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A sex-specific cytochrome P-450(F-1) colocalized with various neuropeptides in the paraventricular and supraoptic nuclei of female rats.

Numerous cells containing P-450(F-1) were detected in the magnocellular and parvocellular neurons of the paraventricular nucleus of the hypothalamus. Electron microscopic analysis of immunoreactive neurons has shown that P-450(F-1) immunoreactivity is present on the Golgi apparatus and rough endoplasmic reticulum. In the paraventricular nucleus, the P-450(F-1)-positive magnocellular neurons frequently contained oxytocin and some of them also contained CRF. Vasopressin was colocalized with P-450(F-1), but these neurons did not express CRF. In the supraoptic nucleus, P-450(F-1) was colocalized with oxytocin or CRF in single neurons, but not with vasopressin. No cells exhibiting the colocalization of both P-450(F-1) and somatostatin were observed in these nuclei. The results of the present study concerning colocalization of P-450 and peptides suggest that P-450(F-1) is involved in the hypothalamo-hypophyseal neuroendocrine function in the female rat.

Animals

Ultrastructural localization of neurotensin-like immunoreactivity within dense core vesicles in perikarya, but not terminals, colocalizing tyrosine hydroxylase in the rat ventral tegmental area.

Within the rat ventral tegmental area (VTA), the parabrachial pigmentosus and paranigral subdivisions are known to differ in their functional responses to injected neurotensin. These subdivisions also vary in their connections with other brain regions and in their number of neurotensin-containing perikarya as seen by light microscopy. In both subdivisions, there may be intracellular as well as synaptic relations between dopamine and neurotensin. Dopaminergic neurons are known to be physiologically activated by neurotensin (NT) and may also contain this peptide. To characterize further the cellular relationships in each subdivision, we examined the ultrastructural immunocytochemical localization of a rat antiserum against NT and a rabbit antiserum against the catecholamine-synthesizing enzyme tyrosine hydroxylase (TH) in single sections. The NT antiserum was raised against the entire peptide sequence. Immunoblots showed that the antiserum recognized the original antigen as well as the related peptides neuromedin N and lysine 8- arginine 9- neurotensin 10-13 (LANT-6). In both the parabrachial pigmentosus and paranigral subdivisions, neurotensin-like immunoreactivity (NTLI) was localized predominantly in the large (80-100 nm) dense core vesicles using the peroxidase anti-peroxidase (PAP) method. In tissue labeled for NT by the PAP method and for TH by immunoautoradiography, serial section analysis revealed that all perikarya containing NTLI (n = 19) were also TH-positive. Three times as many perikarya colocalized NTLI and TH in the parabrachial pigmentosus subdivision (n = 15) as in the paranigral subdivision (n = 4). Occasionally, a perikaryon containing TH and NTLI could be found in direct apposition to a TH-labeled perikaryon without glial separation. In contrast to perikarya and dendrites, terminals showing NTLI (38 in parabrachial pigmentosus, 29 in paranigral) lacked detectable TH labeling. Of the terminals containing NTLI whose synaptic junctions could be identified, 48% were symmetric and 10% were asymmetric. The targets of these terminals included perikarya and dendrites lacking detectable immunoreactivity (69% in parabrachial pigmentosus, 55% in paranigral), immunolabeled for TH (26% in parabrachial pigmentosus, 38% in paranigral) or containing both NTLI and TH (5% in parabrachial pigmentosus, 7% in paranigral). Single terminals containing NTLI sometimes contacted more than one neuronal target, some of which were apposed to each other without glial separation. TH-labeled terminals synapsed onto double-labeled perikarya in the paranigral subdivision, but were not observed to do so in the parabrachial pigmentosus subdivision.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals

Microglial PICALM: A novel genetic driver and therapeutic target in vascular dementia.

