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1.
Mol Cell ; 69(5): 773-786.e6, 2018 03 01.
Article in English | MEDLINE | ID: mdl-29499133

ABSTRACT

Skp1⋅Cul1⋅F-box (SCF) ubiquitin ligase assembly is regulated by the interplay of substrate binding, reversible Nedd8 conjugation on Cul1, and the F-box protein (FBP) exchange factors Cand1 and Cand2. Detailed investigations into SCF assembly and function in reconstituted systems and Cand1/2 knockout cells informed the development of a mathematical model for how dynamical assembly of SCF complexes is controlled and how this cycle is coupled to degradation of an SCF substrate. Simulations predicted an unanticipated hypersensitivity of Cand1/2-deficient cells to FBP expression levels, which was experimentally validated. Together, these and prior observations lead us to propose the adaptive exchange hypothesis, which posits that regulation of the koff of an FBP from SCF by the actions of substrate, Nedd8, and Cand1 molds the cellular repertoire of SCF complexes and that the plasticity afforded by this exchange mechanism may enable large variations in FBP expression during development and in FBP gene number during evolution.


Subject(s)
F-Box Proteins , Gene Expression Regulation , Models, Biological , Models, Chemical , Proteolysis , Transcription Factors , Animals , Cullin Proteins/chemistry , Cullin Proteins/genetics , Cullin Proteins/metabolism , F-Box Proteins/biosynthesis , F-Box Proteins/chemistry , F-Box Proteins/genetics , Mice , NEDD8 Protein/chemistry , NEDD8 Protein/genetics , NEDD8 Protein/metabolism , Transcription Factors/chemistry , Transcription Factors/genetics , Transcription Factors/metabolism
2.
Brief Bioinform ; 24(1)2023 01 19.
Article in English | MEDLINE | ID: mdl-36642414

ABSTRACT

The proliferation of single-cell multimodal sequencing technologies has enabled us to understand cellular heterogeneity with multiple views, providing novel and actionable biological insights into the disease-driving mechanisms. Here, we propose a comprehensive end-to-end single-cell multimodal analysis framework named Deep Parametric Inference (DPI). DPI transforms single-cell multimodal data into a multimodal parameter space by inferring individual modal parameters. Analysis of cord blood mononuclear cells (CBMC) reveals that the multimodal parameter space can characterize the heterogeneity of cells more comprehensively than individual modalities. Furthermore, comparisons with the state-of-the-art methods on multiple datasets show that DPI has superior performance. Additionally, DPI can reference and query cell types without batch effects. As a result, DPI can successfully analyze the progression of COVID-19 disease in peripheral blood mononuclear cells (PBMC). Notably, we further propose a cell state vector field and analyze the transformation pattern of bone marrow cells (BMC) states. In conclusion, DPI is a powerful single-cell multimodal analysis framework that can provide new biological insights into biomedical researchers. The python packages, datasets and user-friendly manuals of DPI are freely available at https://github.com/studentiz/dpi.


Subject(s)
COVID-19 , Leukocytes, Mononuclear , Humans , Single-Cell Analysis/methods , Computational Biology/methods
3.
Bioinformatics ; 40(1)2024 01 02.
Article in English | MEDLINE | ID: mdl-38141207

ABSTRACT

MOTIVATION: The utilization of single-cell bisulfite sequencing (scBS-seq) methods allows for precise analysis of DNA methylation patterns at the individual cell level, enabling the identification of rare populations, revealing cell-specific epigenetic changes, and improving differential methylation analysis. Nonetheless, the presence of sparse data and an overabundance of zeros and ones, attributed to limited sequencing depth and coverage, frequently results in reduced precision accuracy during the process of differential methylation detection using scBS-seq. Consequently, there is a pressing demand for an innovative differential methylation analysis approach that effectively tackles these data characteristics and enhances recognition accuracy. RESULTS: We propose a novel beta mixture approach called scDMV for analyzing methylation differences in single-cell bisulfite sequencing data, which effectively handles excess zeros and ones and accommodates low-input sequencing. Our extensive simulation studies demonstrate that the scDMV approach outperforms several alternative methods in terms of sensitivity, precision, and controlling the false positive rate. Moreover, in real data applications, we observe that scDMV exhibits higher precision and sensitivity in identifying differentially methylated regions, even with low-input samples. In addition, scDMV reveals important information for GO enrichment analysis with single-cell whole-genome sequencing data that are often overlooked by other methods. AVAILABILITY AND IMPLEMENTATION: The scDMV method, along with a comprehensive tutorial, can be accessed as an R package on the following GitHub repository: https://github.com/PLX-m/scDMV.


