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1.
Cell ; 186(4): 850-863.e16, 2023 02 16.
Article in English | MEDLINE | ID: mdl-36803605

ABSTRACT

It is unknown whether pangolins, the most trafficked mammals, play a role in the zoonotic transmission of bat coronaviruses. We report the circulation of a novel MERS-like coronavirus in Malayan pangolins, named Manis javanica HKU4-related coronavirus (MjHKU4r-CoV). Among 86 animals, four tested positive by pan-CoV PCR, and seven tested seropositive (11 and 12.8%). Four nearly identical (99.9%) genome sequences were obtained, and one virus was isolated (MjHKU4r-CoV-1). This virus utilizes human dipeptidyl peptidase-4 (hDPP4) as a receptor and host proteases for cell infection, which is enhanced by a furin cleavage site that is absent in all known bat HKU4r-CoVs. The MjHKU4r-CoV-1 spike shows higher binding affinity for hDPP4, and MjHKU4r-CoV-1 has a wider host range than bat HKU4-CoV. MjHKU4r-CoV-1 is infectious and pathogenic in human airways and intestinal organs and in hDPP4-transgenic mice. Our study highlights the importance of pangolins as reservoir hosts of coronaviruses poised for human disease emergence.


Subject(s)
Coronavirus Infections , Coronavirus , Dipeptidyl Peptidase 4 , Pangolins , Animals , Humans , Mice , Chiroptera , Coronavirus Infections/veterinary , Coronavirus Infections/virology , Dipeptidyl Peptidase 4/genetics , Dipeptidyl Peptidase 4/metabolism , Endopeptidases/metabolism , Middle East Respiratory Syndrome Coronavirus/genetics , Middle East Respiratory Syndrome Coronavirus/metabolism , Peptide Hydrolases/metabolism , Receptors, Virus/metabolism , Virus Internalization , Coronavirus/physiology
2.
Cell ; 182(1): 50-58.e8, 2020 07 09.
Article in English | MEDLINE | ID: mdl-32516571

ABSTRACT

COVID-19 has spread worldwide since 2019 and is now a severe threat to public health. We previously identified the causative agent as a novel SARS-related coronavirus (SARS-CoV-2) that uses human angiotensin-converting enzyme 2 (hACE2) as the entry receptor. Here, we successfully developed a SARS-CoV-2 hACE2 transgenic mouse (HFH4-hACE2 in C3B6 mice) infection model. The infected mice generated typical interstitial pneumonia and pathology that were similar to those of COVID-19 patients. Viral quantification revealed the lungs as the major site of infection, although viral RNA could also be found in the eye, heart, and brain in some mice. Virus identical to SARS-CoV-2 in full-genome sequences was isolated from the infected lung and brain tissues. Last, we showed that pre-exposure to SARS-CoV-2 could protect mice from severe pneumonia. Our results show that the hACE2 mouse would be a valuable tool for testing potential vaccines and therapeutics.


Subject(s)
Betacoronavirus/physiology , Coronavirus Infections/pathology , Disease Models, Animal , Mice, Transgenic , Pneumonia, Viral/pathology , Angiotensin-Converting Enzyme 2 , Animals , COVID-19 , Female , Humans , Lung Diseases, Interstitial/pathology , Lung Diseases, Interstitial/virology , Male , Mice , Mice, Inbred C3H , Mice, Inbred C57BL , Mice, Transgenic/genetics , Pandemics , Peptidyl-Dipeptidase A/genetics , SARS-CoV-2 , Viral Tropism , Weight Loss
3.
Cell ; 182(2): 417-428.e13, 2020 07 23.
Article in English | MEDLINE | ID: mdl-32526208

ABSTRACT

Nucleotide analog inhibitors, including broad-spectrum remdesivir and favipiravir, have shown promise in in vitro assays and some clinical studies for COVID-19 treatment, this despite an incomplete mechanistic understanding of the viral RNA-dependent RNA polymerase nsp12 drug interactions. Here, we examine the molecular basis of SARS-CoV-2 RNA replication by determining the cryo-EM structures of the stalled pre- and post- translocated polymerase complexes. Compared with the apo complex, the structures show notable structural rearrangements happening to nsp12 and its co-factors nsp7 and nsp8 to accommodate the nucleic acid, whereas there are highly conserved residues in nsp12, positioning the template and primer for an in-line attack on the incoming nucleotide. Furthermore, we investigate the inhibition mechanism of the triphosphate metabolite of remdesivir through structural and kinetic analyses. A transition model from the nsp7-nsp8 hexadecameric primase complex to the nsp12-nsp7-nsp8 polymerase complex is also proposed to provide clues for the understanding of the coronavirus transcription and replication machinery.


