting the existence of several slip systems in Mg3Bi2. In addition, continuous dynamic bonding during the slipping process prevents the cleavage of the atomic plane, thus sustaining a large plastic deformation. Importantly, the tellurium-doped single-crystalline Mg3Bi2 shows a power factor of about 55 microwatts per centimetre per kelvin squared and a figure of merit of about 0.65 at room temperature along the ab plane, which outperforms the existing ductile thermoelectric materials3,4.


Subject(s)
Crystallization , Tellurium , Temperature , Tellurium/chemistry , Tensile Strength , Magnesium Compounds/chemistry , Magnesium/chemistry , Barium/chemistry
4.
Immunity ; 49(2): 301-311.e5, 2018 08 21.
Article in English | MEDLINE | ID: mdl-30076101

ABSTRACT

An important class of HIV-1 broadly neutralizing antibodies, termed the VRC01 class, targets the conserved CD4-binding site (CD4bs) of the envelope glycoprotein (Env). An engineered Env outer domain (OD) eOD-GT8 60-mer nanoparticle has been developed as a priming immunogen for eliciting VRC01-class precursors and is planned for clinical trials. However, a substantial portion of eOD-GT8-elicited antibodies target non-CD4bs epitopes, potentially limiting its efficacy. We introduced N-linked glycans into non-CD4bs surfaces of eOD-GT8 to mask irrelevant epitopes and evaluated these mutants in a mouse model that expressed diverse immunoglobulin heavy chains containing human IGHV1-2∗02, the germline VRC01 VH segment. Compared to the parental eOD-GT8, a mutant with five added glycans stimulated significantly higher proportions of CD4bs-specific serum responses and CD4bs-specific immunoglobulin G+ B cells including VRC01-class precursors. These results demonstrate that glycan masking can limit elicitation of off-target antibodies and focus immune responses to the CD4bs, a major target of HIV-1 vaccine design.


Subject(s)
Antibodies, Neutralizing/immunology , Binding Sites, Antibody/immunology , CD4 Antigens/immunology , HIV Antibodies/immunology , HIV-1/immunology , AIDS Vaccines/immunology , Animals , Antibodies, Monoclonal/immunology , Broadly Neutralizing Antibodies , Cell Line , Female , Gene Knock-In Techniques , HIV Envelope Protein gp120/immunology , HIV Infections/immunology , HIV Infections/prevention & control , Humans , Immunoglobulin Heavy Chains/immunology , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Polysaccharides/chemistry
5.
Nature ; 592(7854): 433-437, 2021 04.
Article in English | MEDLINE | ID: mdl-33790463

ABSTRACT

Upon gamete fusion, animal egg cells secrete proteases from cortical granules to establish a fertilization envelope as a block to polyspermy1-4. Fertilization in flowering plants is more complex and involves the delivery of two non-motile sperm cells by pollen tubes5,6. Simultaneous penetration of ovules by multiple pollen tubes (polytubey) is usually avoided, thus indirectly preventing polyspermy7,8. How plant egg cells regulate the rejection of extra tubes after successful fertilization is not known. Here we report that the aspartic endopeptidases ECS1 and ECS2 are secreted to the extracellular space from a cortical network located at the apical domain of the Arabidopsis egg cell. This reaction is triggered only after successful fertilization. ECS1 and ECS2 are exclusively expressed in the egg cell and transcripts are degraded immediately after gamete fusion. ECS1 and ESC2 specifically cleave the pollen tube attractor LURE1. As a consequence, polytubey is frequent in ecs1 ecs2 double mutants. Ectopic secretion of these endopeptidases from synergid cells led to a decrease in the levels of LURE1 and reduced the rate of pollen tube attraction. Together, these findings demonstrate that plant egg cells sense successful fertilization and elucidate a mechanism as to how a relatively fast post-fertilization block to polytubey is established by fertilization-induced degradation of attraction factors.