Subject(s)
DNA Methylation , Sulfites , Sequence Analysis, DNA/methods , Whole Genome Sequencing
4.
Nucleic Acids Res ; 51(D1): D1483-D1491, 2023 01 06.
Article in English | MEDLINE | ID: mdl-36271793

ABSTRACT

Over the last decade, RNA-seq has produced a massive amount of plant transcriptomic sequencing data deposited in public databases. Reanalysis of these public datasets can generate additional novel hypotheses not included in original studies. However, the large data volume and the requirement for specialized computational resources and expertise present a barrier for experimental biologists to explore public repositories. Here, we introduce PlantExp (https://biotec.njau.edu.cn/plantExp), a database platform for exploration of plant gene expression and alternative splicing profiles based on 131 423 uniformly processed publicly available RNA-seq samples from 85 species in 24 plant orders. In addition to two common retrieval accesses to gene expression and alternative splicing profiles by functional terms and sequence similarity, PlantExp is equipped with four online analysis tools, including differential expression analysis, specific expression analysis, co-expression network analysis and cross-species expression conservation analysis. With these online analysis tools, users can flexibly customize sample groups to reanalyze public RNA-seq datasets and obtain new insights. Furthermore, it offers a wide range of visualization tools to help users intuitively understand analysis results. In conclusion, PlantExp provides a valuable data resource and analysis platform for plant biologists to utilize public RNA-seq. datasets.


Subject(s)
Alternative Splicing , Plants , Transcriptome , Alternative Splicing/genetics , RNA, Plant/genetics , RNA-Seq , Sequence Analysis, RNA/methods , Software , Transcriptome/genetics , Plants/genetics
5.
Proc Natl Acad Sci U S A ; 119(36): e2205608119, 2022 09 06.
Article in English | MEDLINE | ID: mdl-36037385

ABSTRACT

Cop9 signalosome (CSN) regulates the function of cullin-RING E3 ubiquitin ligases (CRLs) by deconjugating the ubiquitin-like protein NEDD8 from the cullin subunit. To understand the physiological impact of CSN function on the CRL network and cell proliferation, we combined quantitative mass spectrometry and genome-wide CRISPR interference (CRISPRi) and CRISPR activation (CRISPRa) screens to identify factors that modulate cell viability upon inhibition of CSN by the small molecule CSN5i-3. CRL components and regulators strongly modulated the antiproliferative effects of CSN5i-3, and in addition we found two pathways involved in genome integrity, SCFFBXO5-APC/C-GMNN and CUL4DTL-SETD8, that contribute substantially to the toxicity of CSN inhibition. Our data highlight the importance of CSN-mediated NEDD8 deconjugation and adaptive exchange of CRL substrate receptors in sustaining CRL function and suggest approaches for leveraging CSN inhibition for the treatment of cancer.


Subject(s)
DNA Replication , Ubiquitin-Protein Ligases , Azepines/metabolism , COP9 Signalosome Complex/antagonists & inhibitors , COP9 Signalosome Complex/genetics , COP9 Signalosome Complex/metabolism , Cell Survival , Cullin Proteins/genetics , Cullin Proteins/metabolism , Imidazoles/metabolism , NEDD8 Protein/metabolism , Pyrazoles/metabolism , Ubiquitin-Protein Ligases/genetics , Ubiquitin-Protein Ligases/metabolism
6.
J Cell Mol Med ; 28(7): e18200, 2024 04.
Article in English | MEDLINE | ID: mdl-38506069