Subject(s)
Betacoronavirus/chemistry , Betacoronavirus/enzymology , RNA-Dependent RNA Polymerase/chemistry , Viral Nonstructural Proteins/chemistry , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/chemistry , Adenosine Monophosphate/metabolism , Adenosine Monophosphate/pharmacology , Alanine/analogs & derivatives , Alanine/chemistry , Alanine/metabolism , Alanine/pharmacology , Antiviral Agents/chemistry , Antiviral Agents/metabolism , Antiviral Agents/pharmacology , Catalytic Domain , Coronavirus RNA-Dependent RNA Polymerase , Cryoelectron Microscopy , Models, Chemical , Models, Molecular , RNA, Viral/metabolism , SARS-CoV-2 , Transcription, Genetic , Virus Replication
4.
Nature ; 632(8024): 267-272, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38987606

ABSTRACT

The fermionic Hubbard model (FHM)1 describes a wide range of physical phenomena resulting from strong electron-electron correlations, including conjectured mechanisms for unconventional superconductivity. Resolving its low-temperature physics is, however, challenging theoretically or numerically. Ultracold fermions in optical lattices2,3 provide a clean and well-controlled platform offering a path to simulate the FHM. Doping the antiferromagnetic ground state of a FHM simulator at half-filling is expected to yield various exotic phases, including stripe order4, pseudogap5, and d-wave superfluid6, offering valuable insights into high-temperature superconductivity7-9. Although the observation of antiferromagnetic correlations over short10 and extended distances11 has been obtained, the antiferromagnetic phase has yet to be realized as it requires sufficiently low temperatures in a large and uniform quantum simulator. Here we report the observation of the antiferromagnetic phase transition in a three-dimensional fermionic Hubbard system comprising lithium-6 atoms in a uniform optical lattice with approximately 800,000 sites. When the interaction strength, temperature and doping concentration are finely tuned to approach their respective critical values, a sharp increase in the spin structure factor is observed. These observations can be well described by a power-law divergence, with a critical exponent of 1.396 from the Heisenberg universality class12. At half-filling and with optimal interaction strength, the measured spin structure factor reaches 123(8), signifying the establishment of an antiferromagnetic phase. Our results provide opportunities for exploring the low-temperature phase diagram of the FHM.

5.
Annu Rev Genet ; 55: 479-496, 2021 11 23.
Article in English | MEDLINE | ID: mdl-34530637

ABSTRACT

High-throughput single-cell transcriptomic approaches have revolutionized our view of gene expression at the level of individual cells, providing new insights into their heterogeneity, identities, and functions. Recently, technical challenges to the application of single-cell transcriptomics to plants have been overcome, and many plant organs and tissues have now been subjected to analyses at single-cell resolution. In this review, we describe these studies and their impact on our understanding of the diversity, differentiation, and activities of plant cells. We particularly highlight their impact on plant cell identity, including unprecedented views of cell transitions and definitions of rare and novel cell types. We also point out current challenges and future opportunities for the application and analyses of single-cell transcriptomics in plants.


Subject(s)
Plant Cells , Transcriptome , Cell Differentiation/genetics , Gene Expression Profiling , Plants/genetics , Single-Cell Analysis , Transcriptome/genetics
6.
Nature ; 622(7982): 376-382, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37696289

ABSTRACT

Nirmatrelvir is a specific antiviral drug that targets the main protease (Mpro) of SARS-CoV-2 and has been approved to treat COVID-191,2. As an RNA virus characterized by high mutation rates, whether SARS-CoV-2 will develop resistance to nirmatrelvir is a question of concern. Our previous studies have shown that several mutational pathways confer resistance to nirmatrelvir, but some result in a loss of viral replicative fitness, which is then compensated for by additional alterations3. The molecular mechanisms for this observed resistance are unknown. Here we combined biochemical and structural methods to demonstrate that alterations at the substrate-binding pocket of Mpro can allow SARS-CoV-2 to develop resistance to nirmatrelvir in two distinct ways. Comprehensive studies of the structures of 14 Mpro mutants in complex with drugs or substrate revealed that alterations at the S1 and S4 subsites substantially decreased the level of inhibitor binding, whereas alterations at the S2 and S4' subsites unexpectedly increased protease activity. Both mechanisms contributed to nirmatrelvir resistance, with the latter compensating for the loss in enzymatic activity of the former, which in turn accounted for the restoration of viral replicative fitness, as observed previously3. Such a profile was also observed for ensitrelvir, another clinically relevant Mpro inhibitor. These results shed light on the mechanisms by which SARS-CoV-2 evolves to develop resistance to the current generation of protease inhibitors and provide the basis for the design of next-generation Mpro inhibitors.