BACKGROUND: Vascular dementia (VaD) lacks well-defined genetic mechanisms. Cell-type-specific effects of GWAS loci remain unexplored. METHODS: We integrated single&#x2011;cell eQTL data (183 donors, eight cell types) with VaD GWAS (3624 cases, 475,484 controls) using Mendelian randomization and Bayesian colocalization, replicated in an independent cohort (2074 cases, 456,366 controls). Subtype, snRNA&#x2011;seq, cell&#x2011;cell communication, PheWAS, expression profiling, and drug prediction with BBB permeability assessment were performed. RESULTS: Microglial PICALM was the only robustly replicated signal (OR = 0.8334, p = 5.3 &#xd7; 10&#x207b;&#x2074;; colocalization PP.H4 > 0.75). The effect was strongest in multiple infarctions dementia (OR = 0.7746). Exploratory snRNA-seq analysis (4 VaD vs. 4 controls; GSE282111) provided supporting evidence for microglial PICALM enrichment and downregulation (p < 0.001). PICALM&#x2011;high microglia showed enhanced neurovascular&#x2011; and phagocytosis&#x2011;related communication (e.g., SPP1, GAS6, GRN). PheWAS revealed no pleiotropy. In silico drug repurposing prioritised three FDA-approved BBB-penetrant compounds (disopyramide, benzocaine, amantadine) as candidates warranting further mechanistic validation. CONCLUSIONS: Microglial PICALM is identified as a likely genetic determinant of VaD, especially in the multiple infarctions subtype. Upregulating PICALM may be associated with a neuroprotective microglial phenotype, highlighting PICALM as a candidate therapeutic target warranting further experimental validation.

Humans

The H3K27me3 reader GmLHP1 impairs Phytophthora sojae resistance by repressing ethylene precursor accumulation in soybean.

Phytophthora root rot, caused by Phytophthora sojae, is a devastating soilborne disease of soybean (Glycine max). However, the epigenetic regulation of soybean responses to P. sojae remains incompletely understood. Here, using genetic, molecular and biochemical approaches, we characterized the functions of LIKE HETEROCHROMATIN PROTEIN 1 (GmLHP1) and its downstream regulatory network. We demonstrated that GmLHP1, as a reader of H3K27me3, negatively regulates soybean resistance to P. sojae. GmLHP1 binds to H3K27me3 peptides in vitro and colocalizes with H3K27me3 marks genome-wide in vivo. The integrated chromatin immunoprecipitation sequencing and RNA sequencing analysis identified the ethylene biosynthesis pathway gene 1-AMINO-CYCLOPROPANE-1-CARBOXYLATE SYNTHASE 18 (GmACS18) as being enriched for H3K27me3 and bound by GmLHP1, leading to its transcriptional downregulation. Notably, GmLHP1 associates with the GmACS18 promoter by directly binding to AATTAA motifs and recognizing H3K27me3 marks. Moreover, GmACS18 enhances defense against P. sojae by accumulating the ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC). Further analysis unveiled that recognition of H3K27me3 by GmLHP1 is essential for regulating soybean resistance to P. sojae through repressing GmACS18 transcription and decreasing ACC accumulation. Our findings reveal a novel epigenetic regulatory mechanism in which the H3K27me3 reader GmLHP1 blocks soybean resistance to P. sojae by repressing ethylene precursor ACC accumulation.

ACC accumulation

A multigene family that interacts with the amino terminus of plasmodium MSP-1 identified using the yeast two-hybrid system.

Merozoite surface protein 1 (MSP-1) is a high-molecular-weight protein expressed on the surface of the malaria merozoite in a noncovalent complex with other protein molecules. MSP-1 undergoes a series of proteolytic processing events, but no precise biological role for the various proteolytic fragments of MSP-1 or for the additional proteins present in the complex is known. Through the use of the yeast two-hybrid system, we have isolated genes encoding proteins that interact with a region of the amino-terminal proteolytic fragment of MSP-1 from the mouse parasite Plasmodium yoelii. This analysis has led to the isolation of two sequence-related molecules, one of which is the P. yoelii homologue of MSP-7 originally described in Plasmodium falciparum. BLAST analysis of the P. falciparum database has revealed that there are six related protein molecules present in this species encoded near each other on chromosome 13. In P. falciparum, we designated these molecules MSRP-1 to -5. Analysis of the P. yoelii database indicates a similar chromosomal organization for the two genes in the mouse parasite species. The three P. falciparum sequences with the highest degree of homology to the P. yoelii sequences isolated in the two-hybrid screen have been characterized at the molecular level (MSRP-1 to -3). Expression analysis indicated that the mRNAs are expressed at various levels in the different asexual stages. Immunofluorescence studies colocalized the expression of the MSRP molecules and the amino-terminal portion of MSP-1 to the surfaces of trophozoites. In vitro binding experiments confirmed the interaction between MSRP-1, MSRP-2, and the amino-terminal region of P. falciparum MSP-1.