ABSTRACT

Diabetic retinopathy (DR) is one of leading causes of vision loss in adults with increasing prevalence worldwide. Increasing evidence has emphasized the importance of gut microbiome in the aetiology and development of DR. However, the causal relationship between gut microbes and DR remains largely unknown. To investigate the causal associations of DR with gut microbes and DR risk factors, we employed two-sample Mendelian Randomization (MR) analyses to estimate the causal effects of 207 gut microbes on DR outcomes. Inputs for MR included Genome-wide Association Study (GWAS) summary statistics of 207 taxa of gut microbes (the Dutch Microbiome Project) and 21 risk factors for DR. The GWAS summary statistics data of DR was from the FinnGen Research Project. Data analysis was performed in May 2023. We identified eight bacterial taxa that exhibited significant causal associations with DR (FDR < 0.05). Among them, genus Collinsella and species Collinsella aerofaciens were associated with increased risk of DR, while the species Bacteroides faecis, Burkholderiales bacterium_1_1_47, Ruminococcus torques, Streptococcus salivarius, genus Burkholderiales_noname and family Burkholderiales_noname showed protective effects against DR. Notably, we found that the causal effect of species Streptococcus salivarius on DR was mediated through the level of host fasting glucose, a well-established risk factor for DR. Our results reveal that specific gut microbes may be causally linked to DR via mediating host metabolic risk factors, highlighting potential novel therapeutic or preventive targets for DR.


Subject(s)
Diabetes Mellitus , Diabetic Retinopathy , Streptococcus salivarius , Adult , Humans , Mendelian Randomization Analysis , Genome-Wide Association Study , Fasting , Glucose
7.
Bioinformatics ; 39(1)2023 01 01.
Article in English | MEDLINE | ID: mdl-36655761

ABSTRACT

SUMMARY: Fungi form a large and heterogeneous group of eukaryotic organisms with diverse ecological niches. The high importance of fungi contrasts with our limited understanding of fungal lifestyle and adaptability to environment. Over the last decade, the high-throughput sequencing technology produced tremendous RNA-sequencing (RNA-seq) data. However, there is no comprehensive database for mycologists to conveniently explore fungal gene expression and alternative splicing. Here, we have developed FungiExp, an online database including 35 821 curated RNA-seq samples derived from 220 fungal species, together with gene expression and alternative splicing profiles. It allows users to query and visualize gene expression and alternative splicing in the collected RNA-seq samples. Furthermore, FungiExp contains several online analysis tools, such as differential/specific, co-expression network and cross-species gene expression conservation analysis. Through these tools, users can obtain new insights by re-analyzing public RNA-seq data or upload personal data to co-analyze with public RNA-seq data. AVAILABILITY AND IMPLEMENTATION: The FungiExp is freely available at https://bioinfo.njau.edu.cn/fungiExp. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Subject(s)
Alternative Splicing , RNA , Sequence Analysis, RNA , Gene Expression Profiling , Gene Expression , Software
8.
Opt Express ; 32(4): 6104-6120, 2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38439321

ABSTRACT

We present a wide-field illumination time-domain (TD) diffusion optical tomography (DOT) for three-dimensional (3-D) reconstruction within a shallow region under the illuminated surface of the turbid medium. The methodological foundation is laid on the single-pixel spatial frequency domain (SFD) imaging that facilitates the adoption of the well-established time-correlated single-photon counting (TCSPC)-based TD detection and generalized pulse spectrum techniques (GPST)-based reconstruction. To ameliorate the defects of the conventional diffusion equation (DE) in the forward modeling of TD-SFD-DOT, mainly the low accuracy in the near-field region and in profiling early-photon migration, we propose a modified model employing the time-dependent δ-P1 approximation and verify its improved accuracy in comparison with both the Monte Carlo and DE-based ones. For a simplified inversion process, a modified GPST approach is extended to TD-SFD-DOT that enables the effective separation of the absorption and scattering coefficients using a steady-state equivalent strategy. Furthermore, we set up a single-pixel TD-SFD-DOT system that employs the TCSPC-based TD detection in the SFD imaging framework. For assessments of the reconstruction approach and the system performance, phantom experiments are performed for a series of scenarios. The results show the effectiveness of the proposed methodology for rapid 3-D reconstruction of the absorption and scattering coefficients within a depth range of about 5 mean free pathlengths.

9.
Opt Lett ; 49(4): 955, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38359225

ABSTRACT

This publisher's note contains a correction to Opt. Lett.48, 5443 (2023)10.1364/OL.495099.