Subject(s)
Antiviral Agents , Drug Resistance, Viral , SARS-CoV-2 , Humans , Antiviral Agents/chemistry , Antiviral Agents/metabolism , Antiviral Agents/pharmacology , COVID-19/virology , Lactams , Leucine , Nitriles , SARS-CoV-2/drug effects , SARS-CoV-2/enzymology , SARS-CoV-2/genetics , SARS-CoV-2/growth & development , Drug Resistance, Viral/drug effects , Drug Resistance, Viral/genetics , Binding Sites/drug effects , Binding Sites/genetics , Mutation , Substrate Specificity , Coronavirus 3C Proteases/antagonists & inhibitors , Coronavirus 3C Proteases/genetics , Coronavirus 3C Proteases/metabolism , Virus Replication/drug effects , Drug Design , Proline
7.
Plant Cell ; 36(6): 2238-2252, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38367203

ABSTRACT

During base excision repair (BER), the apurinic or apyrimidinic (AP) site serves as an intermediate product following base excision. In plants, APE-redox protein (ARP) represents the major AP site of cleavage activity. Despite the well-established understanding that the nucleosomal structure acts as a barrier to various DNA-templated processes, the regulatory mechanisms underlying BER at the chromatin level remain elusive, especially in plants. In this study, we identified plant chromatin remodeler Excision Repair Cross-Complementing protein group 6 (ERCC6) and histone chaperone Nucleosome Assembly Protein 1 (NAP1) as interacting proteins with ARP. The catalytic ATPase domain of ERCC6 facilitates its interaction with both ARP and NAP1. Additionally, ERCC6 and NAP1 synergistically contribute to nucleosome sliding and exposure of hindered endonuclease cleavage sites. Loss-of-function mutations in Arabidopsis (Arabidopsis thaliana) ERCC6 or NAP1 resulted in arp-dependent plant hypersensitivity to 5-fluorouracil, a toxic agent inducing BER, and the accumulation of AP sites. Furthermore, similar protein interactions are also found in yeast cells, suggesting a conserved recruitment mechanism employed by the AP endonuclease to overcome chromatin barriers during BER progression.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Chromatin Assembly and Disassembly , DNA Repair , Nucleosome Assembly Protein 1 , Arabidopsis/genetics , Arabidopsis/metabolism , Arabidopsis Proteins/metabolism , Arabidopsis Proteins/genetics , DNA Repair/genetics , Endonucleases/metabolism , Endonucleases/genetics , Nucleosome Assembly Protein 1/metabolism , Nucleosome Assembly Protein 1/genetics , Nucleosomes/metabolism
8.
J Immunol ; 213(2): 204-213, 2024 07 15.
Article in English | MEDLINE | ID: mdl-38856712

ABSTRACT

Bats are the natural reservoir hosts of some viruses, some of which may spill over to humans and cause global-scale pandemics. Different from humans, bats may coexist with high pathogenic viruses without showing symptoms of diseases. As one of the most important first defenses, bat type I IFNs (IFN-Is) were thought to play a role during this virus coexistence and thus were studied in recent years. However, there are arguments about whether bats have a contracted genome locus or constitutively expressed IFNs, mainly due to species-specific findings. We hypothesized that because of the lack of pan-bat analysis, the common characteristics of bat IFN-Is have not been revealed yet. In this study, we characterized the IFN-I locus for nine Yangochiroptera bats and three Yinpterochiroptera bats on the basis of their high-quality bat genomes. We also compared the basal expression in six bats and compared the antiviral and antiproliferative activity and the thermostability of representative Rhinolophus bat IFNs. We found a dominance of unconventional IFNω-like responses in the IFN-I system, which is unique to bats. In contrast to IFNα-dominated IFN-I loci in the majority of other mammals, bats generally have shorter IFN-I loci with more unconventional IFNω-like genes (IFNω or related IFNαω), but with fewer or even no IFNα genes. In addition, bats generally have constitutively expressed IFNs, the highest expressed of which is more likely an IFNω-like gene. Likewise, the highly expressed IFNω-like protein also demonstrated the best antiviral activity, antiproliferative activity, or thermostability, as shown in a representative Rhinolophus bat species. Overall, we revealed pan-bat unique, to our knowledge, characteristics in the IFN-I system, which provide insights into our understanding of the innate immunity that contributes to a special coexistence between bats and viruses.