Subject(s)
Arabidopsis/metabolism , Endopeptidases/metabolism , Fertilization , Ovule/metabolism , Pollen Tube/metabolism , Pollen/metabolism , Arabidopsis/cytology , Arabidopsis/enzymology , Arabidopsis Proteins/metabolism , Cell Fusion , Ovule/enzymology , Pollen/enzymology
6.
Genes Dev ; 33(9-10): 536-549, 2019 05 01.
Article in English | MEDLINE | ID: mdl-30842217

ABSTRACT

The exosome functions in the degradation of diverse RNA species, yet how it is negatively regulated remains largely unknown. Here, we show that NRDE2 forms a 1:1 complex with MTR4, a nuclear exosome cofactor critical for exosome recruitment, via a conserved MTR4-interacting domain (MID). Unexpectedly, NRDE2 mainly localizes in nuclear speckles, where it inhibits MTR4 recruitment and RNA degradation, and thereby ensures efficient mRNA nuclear export. Structural and biochemical data revealed that NRDE2 interacts with MTR4's key residues, locks MTR4 in a closed conformation, and inhibits MTR4 interaction with the exosome as well as proteins important for MTR4 recruitment, such as the cap-binding complex (CBC) and ZFC3H1. Functionally, MID deletion results in the loss of self-renewal of mouse embryonic stem cells. Together, our data pinpoint NRDE2 as a nuclear exosome negative regulator that ensures mRNA stability and nuclear export.


Subject(s)
Exosomes/genetics , Exosomes/metabolism , Nuclear Proteins/physiology , RNA Helicases/metabolism , Animals , Cell Nucleus/metabolism , Embryonic Stem Cells , HEK293 Cells , HeLa Cells , Humans , Mice , Nuclear Proteins/genetics , Protein Binding , Protein Domains , Protein Transport/genetics , RNA Stability/genetics
7.
Development ; 150(18)2023 09 15.
Article in English | MEDLINE | ID: mdl-37680190

ABSTRACT

Taste papillae are specialized organs, each of which comprises an epithelial wall hosting taste buds and a core of mesenchymal tissue. In the present study, we report that during early taste papilla development in mouse embryos, bone morphogenetic protein (BMP) signaling mediated by type 1 receptor ALK3 in the tongue mesenchyme is required for epithelial Wnt/ß-catenin activity and taste papilla differentiation. Mesenchyme-specific knockout (cKO) of Alk3 using Wnt1-Cre and Sox10-Cre resulted in an absence of taste papillae at E12.0. Biochemical and cell differentiation analyses demonstrated that mesenchymal ALK3-BMP signaling governed the production of previously unappreciated secretory proteins, i.e. it suppressed those that inhibit and facilitated those that promote taste papilla differentiation. Bulk RNA-sequencing analysis revealed many more differentially expressed genes (DEGs) in the tongue epithelium than in the mesenchyme in Alk3 cKO versus control. Moreover, we detected downregulated epithelial Wnt/ß-catenin signaling and found that taste papilla development in the Alk3 cKO was rescued by the GSK3ß inhibitor LiCl, but not by Wnt3a. Our findings demonstrate for the first time the requirement of tongue mesenchyme in taste papilla cell differentiation.


Subject(s)
Taste Buds , Animals , Mice , beta Catenin , Taste , Tongue , Cell Differentiation/genetics , Mesoderm
8.
Nucleic Acids Res ; 52(D1): D770-D776, 2024 Jan 05.
Article in English | MEDLINE | ID: mdl-37930838

ABSTRACT

Rhinovirus (RV), a prominent causative agent of both upper and lower respiratory diseases, ranks among the most prevalent human respiratory viruses. RV infections are associated with various illnesses, including colds, asthma exacerbations, croup and pneumonia, imposing significant and extended societal burdens. Characterized by a high mutation rate and genomic diversity, RV displays a diverse serological landscape, encompassing a total of 174 serotypes identified to date. Understanding RV genetic diversity is crucial for epidemiological surveillance and investigation of respiratory diseases. This study introduces a comprehensive and high-quality RV data resource, designated RVdb (http://rvdb.mgc.ac.cn), covering 26 909 currently identified RV strains, along with RV-related sequences, 3D protein structures and publications. Furthermore, this resource features a suite of web-based utilities optimized for easy browsing and searching, as well as automatic sequence annotation, multiple sequence alignment (MSA), phylogenetic tree construction, RVdb BLAST and a serotyping pipeline. Equipped with a user-friendly interface and integrated online bioinformatics tools, RVdb provides a convenient and powerful platform on which to analyse the genetic characteristics of RVs. Additionally, RVdb also supports the efforts of virologists and epidemiologists to monitor and trace both existing and emerging RV-related infectious conditions in a public health context.