10.
Chemistry ; 30(36): e202401171, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38646836

ABSTRACT

Stimuli-responsive crystalline materials have received much attention for being potential candidates of smart materials. However, the occurrence of polymorphism-driven stimuli responses in crystalline materials remains interesting but rare. Herein, three polymorphs of an acylhydrazone derivative, N'-[(E)-(1-benzofuran-2-yl) methylidene] pyridine -4-carbohydrazide (BFMP) were prepared. Form-1 undergoes a photomechanical response via E→Z photoisomerization under UV irradiation, accompanied by a decrease in fluorescence intensity and a change from colorless to yellow. Two types of Z→E thermal isomerization mechanisms with significant differences in conversion rate were observed at different temperatures in form-1. The solid-melt-solid transition has a faster conversion rate compared to the solid-solid transition due to freedom from lattice confinement. The transition from form-2 to form-3 can be achieved under grinding, coupled with a significant decrease in fluorescence intensity. The similar molecular stacking pattern of form-2 and form-3 provides a structural basis for the grinding-induced crystalline transition behavior. In addition, the presence of the pyridine moiety imparts an acidochromic property. The combination of photochromism and acidochromism explores the possible applications of acylhydrazone derivatives in information encryption.

11.
Mol Cell Biochem ; 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38980592

ABSTRACT

Melanoma is a primary malignant tumor with high lethality, which occurs in the skin and eye tissues, while the molecular mechanisms of melanomagenesis remain largely unknown. Here, we show that death-associated protein-like 1 (DAPL1) expression is lower in melanoma tissues than in paracancerous tissues or nevus tissues, and Uveal melanoma patients with lower DAPL1 expression have a poorer survival rate than those with higher expression of DAPL1. Overexpression of DAPL1 inhibits proliferation of cultured melanoma cells, whereas knockdown of DAPL1 increases cell proliferation. Tumor transplantation experiment results also demonstrate that DAPL1 inhibits tumorigenesis of melanoma cells both in subretinal and subcutaneous tissues of nude mice in vivo. Finally, DAPL1 inhibits proliferation of melanoma cells by increasing the protein level of P21 via decreasing the ubiquitin mediated degradation of P21 and promoting its stability. Conversely, knockdown of P21 neutralizes the effects of inhibition of DAPL1 on melanoma cell proliferation and enhances the severity of melanoma tumorigenesis. These results suggest that DAPL1 is a novel melanoma tumor suppressor gene and thus a potential therapeutic target for melanoma.

12.
Environ Sci Technol ; 58(24): 10458-10469, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38836430

ABSTRACT

Hepatic steatosis is the first step in a series of events that drives hepatic disease and has been considerably associated with exposure to fine particulate matter (PM2.5). Although the chemical constituents of particles matter in the negative health effects, the specific components of PM2.5 that trigger hepatic steatosis remain unclear. New strategies prioritizing the identification of the key components with the highest potential to cause adverse effects among the numerous components of PM2.5 are needed. Herein, we established a high-resolution mass spectrometry (MS) data set comprising the hydrophobic organic components corresponding to 67 PM2.5 samples in total from Taiyuan and Guangzhou, two representative cities in North and South China, respectively. The lipid accumulation bioeffect profiles of the above samples were also obtained. Considerable hepatocyte lipid accumulation was observed in most PM2.5 extracts. Subsequently, 40 of 695 components were initially screened through machine learning-assisted data filtering based on an integrated bioassay with MS data. Next, nine compounds were further selected as candidates contributing to hepatocellular steatosis based on absorption, distribution, metabolism, and excretion evaluation and molecular dockingin silico. Finally, seven components were confirmed in vitro. This study provided a multilevel screening strategy for key active components in PM2.5 and provided insight into the hydrophobic PM2.5 components that induce hepatocellular steatosis.


Subject(s)
Hydrophobic and Hydrophilic Interactions , Particulate Matter , Fatty Liver/chemically induced , Humans , China , Air Pollutants
13.
Phys Chem Chem Phys ; 26(7): 6429-6435, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38317609

ABSTRACT

The electrical tree in grafted polypropylene (PP) is inhibited compared with that of pure PP. To understand the free radicals that are generated during the treeing process, we study the electron paramagnetic resonance (EPR) spectra. Additionally, to provide a clearer explanation of the suppression of electrical trees, this research uses electroluminescence (EL) and excitation computation. These methods help us to observe the movement of electrons and to understand the geometric and electronic structures involved. In pure PP, the energy required to excite the electrons is approximately the same as the band gap of PP while electrons are easier to be excited in grafted PP than in pure PP, because the band gap is narrower. As a result, though the electrical tree length is shorter in PP-g-MMA, the EPR signal is more intense because of the uneven distribution of electrons.