Subject(s)
Chiroptera , Interferon Type I , Chiroptera/immunology , Chiroptera/genetics , Chiroptera/virology , Animals , Interferon Type I/genetics , Interferon Type I/immunology , Humans , Antiviral Agents , Immunity, Innate/genetics , Phylogeny
9.
Nature ; 579(7798): 270-273, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32015507

ABSTRACT

Since the outbreak of severe acute respiratory syndrome (SARS) 18 years ago, a large number of SARS-related coronaviruses (SARSr-CoVs) have been discovered in their natural reservoir host, bats1-4. Previous studies have shown that some bat SARSr-CoVs have the potential to infect humans5-7. Here we report the identification and characterization of a new coronavirus (2019-nCoV), which caused an epidemic of acute respiratory syndrome in humans in Wuhan, China. The epidemic, which started on 12 December 2019, had caused 2,794 laboratory-confirmed infections including 80 deaths by 26 January 2020. Full-length genome sequences were obtained from five patients at an early stage of the outbreak. The sequences are almost identical and share 79.6% sequence identity to SARS-CoV. Furthermore, we show that 2019-nCoV is 96% identical at the whole-genome level to a bat coronavirus. Pairwise protein sequence analysis of seven conserved non-structural proteins domains show that this virus belongs to the species of SARSr-CoV. In addition, 2019-nCoV virus isolated from the bronchoalveolar lavage fluid of a critically ill patient could be neutralized by sera from several patients. Notably, we confirmed that 2019-nCoV uses the same cell entry receptor-angiotensin converting enzyme II (ACE2)-as SARS-CoV.


Subject(s)
Betacoronavirus/classification , Betacoronavirus/genetics , Chiroptera/virology , Coronavirus Infections/epidemiology , Coronavirus Infections/virology , Disease Outbreaks , Pneumonia, Viral/epidemiology , Pneumonia, Viral/virology , Angiotensin-Converting Enzyme 2 , Animals , Antibodies, Viral/blood , Betacoronavirus/metabolism , Betacoronavirus/ultrastructure , COVID-19 , Cell Line , China/epidemiology , Chlorocebus aethiops , Female , Genome, Viral/genetics , Humans , Male , Peptidyl-Dipeptidase A/metabolism , Phylogeny , Severe acute respiratory syndrome-related coronavirus/classification , Severe acute respiratory syndrome-related coronavirus/genetics , SARS-CoV-2 , Sequence Homology, Nucleic Acid , Severe Acute Respiratory Syndrome , Vero Cells
10.
Nature ; 580(7801): 93-99, 2020 04.
Article in English | MEDLINE | ID: mdl-32238934

ABSTRACT

Prostate cancer is the second most common cancer in men worldwide1. Over the past decade, large-scale integrative genomics efforts have enhanced our understanding of this disease by characterizing its genetic and epigenetic landscape in thousands of patients2,3. However, most tumours profiled in these studies were obtained from patients from Western populations. Here we produced and analysed whole-genome, whole-transcriptome and DNA methylation data for 208 pairs of tumour tissue samples and matched healthy control tissue from Chinese patients with primary prostate cancer. Systematic comparison with published data from 2,554 prostate tumours revealed that the genomic alteration signatures in Chinese patients were markedly distinct from those of Western cohorts: specifically, 41% of tumours contained mutations in FOXA1 and 18% each had deletions in ZNF292 and CHD1. Alterations of the genome and epigenome were correlated and were predictive of disease phenotype and progression. Coding and noncoding mutations, as well as epimutations, converged on pathways that are important for prostate cancer, providing insights into this devastating disease. These discoveries underscore the importance of including population context in constructing comprehensive genomic maps for disease.