Amino Acid Sequence

Druggable genome CRISPRi screen in hydrogels reveals regulators of cortactin-driven actin remodeling promoting glioblastoma invasion.

To identify therapeutic targets limiting glioblastoma invasion, we applied druggable genome CRISPRi screens and multiomic analysis to patient-derived glioblastoma cells in micro-dissectible biomimetic 3D hydrogels that permitted separation and analysis of core versus invasive fractions. Of 2,550 genes screened, 12 encoded druggable targets whose suppression limited invasion, of which AURKB (encoding aurora kinase B) and ACP1 (encoding low molecular weight protein tyrosine phosphatase, LMW-PTP) were validated in neurosphere assays and in vivo. Proximity labeling identified cortactin as a link between LMW-PTP and aurora B, and we observed that cortactin underwent serine phosphorylation by aurora B and tyrosine dephosphorylation by LMW-PTP. Targeting ACP1 or AURKB via CRISPRi or inhibitors in culture and in vivo shifted the cortactin phosphorylation balance in glioblastoma, reducing levels of cortactin and the actin-related protein 2/3 (Arp2/3) complex that mediates cortactin-induced actin stabilization, thereby reducing actin-cortactin-Arp2/3 colocalization and subsequent actin polymerization. AURKB or ACP1 targeting shifted actin from cytoplasm to the nucleus, reducing mesenchymal gene expression. Biophysical analysis implicated AURKB in glioblastoma cell adhesion and stiffness needed for initial migration and ACP1 in mechanical stress resistance required for later migration. These findings revealed a targetable axis balancing kinase and phosphatase activities to regulate actin polymerization during glioblastoma invasion.

Humans

Characterization and chemoproteomic profiling of protein O-GlcNAcylation in SOD1-G93A mouse model.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a devastating motor neuron disease. Protein O-linked &#x3b2;-N-acetylglucosamine (O-GlcNAc) modification has been found to affect the processing of several important proteins implicated in ALS. However, the overall level and cellular localization of O-GlcNAc during ALS progression are incompletely understood, and large-scale profiling of O-GlcNAcylation sites in this context remains unexplored. METHODS: By using immunostaining analysis and chemoenzymatic labeling-based quantitative chemoproteomics, we assayed O-GlcNAcylation dynamics of lumbar spinal cords from SOD-G93A mice and their non-transgenic (NTG) littermates, the most widely used animal model for studying ALS pathogenesis. RESULTS: We discovered that the global O-GlcNAcylation was significantly reduced at the disease end stage. Correlatively, a great increase of OGA was observed. Immunohistochemistry and immunofluorescence analysis showed a higher proportion of O-GlcNAc-positive neurons in the NTG group, while O-GlcNAc colocalization with astrocytes/microglia was elevated in SOD1-G93A mice. Moreover, we reported the identification of 568 high-confidence O-GlcNAc sites from end-stage SOD1-G93A and NTG mice. Of the 568 sites, 226-many of which occurred on neuronal function and structure-related proteins-were found to be dynamically regulated. CONCLUSION: These data provide a valuable resource for dissecting the functional role of O-GlcNAcylation in ALS and shed light on promising therapeutic avenues for ALS. The chemoenzymatic labeling-based chemoproteomic approach is applicable for probing O-GlcNAc dynamics in various pathological processes.

Animals

Integrative post-GWAS analysis prioritizes immune regulatory pathways and candidate effector signals in systemic lupus erythematosus.