14.
Bioorg Chem ; 145: 107219, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38377821

ABSTRACT

SET domain bifurcated methyltransferase 1 (SETDB1) serves as a histone lysine methyltransferase, catalyzing the di- and tri-methylation of histone H3K9. Mounting evidence indicates that the abnormal expression or activity of SETDB1, either through amplification or mutation, plays a crucial role in tumorigenesis and progression. This is particularly evident in the context of tumor immune evasion and resistance to immune checkpoint blockade therapy. Furthermore, there is a robust association between SETDB1 dysregulation and an unfavorable prognosis across various types of tumors. The oncogenic role of SETDB1 primarily arises from its methyltransferase function, which contributes to the establishment of a condensed and transcriptionally inactive heterochromatin state. This results in the inactivation of genes that typically hinder cancer development and silencing of retrotransposons that could potentially trigger an immune response. These findings underscore the substantial potential for SETDB1 as an anti-tumor therapeutic target. Nevertheless, despite significant strides in recent years in tumor biology research, challenges persist in SETDB1-targeted therapy. To better facilitate the development of anti-tumor therapy targeting SETDB1, we have conducted a comprehensive review of SETDB1 in this account. We present the structure and function of SETDB1, its role in various tumors and immune regulation, as well as the advancements made in SETDB1 antagonists. Furthermore, we discuss the challenges encountered and provide perspectives for the development of SETDB1-targeted anti-tumor therapy.


Subject(s)
Histones , Neoplasms , Humans , Histones/metabolism , Histone-Lysine N-Methyltransferase/genetics , Neoplasms/drug therapy , Methylation
15.
Environ Res ; 252(Pt 2): 118938, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38649014

ABSTRACT

Fly ash (FA) is mainly composed of silica, alumina, and other metal oxide components, and has a positive stabilizing effect on soil heavy metals. Biochar composites produced from FA and corn stover (CS) can improve its remediation performance. Therefore, a batch of biochar composites (alkali-fused FA-CS biochars, ABs), synthesized via co-pyrolysis of CS and alkali-fused FA (AFFA) at different temperatures of 300, 500, and 700 °C (AB300-1, AB500-1, and AB700-1) and CS to AFFA mass ratios of 10:1, 10:2, and 10:5 (AB500-1, AB500-2, and AB500-5), was used to remediate lead (Pb)-contaminated soil. Compared with pristine biochars (BCs), ABs were enriched with oxygen-containing functional groups (Si-O-Si and Si-O) and aromatic structures. The ABs prepared at lower pyrolytic temperature (≤500 °C) and lower ratio of CS to AFFA (10:1) showed higher yield and stability. The contents of Toxicity Characteristic Leaching Procedure (TCLP)-extractable Pb and DTPA-CaCl2-triethanolamine (DTPA)-extractable Pb were generally lower in the soils amended with ABs than BCs. Compared with other ABs such as AB300-1, AB500-2, AB500-5, and AB700-1, the soil amended with AB500-1 had lower contents of TCLP and DTPA-extractable Pb (24% reduction), exhibiting superior performance in stabilizing Pb in the soil. The gradual decrease of DTPA-extractable Pb content in the soil with increasing dosage of AB500-1 amendments suggests that AB500-1 facilitated the conversion of bioavailable Pb to the stable and less toxic residual fractions. Specifically, the highest percentage of residual fraction of Pb in soil amended with AB500-1 was 14%. Correlation analyses showed that the soil DTPA-extractable Pb content decreased with the increase of soil pH and cation-exchange capacity (CEC) value. ABs stabilize Pb in the soils mainly via electrostatic attraction, precipitation, cation-π interaction, cation exchange, and complexation. These findings provide insights for producing functionalized biochar composites from industrial waste like FA and biomass waste for remediating the soils polluted by heavy metals.