Subject(s)
Asian People/genetics , Epigenesis, Genetic , Epigenomics , Genome, Human/genetics , Genomics , Mutation , Prostatic Neoplasms/classification , Prostatic Neoplasms/genetics , Carrier Proteins/genetics , Cell Transformation, Neoplastic/genetics , China , Cohort Studies , DNA Helicases/genetics , DNA Methylation , DNA-Binding Proteins/genetics , Gene Expression Regulation, Neoplastic , Hepatocyte Nuclear Factor 3-alpha/genetics , Humans , Male , Nerve Tissue Proteins/genetics , Prostatic Neoplasms/pathology , RNA-Seq , Transcriptome/genetics
11.
Nucleic Acids Res ; 52(7): 3950-3970, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38281181

ABSTRACT

The common oral microbe Fusobacterium nucleatum has recently drawn attention after it was found to colonize tumors throughout the human body. Fusobacteria are also interesting study systems for bacterial RNA biology as these early-branching species encode many small noncoding RNAs (sRNAs) but lack homologs of the common RNA-binding proteins (RBPs) CsrA, Hfq and ProQ. To search for alternate sRNA-associated RBPs in F. nucleatum, we performed a systematic mass spectrometry analysis of proteins that co-purified with 19 different sRNAs. This approach revealed strong enrichment of the KH domain proteins KhpA and KhpB with nearly all tested sRNAs, including the σE-dependent sRNA FoxI, a regulator of several envelope proteins. KhpA/B act as a dimer to bind sRNAs with low micromolar affinity and influence the stability of several of their target transcripts. Transcriptome studies combined with biochemical and genetic analyses suggest that KhpA/B have several physiological functions, including being required for ethanolamine utilization. Our RBP search and the discovery of KhpA/B as major RBPs in F. nucleatum are important first steps in identifying key players of post-transcriptional control at the root of the bacterial phylogenetic tree.


Subject(s)
Bacterial Proteins , Fusobacterium nucleatum , RNA, Bacterial , RNA, Small Untranslated , RNA-Binding Proteins , Fusobacterium nucleatum/genetics , Fusobacterium nucleatum/metabolism , RNA-Binding Proteins/metabolism , RNA-Binding Proteins/genetics , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , RNA, Small Untranslated/metabolism , RNA, Small Untranslated/genetics , RNA, Small Untranslated/chemistry , RNA, Bacterial/metabolism , RNA, Bacterial/genetics , Gene Expression Regulation, Bacterial , Protein Binding , Mass Spectrometry
12.
Nucleic Acids Res ; 52(D1): D285-D292, 2024 Jan 05.
Article in English | MEDLINE | ID: mdl-37897340

ABSTRACT

Chromatin accessibility profiles at single cell resolution can reveal cell type-specific regulatory programs, help dissect highly specialized cell functions and trace cell origin and evolution. Accurate cell type assignment is critical for effectively gaining biological and pathological insights, but is difficult in scATAC-seq. Hence, by extensively reviewing the literature, we designed scATAC-Ref (https://bio.liclab.net/scATAC-Ref/), a manually curated scATAC-seq database aimed at providing a comprehensive, high-quality source of chromatin accessibility profiles with known cell labels across broad cell types. Currently, scATAC-Ref comprises 1 694 372 cells with known cell labels, across various biological conditions, >400 cell/tissue types and five species. We used uniform system environment and software parameters to perform comprehensive downstream analysis on these chromatin accessibility profiles with known labels, including gene activity score, TF enrichment score, differential chromatin accessibility regions, pathway/GO term enrichment analysis and co-accessibility interactions. The scATAC-Ref also provided a user-friendly interface to query, browse and visualize cell types of interest, thereby providing a valuable resource for exploring epigenetic regulation in different tissues and cell types.


Subject(s)
Chromatin Immunoprecipitation Sequencing , Chromatin , Databases, Genetic , Single-Cell Analysis , Chromatin/genetics , Epigenesis, Genetic , Humans , Animals
13.
Nucleic Acids Res ; 52(D1): D1614-D1628, 2024 Jan 05.
Article in English | MEDLINE | ID: mdl-37953341

ABSTRACT

Plants are unique with tremendous chemical diversity and metabolic complexity, which is highlighted by estimates that green plants collectively produce metabolites numbering in the millions. Plant metabolites play crucial roles in all aspects of plant biology, like growth, development, stress responses, etc. However, the lack of a reference metabolome for plants, and paucity of high-quality standard compound spectral libraries and related analytical tools, have hindered the discovery and functional study of phytochemicals in plants. Here, by leveraging an advanced LC-MS platform, we generated untargeted mass spectral data from >150 plant species collected across the five major phyla. Using a self-developed computation protocol, we constructed reference metabolome for 153 plant species. A 'Reference Metabolome Database for Plants' (RefMetaPlant) was built to encompass the reference metabolome, integrated standard compound mass spectral libraries for annotation, and related query and analytical tools like 'LC-MS/MS Query', 'RefMetaBlast' and 'CompoundLibBlast' for searches and profiling of plant metabolome and metabolite identification. Analogous to a reference genome in genomic research, RefMetaPlant provides a powerful platform to support plant genome-scale metabolite analysis to promote knowledge/data sharing and collaboration in the field of metabolomics. RefMetaPlant is freely available at https://www.biosino.org/RefMetaDB/.