Subject(s)
Asthma , Enterovirus Infections , Picornaviridae Infections , Rhinovirus , Humans , Genomics , Phylogeny , Picornaviridae Infections/genetics , Rhinovirus/genetics
9.
Nat Mater ; 23(6): 844-853, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38448658

ABSTRACT

Lymph nodes are crucial organs of the adaptive immune system, orchestrating T cell priming, activation and tolerance. T cell activity and function are highly regulated by lymph nodes, which have a unique structure harbouring distinct cells that work together to detect and respond to pathogen-derived antigens. Here we show that implanted patient-derived freeze-dried lymph nodes loaded with chimeric antigen receptor T cells improve delivery to solid tumours and inhibit tumour recurrence after surgery. Chimeric antigen receptor T cells can be effectively loaded into lyophilized lymph nodes, whose unaltered meshwork and cytokine and chemokine contents promote chimeric antigen receptor T cell viability and activation. In mouse models of cell-line-derived human cervical cancer and patient-derived pancreatic cancer, delivery of chimeric antigen receptor T cells targeting mesothelin via the freeze-dried lymph nodes is more effective in preventing tumour recurrence when compared to hydrogels containing T-cell-supporting cytokines. This tissue-mediated cell delivery strategy holds promise for controlled release of various cells and therapeutics with long-term activity and augmented function.


Subject(s)
Freeze Drying , Lymph Nodes , Mesothelin , Receptors, Chimeric Antigen , Animals , Humans , Mice , Receptors, Chimeric Antigen/immunology , Receptors, Chimeric Antigen/metabolism , Lymph Nodes/immunology , T-Lymphocytes/immunology , T-Lymphocytes/cytology , Cell Line, Tumor , Female , GPI-Linked Proteins/immunology , GPI-Linked Proteins/metabolism , Pancreatic Neoplasms/therapy , Pancreatic Neoplasms/immunology , Pancreatic Neoplasms/pathology
10.
Blood ; 141(7): 766-786, 2023 02 16.
Article in English | MEDLINE | ID: mdl-36322939

ABSTRACT

Extramedullary infiltration (EMI) is a concomitant manifestation that may indicate poor outcome of acute myeloid leukemia (AML). The underlying mechanism remains poorly understood and therapeutic options are limited. Here, we employed single-cell RNA sequencing on bone marrow (BM) and EMI samples from a patient with AML presenting pervasive leukemia cutis. A complement C1Q+ macrophage-like leukemia subset, which was enriched within cutis and existed in BM before EMI manifestations, was identified and further verified in multiple patients with AML. Genomic and transcriptional profiling disclosed mutation and gene expression signatures of patients with EMI that expressed high levels of C1Q. RNA sequencing and quantitative proteomic analysis revealed expression dynamics of C1Q from primary to relapse. Univariate and multivariate analysis demonstrated adverse prognosis significance of C1Q expression. Mechanistically, C1Q expression, which was modulated by transcription factor MAF BZIP transcription factor B, endowed leukemia cells with tissue infiltration ability, which could establish prominent cutaneous or gastrointestinal EMI nodules in patient-derived xenograft and cell line-derived xenograft models. Fibroblasts attracted migration of the C1Q+ leukemia cells through C1Q-globular C1Q receptor recognition and subsequent stimulation of transforming growth factor ß1. This cell-to-cell communication also contributed to survival of C1Q+ leukemia cells under chemotherapy stress. Thus, C1Q served as a marker for AML with adverse prognosis, orchestrating cancer infiltration pathways through communicating with fibroblasts and represents a compelling therapeutic target for EMI.