Subject(s)
Charcoal , Coal Ash , Environmental Restoration and Remediation , Lead , Pyrolysis , Soil Pollutants , Zea mays , Charcoal/chemistry , Zea mays/chemistry , Lead/chemistry , Lead/analysis , Coal Ash/chemistry , Soil Pollutants/chemistry , Soil Pollutants/analysis , Environmental Restoration and Remediation/methods , Alkalies/chemistry , Soil/chemistry
16.
Plant Cell Rep ; 43(2): 30, 2024 Jan 10.
Article in English | MEDLINE | ID: mdl-38195770

ABSTRACT

KEY MESSAGE: Sucrose invertase activity is positively related to osmotic and salt stress resistance in peanut. Sucrose invertases (INVs) have important functions in plant growth and response to environmental stresses. However, their biological roles in peanut are still not fully revealed. In this research, we identified 42 AhINV genes in the peanut genome. They were highly conserved and clustered into three groups with 24 segmental duplication events occurred under purifying selection. Transcriptional expression analysis exhibited that they were all ubiquitously expressed, and most of them were up-regulated by osmotic and salt stresses, with AhINV09, AhINV23 and AhINV19 showed the most significant up-regulation. Further physiochemical analysis showed that the resistance of peanut to osmotic and salt stress was positively related to the high sugar content and sucrose invertase activity. Our results provided fundamental information on the structure and evolutionary relationship of INV gene family in peanut and gave theoretical guideline for further functional study of AhINV genes in response to abiotic stress.


Subject(s)
Arachis , Sugars , Arachis/genetics , beta-Fructofuranosidase/genetics , Salt Stress , Sucrose
17.
Alzheimers Dement ; 20(5): 3251-3269, 2024 05.
Article in English | MEDLINE | ID: mdl-38501315

ABSTRACT

INTRODUCTION: Although glymphatic function is involved in Alzheimer's disease (AD), its potential for predicting the pathological and clinical progression of AD and its sequential association with core AD biomarkers is poorly understood. METHODS: Whole-brain glymphatic activity was measured by diffusion tensor image analysis along the perivascular space (DTI-ALPS) in participants with AD dementia (n = 47), mild cognitive impairment (MCI; n = 137), and normal controls (n = 235) from the Alzheimer's Disease Neuroimaging Initiative. RESULTS: ALPS index was significantly lower in AD dementia than in MCI or controls. Lower ALPS index was significantly associated with faster changes in amyloid positron emission tomography (PET) burden and AD signature region of interest volume, higher risk of amyloid-positive transition and clinical progression, and faster rates of amyloid- and neurodegeneration-related cognitive decline. Furthermore, the associations of the ALPS index with cognitive decline were fully mediated by amyloid PET and brain atrophy. DISCUSSION: Glymphatic failure may precede amyloid pathology, and predicts amyloid deposition, neurodegeneration, and clinical progression in AD. HIGHLIGHTS: The analysis along the perivascular space (ALPS) index is reduced in patients with Alzheimer's disease (AD) dementia, prodromal AD, and preclinical AD. Lower ALPS index predicted accelerated amyloid beta (Aß) positron emission tomography (PET) burden and Aß-positive transition. The decrease in the ALPS index occurs before cerebrospinal fluid Aß42 reaches the positive threshold. ALPS index predicted brain atrophy, clinical progression, and cognitive decline. Aß PET and brain atrophy mediated the link of ALPS index with cognitive decline.


Subject(s)
Alzheimer Disease , Brain , Cognitive Dysfunction , Disease Progression , Glymphatic System , Positron-Emission Tomography , Humans , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/pathology , Alzheimer Disease/metabolism , Female , Male , Glymphatic System/diagnostic imaging , Glymphatic System/pathology , Aged , Cognitive Dysfunction/metabolism , Cognitive Dysfunction/diagnostic imaging , Cognitive Dysfunction/pathology , Brain/diagnostic imaging , Brain/pathology , Brain/metabolism , Amyloid beta-Peptides/metabolism , Amyloid beta-Peptides/cerebrospinal fluid , Diffusion Tensor Imaging , Biomarkers/cerebrospinal fluid , Atrophy/pathology , Aged, 80 and over
18.
Alzheimers Dement ; 2024 Aug 11.
Article in English | MEDLINE | ID: mdl-39129223