Subject(s)
Databases, Factual , Metabolome , Chromatography, Liquid , Metabolome/genetics , Metabolomics/methods , Plants/metabolism , Tandem Mass Spectrometry
14.
Genes Dev ; 32(5-6): 430-447, 2018 03 01.
Article in English | MEDLINE | ID: mdl-29549180

ABSTRACT

The p53 tumor suppressor protein is the most well studied as a regulator of transcription in the nucleus, where it exists primarily as a tetramer. However, there are other oligomeric states of p53 that are relevant to its regulation and activities. In unstressed cells, p53 is normally held in check by MDM2 that targets p53 for transcriptional repression, proteasomal degradation, and cytoplasmic localization. Here we discovered a hydrophobic region within the MDM2 N-terminal domain that binds exclusively to the dimeric form of the p53 C-terminal domain in vitro. In cell-based assays, MDM2 exhibits superior binding to, hyperdegradation of, and increased nuclear exclusion of dimeric p53 when compared with tetrameric wild-type p53. Correspondingly, impairing the hydrophobicity of the newly identified N-terminal MDM2 region leads to p53 stabilization. Interestingly, we found that dimeric mutant p53 is partially unfolded and is a target for ubiquitin-independent degradation by the 20S proteasome. Finally, forcing certain tumor-derived mutant forms of p53 into dimer configuration results in hyperdegradation of mutant p53 and inhibition of p53-mediated cancer cell migration. Gaining insight into different oligomeric forms of p53 may provide novel approaches to cancer therapy.


Subject(s)
Neoplasms/physiopathology , Proto-Oncogene Proteins c-mdm2/metabolism , Tumor Suppressor Protein p53/metabolism , Cell Line, Tumor , Cytoplasm/metabolism , Humans , Hydrophobic and Hydrophilic Interactions , Mutation , Proteasome Endopeptidase Complex/metabolism , Protein Binding , Protein Domains , Protein Multimerization/genetics , Proteolysis , Tumor Suppressor Protein p53/chemistry , Tumor Suppressor Protein p53/genetics
15.
J Neurosci ; 44(28)2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38830763

ABSTRACT

Chronic sleep disruption (CSD), from insufficient or fragmented sleep and is an important risk factor for Alzheimer's disease (AD). Underlying mechanisms are not understood. CSD in mice results in degeneration of locus ceruleus neurons (LCn) and CA1 hippocampal neurons and increases hippocampal amyloid-ß42 (Aß42), entorhinal cortex (EC) tau phosphorylation (p-tau), and glial reactivity. LCn injury is increasingly implicated in AD pathogenesis. CSD increases NE turnover in LCn, and LCn norepinephrine (NE) metabolism activates asparagine endopeptidase (AEP), an enzyme known to cleave amyloid precursor protein (APP) and tau into neurotoxic fragments. We hypothesized that CSD would activate LCn AEP in an NE-dependent manner to induce LCn and hippocampal injury. Here, we studied LCn, hippocampal, and EC responses to CSD in mice deficient in NE [dopamine ß-hydroxylase (Dbh)-/-] and control male and female mice, using a model of chronic fragmentation of sleep (CFS). Sleep was equally fragmented in Dbh -/- and control male and female mice, yet only Dbh -/- mice conferred resistance to CFS loss of LCn, LCn p-tau, and LCn AEP upregulation and activation as evidenced by an increase in AEP-cleaved APP and tau fragments. Absence of NE also prevented a CFS increase in hippocampal AEP-APP and Aß42 but did not prevent CFS-increased AEP-tau and p-tau in the EC. Collectively, this work demonstrates AEP activation by CFS, establishes key roles for NE in both CFS degeneration of LCn neurons and CFS promotion of forebrain Aß accumulation, and, thereby, identifies a key molecular link between CSD and specific AD neural injuries.