Subject(s)
Complement C1q , Leukemia, Myeloid, Acute , Humans , Proteomics , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/metabolism , Bone Marrow/metabolism , Prognosis , Chronic Disease , Recurrence
11.
FASEB J ; 38(2): e23440, 2024 01 31.
Article in English | MEDLINE | ID: mdl-38252072

ABSTRACT

CD155, a member of the immunoglobulin superfamily, is closely related to cell proliferation, adhesion, and migration. CD155 is overexpressed on the surface of cancer cells to promote cell proliferation and is upregulated in damaged tissues as a stress-induced molecule. The process of skeletal muscle regeneration after injury is complex and involves injurious stimulation and subsequent satellite cell proliferation. However, the role of CD155 in this process remains unelucidated. This study aimed to explore the role of CD155 in injured skeletal muscle regeneration and to clarify its effect on satellite cell proliferation and differentiation. Here, quantitative real-time polymerase chain reaction (RT-qPCR) and immunofluorescence results indicated that CD155 expression in satellite cells increased after skeletal muscle injury. CD155 knockout in mice impaired the regeneration of skeletal muscle. A bone marrow transplantation mouse model was constructed and revealed that CD155 on skeletal muscle tissues, not immune cells, affected muscle regeneration. In vitro, CD155 knockdown in myoblasts inhibited their proliferation and differentiation. The transcriptomic analysis also indicated that CD155 absence can impair the biological proliferation and differentiation process of myoblasts. Our research demonstrates that CD155 directly promotes injured muscle regeneration by regulating satellite cell proliferation and differentiation, which may be a potential therapeutic molecule for skeletal muscle injury.


Subject(s)
Muscle, Skeletal , Receptors, Virus , Satellite Cells, Skeletal Muscle , Animals , Mice , Bone Marrow Transplantation , Cell Differentiation , Cell Proliferation , Receptors, Virus/genetics
12.
Nature ; 570(7762): 468-473, 2019 06.
Article in English | MEDLINE | ID: mdl-31142836

ABSTRACT

Broadly neutralizing monoclonal antibodies protect against infection with HIV-1 in animal models, suggesting that a vaccine that elicits these antibodies would be protective in humans. However, it has not yet been possible to induce adequate serological responses by vaccination. Here, to activate B cells that express precursors of broadly neutralizing antibodies within polyclonal repertoires, we developed an immunogen, RC1, that facilitates the recognition of the variable loop 3 (V3)-glycan patch on the envelope protein of HIV-1. RC1 conceals non-conserved immunodominant regions by the addition of glycans and/or multimerization on virus-like particles. Immunization of mice, rabbits and rhesus macaques with RC1 elicited serological responses that targeted the V3-glycan patch. Antibody cloning and cryo-electron microscopy structures of antibody-envelope complexes confirmed that immunization with RC1 expands clones of B cells that carry the anti-V3-glycan patch antibodies, which resemble precursors of human broadly neutralizing antibodies. Thus, RC1 may be a suitable priming immunogen for sequential vaccination strategies in the context of polyclonal repertoires.


Subject(s)
AIDS Vaccines/immunology , B-Lymphocytes/immunology , Clone Cells/immunology , HIV-1/chemistry , HIV-1/immunology , Macaca mulatta/immunology , Vaccination , Amino Acid Sequence , Animals , Antibodies, Neutralizing/chemistry , Antibodies, Neutralizing/genetics , Antibodies, Neutralizing/immunology , Antibodies, Neutralizing/ultrastructure , Antibody Affinity , Antibody Specificity/immunology , Antigen-Antibody Complex/immunology , B-Lymphocytes/cytology , Cell Proliferation , Clone Cells/cytology , Cloning, Molecular , Cross-Priming/immunology , Cryoelectron Microscopy , Female , HIV Antibodies/chemistry , HIV Antibodies/genetics , HIV Antibodies/immunology , HIV Antibodies/ultrastructure , Immunodominant Epitopes/chemistry , Immunodominant Epitopes/immunology , Immunodominant Epitopes/ultrastructure , Lymphocyte Activation , Male , Mice , Models, Molecular , Polysaccharides/immunology , Rabbits , Somatic Hypermutation, Immunoglobulin
13.
Cell Mol Life Sci ; 81(1): 122, 2024 Mar 08.
Article in English | MEDLINE | ID: mdl-38456997