BACKGROUND: Systemic lupus erythematosus (SLE) has a complex polygenic architecture, but translating genome-wide association signals into biologically interpretable candidates remains challenging. We applied an integrative post-GWAS framework to refine SLE-associated loci and prioritize candidate regulatory mechanisms. METHODS: European-ancestry SLE GWAS summary statistics from FinnGen and Bentham et al. were meta-analysed, comprising 8417 cases and 354,277 controls. After quality filtering, 6,782,131 SNPs were retained. Downstream analyses included LAVA regional prioritization, Bayesian colocalization with GTEx v8 whole-blood and spleen eQTLs, independent replication in the Juli&#xe0; et al. Spanish cohort, pathway enrichment, bivariate LAVA cross-trait local genetic correlation, and therapeutic annotation. RESULTS: The discovery meta-analysis identified 46 genome-wide significant SLE-associated loci, including putative novel signals requiring database/literature qualification. LAVA identified 14 candidate index variants across 12 high-confidence regions, of which nine index variants were retained as the primary prioritized set based on LAVA support and/or convergent regulatory evidence. The strongest association mapped to the chr6p21.3/MHC region (rs389884), where four genes showed colocalization support, including CLIC1 in whole blood and C4A in spleen. Because the chr6p21.3/MHC rs389884 region lead variant was unavailable for replication and no suitable proxy was identified, this signal was interpreted as an emerging candidate for functional validation rather than a replicated causal signal. Seven available variants replicated with concordant effects. An exploratory Roadmap immune chromatin-state overlap analysis placed 15 of 45 non-MHC lead variants (33.3%) directly, and 34 of 45 (75.6%) within &#xb1;10&#x202f;kb, in active immune enhancer/promoter states. Pathway analyses highlighted type I interferon, JAK-STAT signaling, cytokine regulation, and antigen presentation, while bivariate LAVA analyses supported shared local genetic architecture with rheumatoid arthritis, systemic sclerosis, and Sj&#xf6;gren syndrome. CONCLUSIONS: This integrative post-GWAS analysis refines SLE association signals into biologically interpretable candidate regions and supports interferon and JAK-STAT signaling as central genetically supported pathways in SLE.

CLIC1

Potential mitochondria-associated pathogenic genes in sepsis: a multi-omics Mendelian randomization study.

BACKGROUND: Mitochondrial dysfunction has been implicated in the pathophysiology of sepsis. However, human genetic evidence linking mitochondria-related genes to sepsis susceptibility remains limited. This study aimed to identify mitochondria-related genes associated with sepsis risk using a multi-omics Mendelian randomization framework. METHODS: Summary-data-based Mendelian randomization (SMR) was applied using sepsis genome-wide association study (GWAS) summary statistics from the UK Biobank and FinnGen databases. Expression, methylation, single-cell, and protein quantitative trait loci (QTLs) were used as genetic instruments. Colocalization analyses were conducted to evaluate whether SMR associations were driven by shared genetic variants. Expression of prioritized candidate genes was further examined in clinical septic samples, and correlations with disease severity (SOFA scores) were assessed. RESULTS: SMR analysis prioritized 13 mitochondria-related genes associated with sepsis risk. Immune cell-specific eQTL analysis suggested that genetically predicted SURF1 expression in memory B cells and na&#xef;ve T cells was associated with sepsis risk. Differential expression of 12 candidate genes was confirmed in septic patients by qPCR, and PPOX expression showed a negative correlation with SOFA scores. Integration of mQTL and eQTL data supported a regulatory relationship between methylation at cg06661924 and AK4 expression. Increased genetically predicted AK4 expression was associated with higher sepsis risk (OR&#xa0;=&#xa0;1.21, 95% CI 1.02-1.42). Protein-level analysis identified DUT as a potential sepsis-associated candidate, with consistent evidence across streptococcal and pneumococcal septicemia subtypes. Subtype analyses also suggested heterogeneous genetic signals across different sepsis subtypes. CONCLUSION: This study prioritized several mitochondria-related genes associated with sepsis susceptibility based on human genetic evidence. These findings provide candidate targets for further mechanistic and translational investigation.