Subject(s)
Amyloid beta-Peptides , Cysteine Endopeptidases , Hippocampus , Locus Coeruleus , Norepinephrine , Sleep Deprivation , Animals , Amyloid beta-Peptides/metabolism , Norepinephrine/metabolism , Mice , Hippocampus/metabolism , Hippocampus/pathology , Sleep Deprivation/metabolism , Sleep Deprivation/pathology , Male , Locus Coeruleus/metabolism , Locus Coeruleus/pathology , Cysteine Endopeptidases/metabolism , Cysteine Endopeptidases/genetics , Peptide Fragments/metabolism , Mice, Inbred C57BL , Mice, Knockout , Dopamine beta-Hydroxylase/metabolism , Dopamine beta-Hydroxylase/genetics , tau Proteins/metabolism , Female , Nerve Degeneration/pathology , Nerve Degeneration/metabolism , Nerve Degeneration/genetics
16.
Plant J ; 2024 Aug 19.
Article in English | MEDLINE | ID: mdl-39158506

ABSTRACT

C-glycosides are a predominant class of flavonoids that demonstrate diverse medical properties and plant physiological functions. The chemical stability, structural diversity, and differential aboveground distribution of these compounds in plants make them ideal protectants. However, little is known about the transcriptional regulatory mechanisms that play these diverse roles in plant physiology. In this study, chard was selected from 69 families for its significantly different flavonoid C-glycosides distributions between the aboveground and underground parts to investigate the role and regulatory mechanism of flavonoid C-glycosides in plants. Our results indicate that flavonoid C-glycosides are affected by various stressors, especially UV-B. Through cloning and validation of key biosynthetic genes of flavonoid C-glycosides in chard (BvCGT1), we observed significant effects induced by UV-B radiation. This finding was further confirmed by resistance testing in BvCGT1 silenced chard lines and in Arabidopsis plants with BvCGT1 overexpression. Yeast one-hybrid and dual-luciferase assays were employed to determine the underlying regulatory mechanisms of BvCGT1 in withstanding UV-B stress. These results indicate a potential regulatory role of BvDof8 and BvDof13 in modulating flavonoid C-glycosides content, through their influence on BvCGT1. In conclusion, we have effectively demonstrated the regulation of BvCGT1 by BvDof8 and BvDof13, highlighting their crucial role in plant adaptation to UV-B radiation. Additionally, we have outlined a comprehensive transcriptional regulatory network involving BvDof8 and BvDof13 in response to UV-B radiation.

17.
Plant J ; 119(3): 1613-1626, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38818975

ABSTRACT

Chemical compositions of crops are of great agronomical importance, as crops serve as resources for nutrition, energy, and medicines for human and livestock. For crop metabolomics research, the lack of crop reference metabolome and high-quality reference compound mass spectra, as well as utilities for metabolic profiling, has hindered the discovery and functional study of phytochemicals in crops. To meet these challenging needs, we have developed the Crop Metabolome database (abbreviated as CropMetabolome) that is dedicated to the construction of crop reference metabolome, repository, and dissemination of crop metabolomic data, and profiling and analytic tools for metabolomics research. CropMetabolome contains a metabolomics database for more than 50 crops (belonging to eight categories) that integrated self-generated raw mass spectral data and public-source datasets. The reference metabolome for 59 crop species was constructed, which have functions that parallel those of reference genome in genomic studies. CropMetabolome also contains 'Standard compound mass spectral library', 'Flavonoids library', 'Pesticide library', and a set of related analytical tools that enable metabolic profiling based on a reference metabolome (CropRefMetaBlast), annotation and identification of new metabolites (CompoundLibBlast), deducing the structure of novel flavonoid derivatives (FlavoDiscover), and detecting possible residual pesticides in crop samples (PesticiDiscover). In addition, CropMetabolome is a repository to share and disseminate metabolomics data and a platform to promote collaborations to develop reference metabolome for more crop species. CropMetabolome is a comprehensive platform that offers important functions in crop metabolomics research and contributes to improve crop breeding, nutrition, and safety. CropMetabolome is freely available at https://www.cropmetabolome.com/.


Subject(s)
Crops, Agricultural , Databases, Factual , Metabolome , Metabolomics , Crops, Agricultural/metabolism , Crops, Agricultural/genetics , Metabolomics/methods , Flavonoids/metabolism , Mass Spectrometry
18.
Brief Bioinform ; 24(4)2023 07 20.
Article in English | MEDLINE | ID: mdl-37291763

ABSTRACT

BACKGROUND: Promoters are DNA regions that initiate the transcription of specific genes near the transcription start sites. In bacteria, promoters are recognized by RNA polymerases and associated sigma factors. Effective promoter recognition is essential for synthesizing the gene-encoded products by bacteria to grow and adapt to different environmental conditions. A variety of machine learning-based predictors for bacterial promoters have been developed; however, most of them were designed specifically for a particular species. To date, only a few predictors are available for identifying general bacterial promoters with limited predictive performance. RESULTS: In this study, we developed TIMER, a Siamese neural network-based approach for identifying both general and species-specific bacterial promoters. Specifically, TIMER uses DNA sequences as the input and employs three Siamese neural networks with the attention layers to train and optimize the models for a total of 13 species-specific and general bacterial promoters. Extensive 10-fold cross-validation and independent tests demonstrated that TIMER achieves a competitive performance and outperforms several existing methods on both general and species-specific promoter prediction. As an implementation of the proposed method, the web server of TIMER is publicly accessible at http://web.unimelb-bioinfortools.cloud.edu.au/TIMER/.