ABSTRACT

Doxorubicin-induced cardiotoxicity (DIC), which is a cardiovascular complication, has become the foremost determinant of decreased quality of life and mortality among survivors of malignant tumors, in addition to recurrence and metastasis. The limited ability to accurately predict the occurrence and severity of doxorubicin-induced injury has greatly hindered the prevention of DIC, but reducing the dose to mitigate side effects may compromise the effective treatment of primary malignancies. This has posed a longstanding clinical challenge for oncologists and cardiologists. Ferroptosis in cardiomyocytes has been shown to be a pivotal mechanism underlying cardiac dysfunction in DIC. Ferroptosis is influenced by multiple factors. The innate immune response, as exemplified by neutrophil extracellular traps (NETs), may play a significant role in the regulation of ferroptosis. Therefore, the objective of this study was to investigate the involvement of NETs in doxorubicin-induced cardiomyocyte ferroptosis and elucidate their regulatory role. This study confirmed the presence of NETs in DIC in vivo. Furthermore, we demonstrated that depleting neutrophils effectively reduced the occurrence of doxorubicin-induced ferroptosis and myocardial injury in DIC. Additionally, our findings showed the pivotal role of high mobility group box 1 (HMGB1) as a critical molecule implicated in DIC and emphasized its involvement in the modulation of ferroptosis subsequent to NETs inhibition. Mechanistically, we obtained preliminary evidence suggesting that doxorubicin-induced NETs could modulate yes-associated protein (YAP) activity by releasing HMGB1, which subsequently bound to toll like receptor 4 (TLR4) on the cardiomyocyte membrane, thereby influencing cardiomyocyte ferroptosis in vitro. Our findings suggest that doxorubicin-induced NETs modulate cardiomyocyte ferroptosis via the HMGB1/TLR4/YAP axis, thereby contributing to myocardial injury. This study offers a novel approach for preventing and alleviating DIC by targeting alterations in the immune microenvironment.


Subject(s)
Extracellular Traps , Ferroptosis , HMGB1 Protein , Heart Diseases , Humans , Myocytes, Cardiac/metabolism , Extracellular Traps/metabolism , HMGB1 Protein/metabolism , Toll-Like Receptor 4/metabolism , Cardiotoxicity/metabolism , Quality of Life , Heart Diseases/metabolism , Doxorubicin/adverse effects
14.
Drug Resist Updat ; 76: 101114, 2024 Jun 22.
Article in English | MEDLINE | ID: mdl-38924995

ABSTRACT

Therapy resistance poses a significant obstacle to effective cancer treatment. Recent insights into cell plasticity as a new paradigm for understanding resistance to treatment: as cancer progresses, cancer cells experience phenotypic and molecular alterations, corporately known as cell plasticity. These alterations are caused by microenvironment factors, stochastic genetic and epigenetic changes, and/or selective pressure engendered by treatment, resulting in tumor heterogeneity and therapy resistance. Increasing evidence suggests that cancer cells display remarkable intrinsic plasticity and reversibly adapt to dynamic microenvironment conditions. Dynamic interactions between cell states and with the surrounding microenvironment form a flexible tumor ecosystem, which is able to quickly adapt to external pressure, especially treatment. Here, this review delineates the formation of cancer cell plasticity (CCP) as well as its manipulation of cancer escape from treatment. Furthermore, the intrinsic and extrinsic mechanisms driving CCP that promote the development of therapy resistance is summarized. Novel treatment strategies, e.g., inhibiting or reversing CCP is also proposed. Moreover, the review discusses the multiple lines of ongoing clinical trials globally aimed at ameliorating therapy resistance. Such advances provide directions for the development of new treatment modalities and combination therapies against CCP in the context of therapy resistance.