ABSTRACT

INTRODUCTION: The heritability of Alzheimer's disease (AD) is estimated to be 58%-79%. However, known genes can only partially explain the heritability. METHODS: Here, we conducted gene-based exome-wide association study (ExWAS) of rare variants and single-variant ExWAS of common variants, utilizing data of 54,569 clinically diagnosed/proxy AD and related dementia (ADRD) and 295,421 controls from the UK Biobank. RESULTS: Gene-based ExWAS identified 11 genes predicting a higher ADRD risk, including five novel ones, namely FRMD8, DDX1, DNMT3L, MORC1, and TGM2, along with six previously reported ones, SORL1, GRN, PSEN1, ABCA7, GBA, and ADAM10. Single-variant ExWAS identified two ADRD-associated novel genes, SLCO1C1 and NDNF. The identified genes were predominantly enriched in amyloid-ß process pathways, microglia, and brain regions like hippocampus. The druggability evidence suggests that DDX1, DNMT3L, TGM2, SLCO1C1, and NDNF could be effective drug targets. DISCUSSION: Our study contributes to the current body of evidence on the genetic etiology of ADRD. HIGHLIGHTS: Gene-based analyses of rare variants identified five novel genes for Alzheimer's disease and related dementia (ADRD), including FRMD8, DDX1, DNMT3L, MORC1, and TGM2. Single-variant analyses of common variants identified two novel genes for ADRD, including SLCO1C1 and NDNF. The identified genes were predominantly enriched in amyloid-ß process pathways, microglia, and brain regions like hippocampus. DDX1, DNMT3L, TGM2, SLCO1C1, and NDNF could be effective drug targets.

19.
Alzheimers Dement ; 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39023044

ABSTRACT

INTRODUCTION: Alzheimer's disease (AD) is a devastating neurological disease with complex genetic etiology. Yet most known loci have only identified from the late-onset type AD in populations of European ancestry. METHODS: We performed a two-stage genome-wide association study (GWAS) of AD totaling 6878 Chinese and 63,926 European individuals. RESULTS: In addition to the apolipoprotein E (APOE) locus, our GWAS of two independent Chinese samples uncovered three novel AD susceptibility loci (KIAA2013, SLC52A3, and TCN2) and a novel ancestry-specific variant within EGFR (rs1815157). More replicated variants were observed in the Chinese (31%) than in the European samples (15%). In combining genome-wide associations and functional annotations, EGFR and TCN2 were prioritized as two of the most biologically significant genes. Phenome-wide Mendelian randomization suggests that high mean corpuscular hemoglobin concentration might protect against AD. DISCUSSION: The current study reveals novel AD susceptibility loci, emphasizes the importance of diverse populations in AD genetic research, and advances our understanding of disease etiology. HIGHLIGHTS: Loci KIAA2013, SLC52A3, and TCN2 were associated with Alzheimer's disease (AD) in Chinese populations. rs1815157 within the EGFR locus was associated with AD in Chinese populations. The genetic architecture of AD varied between Chinese and European populations. EGFR and TCN2 were prioritized as two of the most biologically significant genes. High mean corpuscular hemoglobin concentrations might have protective effects against AD.

20.
Alzheimers Dement ; 20(4): 2516-2525, 2024 04.
Article in English | MEDLINE | ID: mdl-38329281

ABSTRACT

INTRODUCTION: The objective of this study is to investigate the incremental value of amyloid positron emission tomography (Aß-PET) in a tertiary memory clinic setting in China. METHODS: A total of 1073 patients were offered Aß-PET using 18F-florbetapir. The neurologists determined a suspected etiology (Alzheimer's disease [AD] or non-AD) with a percentage estimate of their confidence and medication prescription both before and after receiving the Aß-PET results. RESULTS: After disclosure of the Aß-PET results, etiological diagnoses changed in 19.3% of patients, and diagnostic confidence increased from 69.3% to 85.6%. Amyloid PET results led to a change of treatment plan in 36.5% of patients. Compared to the late-onset group, the early-onset group had a more frequent change in diagnoses and a higher increase in diagnostic confidence. DISCUSSION: Aß-PET has significant impacts on the changes of diagnoses and management in Chinese population. Early-onset cases are more likely to benefit from Aß-PET than late-onset cases. HIGHLIGHTS: Amyloid PET contributes to diagnostic changes and its confidence in Chinese patients. Amyloid PET leads to a change of treatment plans in Chinese patients. Early-onset cases are more likely to benefit from amyloid PET than late-onset cases.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Humans , Amyloid , Alzheimer Disease/diagnostic imaging , Positron-Emission Tomography/methods , Amyloidogenic Proteins , Aniline Compounds , China , Amyloid beta-Peptides , Cognitive Dysfunction/diagnosis
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