Subject(s)
Bacteria , Neural Networks, Computer , Bacteria/genetics , Bacteria/metabolism , DNA-Directed RNA Polymerases/genetics , DNA-Directed RNA Polymerases/metabolism , Base Sequence , Promoter Regions, Genetic
19.
Plant Cell ; 34(3): 1100-1116, 2022 03 04.
Article in English | MEDLINE | ID: mdl-34954802

ABSTRACT

Chromatin remodelers act in an ATP-dependent manner to modulate chromatin structure and thus genome function. Here, we report that the Arabidopsis (Arabidopsis thaliana) remodeler CHROMATIN REMODELING19 (CHR19) is enriched in gene body regions, and its depletion causes massive changes in nucleosome position and occupancy in the genome. Consistent with these changes, an in vitro assay verified that CHR19 can utilize ATP to slide nucleosomes. A variety of inducible genes, including several important genes in the salicylic acid (SA) and jasmonic acid (JA) pathways, were transcriptionally upregulated in the chr19 mutant under normal growth conditions, indicative of a role of CHR19 in transcriptional repression. In addition, the chr19 mutation triggered higher susceptibility to the JA pathway-defended necrotrophic fungal pathogen Botrytis cinerea, but did not affect the growth of the SA pathway-defended hemibiotrophic bacterial pathogen Pseudomonas syringae pv. tomato DC3000. Expression of CHR19 was tissue-specific and inhibited specifically by SA treatment. Such inhibition significantly decreased the local chromatin enrichment of CHR19 at the associated SA pathway genes, which resulted in their full activation upon SA treatment. Overall, our findings clarify CHR19 to be a novel regulator acting at the chromatin level to impact the transcription of genes underlying plant resistance to different pathogens.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Adenosine Triphosphate/metabolism , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Botrytis/genetics , Chromatin/genetics , Chromatin/metabolism , Chromatin Assembly and Disassembly/genetics , Cyclopentanes/metabolism , Gene Expression Regulation, Plant/genetics , Oxylipins/metabolism , Plant Diseases/genetics , Plant Diseases/microbiology , Pseudomonas syringae/physiology , Salicylic Acid/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism
20.
FASEB J ; 38(2): e23414, 2024 01 31.
Article in English | MEDLINE | ID: mdl-38236371

ABSTRACT

Increasing evidence has demonstrated that the expression of coil domains containing 25 (CCDC25) in various malignancies is abnormally high. However, the potential regulatory role and mechanism of CCDC25 in the development of clear cell renal cell carcinoma (ccRCC) are still unclear. In this experiment, we combined in vitro experiments such as wound healing, CCK8, and transwell assay with in vivo experiments on tumor formation in nude mice to evaluate the effect of CCDC25 on the proliferation, migration, and invasion of renal cancer cells. In addition, we also used Western blotting and qPCR to evaluate the role of CCDC25 in activating the integrin-linked kinase (ILK)-NF-κB signaling pathway. Here, we demonstrate that compared to normal tissues and cell lines, CCDC25 is overexpressed in both human ccRCC tissues and cell lines. After CCDC25 knockdown, it has obvious inhibitory effect on the proliferation, migration, and invasion of cancer cells in vitro and in vivo. In contrast, CCDC25 overexpression promotes these effects. Additionally, we also discovered that CCDC25 interacts with ILK and coordinates the activation of the NF-κB signaling pathway downstream. Generally, our study suggests that CCDC25 plays a vital role in the development of ccRCC, which also means that it may be a potential therapeutic target for ccRCC.


Subject(s)
Carcinoma, Renal Cell , Kidney Neoplasms , Membrane Proteins , Animals , Humans , Mice , Carcinoma, Renal Cell/genetics , Cell Proliferation , Kidney Neoplasms/genetics , Mice, Nude , NF-kappa B/metabolism , Protein Serine-Threonine Kinases/metabolism , Signal Transduction , Membrane Proteins/metabolism
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