15.
Proc Natl Acad Sci U S A ; 119(45): e2207608119, 2022 Nov 08.
Article in English | MEDLINE | ID: mdl-36322734

ABSTRACT

Sexual reproduction involves the fusion of two gametes of opposite sex. Although the sperm-expressed fusogen HAPLESS 2 (HAP2) or GENERATIVE CELL SPECIFIC 1 (GCS1) plays a vital role in this process in many eukaryotic organisms and an understanding of its regulation is emerging in unicellular systems [J. Zhang et al., Nat. Commun. 12, 4380 (2021); J. F. Pinello et al. Dev. Cell 56, 3380-3392.e9 (2021)], neither HAP2/GCS1 interactors nor mechanisms for delivery and activation at the fusion site are known in multicellular plants. Here, we show that Arabidopsis thaliana HAP2/GCS1 interacts with two sperm DUF679 membrane proteins (DMP8 and DMP9), which are required for the EGG CELL 1 (EC1)-induced translocation of HAP2/GCS1 from internal storage vesicle to the sperm plasma membrane to ensure successful fertilization. Our studies in Arabidopsis and tobacco provide evidence for a conserved function of DMP8/9-like proteins as HAP2/GCS1 partner in seed plants. Our data suggest that seed plants evolved a DMP8/9-dependent fusogen translocation process to achieve timely acquisition of sperm fusion competence in response to egg cell-derived signals, revealing a previously unknown critical step for successful fertilization.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Carrier Proteins/metabolism , Seeds/metabolism , Arabidopsis/metabolism , Spermatozoa/metabolism , Fertilization/physiology
16.
PLoS Genet ; 18(12): e1010513, 2022 12.
Article in English | MEDLINE | ID: mdl-36477175

ABSTRACT

Walnut (Juglans) species are economically important hardwood trees cultivated worldwide for both edible nuts and high-quality wood. Broad-scale assessments of species diversity, evolutionary history, and domestication are needed to improve walnut breeding. In this study, we sequenced 309 walnut accessions from around the world, including 55 Juglans relatives, 98 wild Persian walnuts (J. regia), 70 J. regia landraces, and 86 J. regia cultivars. The phylogenetic tree indicated that J. regia samples (section Dioscaryon) were monophyletic within Juglans. The core areas of genetic diversity of J. regia germplasm were southwestern China and southern Asia near the Qinghai-Tibet Plateau and the Himalayas, and the uplift of the Himalayas was speculated to be the main factor leading to the current population dynamics of Persian walnut. The pattern of genomic variation in terms of nucleotide diversity, linkage disequilibrium, single nucleotide polymorphisms, and insertions/deletions revealed the domestication and selection footprints in Persian walnut. Selective sweep analysis, GWAS, and expression analysis further identified two transcription factors, JrbHLH and JrMYB6, that influence the thickness of the nut diaphragm as loci under selection during domestication. Our results elucidate the domestication and selection footprints in Persian walnuts and provide a valuable resource for the genomics-assisted breeding of this important crop.


Subject(s)
Juglans , Juglans/genetics , Phylogeny , Asia, Southern , China , Genomics
17.
Nano Lett ; 2024 Jul 22.
Article in English | MEDLINE | ID: mdl-39037901

ABSTRACT

The unique optical properties of graphene, with broadband absorption and ultrafast response, make it a critical component of optoelectronic and spintronic devices. Using time-resolved momentum microscopy with high data rate and high dynamic range, we report momentum-space measurements of electrons promoted to the graphene conduction band with visible light and their subsequent relaxation. We observe a pronounced nonthermal distribution of nascent photoexcited electrons with lattice pseudospin polarization in remarkable agreement with results of simple tight-binding theory. By varying the excitation fluence, we vary the relative importance of electron-electron vs electron-phonon scattering in the relaxation of the initial distribution. Increasing the excitation fluence results in increased noncollinear electron-electron scattering and reduced pseudospin polarization, although up-scattered electrons retain a degree of polarization. These detailed momentum-resolved electron dynamics in graphene demonstrate the capabilities of high-performance time-resolved momentum microscopy in the study of 2D materials and can inform the design of graphene devices.