Humans

Integrative Multi-Omics Mendelian Randomization Analysis Identifies NIT2 as a Potential Metabolic Risk Gene in Hepatocellular Carcinoma.

BACKGROUND: Metabolic pathways are crucial in hepatocellular carcinoma (HCC) pathogenesis, but causal metabolic genes remain unclear. This study used Summary data-based Mendelian Randomization (SMR) and colocalization to identify metabolism-related genetic loci influencing HCC risk. METHODS: Differentially expressed genes in hepatic malignancy phenotype versus normal tissues from TCGA and GTEx were analyzed. Metabolism-related candidates were examined via SMR and colocalization using multi-omics data: methylation (mQTL), expression (eQTL), and protein (pQTL) quantitative trait loci. RESULTS: Multi-omics integration identified NIT2 as a key metabolic regulator for HCC. The cg13016775 locus of NIT2 was associated with elevated HCC risk at gene (OR&#x2009;=&#x2009;1.618, 95% CI: 1.199-2.182) and protein (OR&#x2009;=&#x2009;4.432, 95% CI: 1.783-11.018) levels. Colocalization supported a shared causal variant (PPH4&#x2009;>&#x2009;0.6), linking NIT2 to hepatocarcinogenesis via metabolic regulation. CONCLUSIONS: This study provides multi-omics evidence for NIT2 as a potential causal gene in HCC, enhancing understanding of metabolic contributions to HCC pathogenesis and highlighting integrative genomics for uncovering causal relationships.

Carcinoma, Hepatocellular

Genetically Proxied Inhibition of Cholesterol-Lowering Drug Targets and Survival in HPV-Positive and Non-HPV-Driven Head and Neck Cancer: A Multicentre MR Study.

BACKGROUND: Cholesterol pathways may influence head and neck squamous cell carcinoma (HNSCC) progression, but evidence on prognosis is inconsistent. We used Mendelian randomization (MR) to test whether genetically proxied inhibition of major low-density lipoprotein cholesterol (LDL-C)-lowering drug targets and circulating lipid traits affects overall survival (OS) in HPV-positive and non-HPV-driven HNSCCs. METHODS: We proxied lifelong LDL-C lowering using 55 cis-acting single-nucleotide polymorphisms in HMGCR, NPC1L1, PCSK9, and LDL-receptor (LDLR) from the updated 2021 Global Lipids Genetics Consortium and instrumented circulating lipid traits. Two-sample MR estimated effects on OS in 4,869 multicentre HNSCC cases (1,291 HPV-positive; 3,578 non-HPV-driven) using minimally adjusted Cox models. Sensitivity analyses additionally adjusted for tumor stage and treatment, assessed collider bias using an external HNSCC incidence genome-wide association study, and examined between-center heterogeneity and colocalization. RESULTS: Using the updated Global Lipids Genetic Consortium 2021 instruments, genetically proxied HMGCR inhibition showed a directionally protective but nonsignificant association with OS in HPV-positive oropharyngeal HNSCC in the primary analysis [inverse variance weighted (IVW) HR = 0.19; 95% confidence interval (CI), 0.03-1.18; P = 0.08], with directionally concordant weighted median results. No corresponding protective association was observed for HMGCR in non-HPV-driven disease (IVW HR = 1.68; 95% CI, 0.78-3.63; P = 0.19). No clear evidence of association was observed for NPC1L1, PCSK9, LDLR, or circulating lipid traits in either HPV stratum. Colocalization did not support a shared causal variant. CONCLUSIONS: These analyses provide suggestive evidence that genetically proxied HMGCR inhibition may influence survival in HPV-positive oropharyngeal HNSCC. IMPACT: HMGCR-related pathways may be relevant to prognosis in HPV-positive oropharyngeal HNSCC, whereas clear survival effects of other cholesterol-lowering targets were not supported.

Humans

Nonradioactive in situ hybridisation of the translocation t(1;7) in myeloid malignancies.