18.
Plant J ; 116(5): 1385-1400, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37713270

ABSTRACT

Bread wheat, one of the keystone crops for global food security, is challenged by climate change and resource shortage. The root system plays a vital role in water and nutrient absorption, making it essential for meeting the growing global demand. Here, using an association-mapping population composed of 406 accessions, we identified QTrl.Rs-5B modulating seminal root development with a genome-wide association study and validated its genetic effects with two F5 segregation populations. Transcriptome-wide association study prioritized TaFMO1-5B, a gene encoding the flavin-containing monooxygenases, as the causal gene for QTrl.Rs-5B, whose expression levels correlate negatively with the phenotyping variations among our population. The lines silenced for TaFMO1-5B consistently showed significantly larger seminal roots in different genetic backgrounds. Additionally, the agriculture traits measured in multiple environments showed that QTrl.Rs-5B also affects yield component traits and plant architecture-related traits, and its favorable haplotype modulates these traits toward that of modern cultivars, suggesting the application potential of QTrl.Rs-5B for wheat breeding. Consistently, the frequency of the favorable haplotype of QTrl.Rs-5B increased with habitat expansion and breeding improvement of bread wheat. In conclusion, our findings identified and demonstrated the effects of QTrl.Rs-5B on seminal root development and illustrated that it is a valuable genetic locus for wheat root improvement.


Subject(s)
Genome-Wide Association Study , Quantitative Trait Loci , Quantitative Trait Loci/genetics , Triticum/genetics , Transcriptome/genetics , Bread , Plant Breeding , Phenotype , Gene Expression Profiling , Polymorphism, Single Nucleotide/genetics
19.
Glycobiology ; 34(4)2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38263491

ABSTRACT

Modern glycoproteomics experiments require the use of search engines due to the generation of countless spectra. While these tools are valuable, manual validation of search engine results is often required for detailed analysis of glycopeptides as false-discovery rates are often not reliable for glycopeptide data. Near-isobaric mismatches are a common source of misidentifications for the popular glycopeptide-focused search engine pGlyco3.0, and in this technical note we share a strategy and script that improves the accuracy of the search utilizing two manually validated datasets of the glycoproteins CD16a and HIV-1 Env as proof-of-principle.


Subject(s)
Proteomics , Tandem Mass Spectrometry , Glycosylation , Proteomics/methods , Search Engine , Glycopeptides
20.
BMC Genomics ; 25(1): 61, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-38225545

ABSTRACT

BACKGROUND: Sweetpotato is a typical ''potassium (K+) favoring'' food crop, which root differentiation process needs a large supply of potassium fertilizer and determine the final root yield. To further understand the regulatory network of the response to low potassium stress, here we analyze physiological and biochemical characteristics, and investigated root transcriptional changes in two sweetpotato genotypes, namely, - K tolerant "Xu32" and - K susceptible"NZ1". RESULT: We found Xu32 had the higher capability of K+ absorption than NZ1 with better growth performance, higher net photosynthetic rate and higher chlorophyll contents under low potassium stress, and identified 889 differentially expressed genes (DEGs) in Xu32, 634 DEGs in NZ1, 256 common DEGs in both Xu32 and NZ1. The Gene Ontology (GO) term in molecular function enrichment analysis revealed that the DEGs under low K+ stress are predominately involved in catalytic activity, binding, transporter activity and antioxidant activity. Moreover, the more numbers of identified DEGs in Xu32 than that in NZ1 responded to K+-deficiency belong to the process of photosynthesis, carbohydrate metabolism, ion transport, hormone signaling, stress-related and antioxidant system may result in different ability to K+-deficiency tolerance. The unique genes in Xu32 may make a great contribution to enhance low K+ tolerance, and provide useful information for the molecular regulation mechanism of K+-deficiency tolerance in sweetpotato. CONCLUSIONS: The common and distinct expression pattern between the two sweetpotato genotypes illuminate a complex mechanism response to low potassium exist in sweetpotato. The study provides some candidate genes, which can be used in sweetpotato breeding program for improving low potassium stress tolerance.


Subject(s)
Gene Expression Profiling , Gene Expression Regulation, Plant , Genotype , Potassium/metabolism , Photosynthesis/genetics , Transcriptome , Stress, Physiological/genetics
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