Bone marrow cells of four patients with t(1;7) and myelodysplasia or acute myeloid leukemia were analyzed using nonradioactive in situ hydridisation. As probes, centromeric alphoid DNA sequences of chromosomes 1 and 7, a satellite DNA probe for 1q12, and chromosome-specific libraries of chromosomes 1 and 7 were used. The breakpoints of the t(1;7)(p11;p11) as determined by banding analysis could be studied more accurately, and the recently proposed designation t(1;7)(cen;cen) was confirmed in all four cases. Colocalization of alphoid DNA sequences of chromosomes 1 and 7 by double target in situ hybridisation was demonstrated in metaphase cells and also in interphase nuclei. The in situ hybridisation method described is applicable for the screening of peripheral blood cells or archival material.

Acute Disease

Panduratin A Induces Autophagy Through AMPK Activation Independent of mTOR Inhibition and Restricts Mycobacterium tuberculosis in Host Macrophages.

Tuberculosis (TB), caused by Mycobacterium tuberculosis (Mtb), remains a major global health burden, especially with the increasing prevalence of drug-resistant strains. There is an urgent need for new therapeutics that act via alternative mechanisms. Autophagy, a vital cell-autonomous defense process, allows macrophages to degrade intracellular pathogens such as Mtb and has gained attention as a potential target for host-directed therapy. In this study, we conducted a high-content imaging screen of herb-derived compounds to identify autophagy inducers in RAW264.7 macrophages. Panduratin A (NPA), a natural compound from Boesenbergia rotunda, was found to potently induce autophagy. NPA promoted autophagic vacuole formation in a dose-dependent fashion at low micromolar levels. Its autophagy-inducing effect was validated using RFP-GFP-LC3 dual fluorescence assays and immunoblotting in the presence of bafilomycin A1. Further mechanistic analysis revealed that NPA activates autophagy through AMPK activation, independent of mTOR inhibition. Importantly, NPA significantly promoted intracellular Mtb clearance and increased colocalization of Mtb with autophagosomes and lysosomes, in a manner dependent on Beclin-1. These findings highlight NPA as a potent enhancer of macrophage antimicrobial responses via autophagy, supporting its potential as a candidate for host-directed adjunctive therapy against TB.

Autophagy

Colocalization of adeno-associated virus Rep and capsid proteins in the nuclei of infected cells.

The mechanism of adeno-associated virus (AAV) DNA replication was characterized both genetically and biochemically. In this study, we used monoclonal and polyclonal antibodies to examine the AAV p5 (Rep78 and Rep68) and p19 (Rep52 and Rep40) proteins in infected cells. By overexpressing a truncated Rep78 protein in Escherichia coli, we obtained monoclonal antibody anti-78/68, which is specific for the p5 Rep proteins, and monoclonal antibody anti-52/40, which recognized both the p5 and p19 Rep proteins. In single-fluorochrome indirect immunofluorescence labeling experiments, the viral Rep proteins were localized in distinct intranuclear foci. Analysis of AAV proteins by double-fluorochrome indirect immunofluorescence experiments demonstrated that (i) all four AAV Rep proteins occupied the same intranuclear compartments and (ii) the Rep and capsid proteins colocalized in the nuclei of infected cells. These results suggest that replication centers similar to those established by other viruses exist for AAV. These reagents should provide a useful tool for further delineation of the mechanism of AAV replication in vitro.

Antibodies, Monoclonal

Identifying causal genetic variants for high-altitude adaptation through blood eQTL analysis in plateau populations.

A substantial number of genetic variants have been associated with high-altitude adaptation (HAA), yet most of them are located in non-coding genomic regions, leaving their specific functions and underlying mechanisms largely unknown. In this study, we analyze whole-genome and transcriptome sequencing data from a self-established cohort comprising 61 native highlanders (NHs) and 164 acclimatized newcomers (ANs), identifying 6,586 cis- and 34,203 trans-expression quantitative trait loci (eQTLs), along with 130 cell type-specific eQTLs. By further combining these data with a large East Asia (~30% Tibetan) genome-wide association study (GWAS) cohort, we employ colocalization and causal inference analyses to prioritize 85 cis-eQTLs associated with HAA and identify several novel candidate causal genes, including EXOC8, which is experimentally confirmed to regulate erythroid differentiation. Additionally, network analysis of these causal genes uncovers multiple regulatory pathways, mainly involving energy metabolism, autophagy, ubiquitination and inflammation. Our study offers a comprehensive eQTL map and reveals causal chains of "variant-gene-phenotype" for HAA-related traits, which provides new insights into potential regulatory mechanisms and targets for prevention and treatment of altitude sickness.

Quantitative Trait Loci

Genetic insights into the relationship between age at menarche and mental health-related phenotypes.

BACKGROUND: Multiple observational studies have reported associations between age at menarche (AAM) and mental health problems, yet their shared genetic architecture remains poorly characterized. METHODS: We leveraged genome-wide association study summary statistics for AAM and 15 mental health-related phenotypes. We conducted a multi-method integrative analysis encompassing linkage disequilibrium score regression, pleiotropic analysis under the composite null hypothesis, functional mapping and annotation, multi-marker analysis of genomic annotation, pathway enrichment, and bidirectional two-sample Mendelian randomization (MR) to explore shared genetic architecture and potential causal relationships. RESULTS: Our study identified significant genetic correlations between AAM and eight mental health-related phenotypes (miserableness, fed-up feelings, nervous feelings, ever thought that life is not worth living, ever self-harmed, depression, ever smoker, and age started smoking in former smokers). A total of 155 pleiotropic loci, 18 colocalized loci (e.g., 6q16.3), and 203 pleiotropic genes (e.g., LIN28B) were identified. These genes are expressed in multiple regions, including the cerebral cortex and hypothalamus, and are involved in various biological processes and signaling pathways. Additionally, MR analysis revealed causal associations between AAM and 5 mental health-related phenotypes (mood swings, miserableness, fed-up feelings, and age at which smokers started smoking in former/current smokers). CONCLUSIONS: Our study revealed extensive genetic associations between AAM and mental health-related phenotypes, and further explored the potential causal relationships between them. These findings enhance our understanding of the relationship from a genetic perspective and establish a foundation for future research to explore the biological pathways and environmental interactions contributing to these associations.

Genome-Wide Association Study

TP53 tumor suppressor gene: a model for investigating human mutagenesis.

More than 350 independent point mutations of the TP53 gene, found in a wide variety of human cancers, were compiled and analysed. From this study, we confirm the presence of four hot-spot regions which colocalize with some highly conserved domains of the protein. We also define a new hot-spot region which is observed predominantly in lung tumors. Analysis of the mutational events suggests the direct involvement of environmental carcinogens in lung tumors and hepatocarcinomas, and spontaneous mutagenesis generating essentially CpG transitions in most of the remaining ones. Furthermore, we demonstrate in this work that the TP53 gene is an informative model with which to study the molecular mechanisms of mutagenesis in the human genome.

Amino Acid Sequence

Multi-omic characterization of the Hispanic/Latino blood lipidome reveals an additional locus and attenuated genetic prediction.

While lipids have been extensively investigated, genetic regulation of the circulating lipidome in diverse populations remains poorly understood. We conducted a lipidome-wide genome-wide association study (GWAS) of 830 lipid species in 2,287 Hispanic/Latino participants and performed predictive modeling across omics layers. We identified 7,593 genome-wide significant SNPs mapping to 208 genes. Conditional analysis disentangled the long-range linkage disequilibrium artifacts from the pleiotropic FADS1/2/3 cluster. Separately, we discovered an association at the GPLD1 locus for a circulating ceramide. Colocalization revealed shared genetic architecture with conventional lipids alongside distinct, species-specific pathways. Incorporating Native/Indigenous American expression quantitative trait loci (eQTLs) within a multi-omic framework uncovered 62 likely regulatory genes missed by European-centric gene expression models. Finally, genetically regulated predictive models demonstrated performance declining from transcriptomics to proteomics to lipidomics, reflecting increased distance from gene action along the molecular cascade. Our study provides a genetic landscape of lipid metabolism in a highly burdened population and highlights the challenges in predicting lipid abundance.

Hispanic/Latino population