Systems Biology

<em>Pseudomonas aeruginosa</em> Activates Quorum Sensing, Antioxidant Enzymes and Type VI Secretion in Response to Oxidative Stress to Initiate Biofilm Formation and Wound Chronicity

Thu, 2024-06-27 06:00

Antioxidants (Basel). 2024 May 27;13(6):655. doi: 10.3390/antiox13060655.

ABSTRACT

Pseudomonas aeruginosa (PA) is an opportunistic pathogen frequently isolated from cutaneous chronic wounds. How PA, in the presence of oxidative stress (OS), colonizes chronic wounds and forms a biofilm is still unknown. The purpose of this study is to investigate the changes in gene expression seen when PA is challenged with the high levels of OS present in chronic wounds. We used a biofilm-forming PA strain isolated from the chronic wounds of our murine model (RPA) and performed a qPCR to obtain gene expression patterns as RPA developed a biofilm in vitro in the presence of high levels of OS, and then compared the findings in vivo, in our mouse model of chronic wounds. We found that the planktonic bacteria under OS conditions overexpressed quorum sensing genes that are important for the bacteria to communicate with each other, antioxidant stress genes important to reduce OS in the microenvironment for survival, biofilm formation genes and virulence genes. Additionally, we performed RNAseq in vivo and identified the activation of novel genes/pathways of the Type VI Secretion System (T6SS) involved in RPA pathogenicity. In conclusion, RPA appears to survive the high OS microenvironment in chronic wounds and colonizes these wounds by turning on virulence, biofilm-forming and survival genes. These findings reveal pathways that may be promising targets for new therapies aimed at disrupting PA-containing biofilms immediately after debridement to facilitate the treatment of chronic human wounds.

PMID:38929094 | DOI:10.3390/antiox13060655

Categories: Literature Watch

Beyond the Usual Suspects: Examining the Role of Understudied Histone Variants in Breast Cancer

Thu, 2024-06-27 06:00

Int J Mol Sci. 2024 Jun 20;25(12):6788. doi: 10.3390/ijms25126788.

ABSTRACT

The incorporation of histone variants has structural ramifications on nucleosome dynamics and stability. Due to their unique sequences, histone variants can alter histone-histone or histone-DNA interactions, impacting the folding of DNA around the histone octamer and the overall higher-order structure of chromatin fibers. These structural modifications alter chromatin compaction and accessibility of DNA by transcription factors and other regulatory proteins to influence gene regulatory processes such as DNA damage and repair, as well as transcriptional activation or repression. Histone variants can also generate a unique interactome composed of histone chaperones and chromatin remodeling complexes. Any of these perturbations can contribute to cellular plasticity and the progression of human diseases. Here, we focus on a frequently overlooked group of histone variants lying within the four human histone gene clusters and their contribution to breast cancer.

PMID:38928493 | DOI:10.3390/ijms25126788

Categories: Literature Watch

An Efficient Method for Vault Nanoparticle Conjugation with Finely Adjustable Amounts of Antibodies and Small Molecules

Thu, 2024-06-27 06:00

Int J Mol Sci. 2024 Jun 16;25(12):6629. doi: 10.3390/ijms25126629.

ABSTRACT

Vaults are eukaryotic ribonucleoproteins consisting of 78 copies of the major vault protein (MVP), which assemble into a nanoparticle with an about 60 nm volume-based size, enclosing other proteins and RNAs. Regardless of their physiological role(s), vaults represent ideal, natural hollow nanoparticles, which are produced by the assembly of the sole MVP. Here, we have expressed in Komagataella phaffi and purified an MVP variant carrying a C-terminal Z peptide (vault-Z), which can tightly bind an antibody's Fc portion, in view of targeted delivery. Via surface plasmon resonance analysis, we could determine a 2.5 nM affinity to the monoclonal antibody Trastuzumab (Tz)/vault-Z 1:1 interaction. Then, we characterized the in-solution interaction via co-incubation, ultracentrifugation, and analysis of the pelleted proteins. This showed virtually irreversible binding up to an at least 10:1 Tz/vault-Z ratio. As a proof of concept, we labeled the Fc portion of Tz with a fluorophore and conjugated it with the nanoparticle, along with either Tz or Cetuximab, another monoclonal antibody. Thus, we could demonstrate antibody-dependent, selective uptake by the SKBR3 and MDA-MB 231 breast cancer cell lines. These investigations provide a novel, flexible technological platform that significantly extends vault-Z's applications, in that it can be stably conjugated with finely adjusted amounts of antibodies as well as of other molecules, such as fluorophores, cell-targeting peptides, or drugs, using the Fc portion as a scaffold.

PMID:38928334 | DOI:10.3390/ijms25126629

Categories: Literature Watch

The Difference in Serum Metabolomic Profiles between the Good and Poor Outcome Groups at 3 Months in the Early and Late Phases of Aneurysmal Subarachnoid Hemorrhage

Thu, 2024-06-27 06:00

Int J Mol Sci. 2024 Jun 15;25(12):6597. doi: 10.3390/ijms25126597.

ABSTRACT

We aimed to investigate the characteristics of serum metabolomics in aneurysmal subarachnoid hemorrhage patients (aSAH) with different 3-month outcomes (good = modified Rankin score: 0-3 vs. poor = mRS 4-6). We collected serum samples from 46 aSAH patients at 24 (D1) and 168 (D7) hours after injury for analysis by liquid chromatography-mass spectrometry. Ninety-six different metabolites were identified. Groups were compared using multivariate (orthogonal partial least squares discriminant analysis), univariate, and receiving operator characteristic (ROC) methods. We observed a marked decrease in serum homocysteine levels at the late phase (D7) compared to the early phase (D1). At both D1 and D7, mannose and sorbose levels were notably higher, alongside elevated levels of kynurenine (D1) and increased 2-hydroxybutyrate, methyl-galactoside, creatine, xanthosine, p-hydroxyphenylacetate, N-acetylalanine, and N-acetylmethionine (all D7) in the poor outcome group. Conversely, levels of guanidinoacetate (D7) and several amino acids (both D1 and D7) were significantly lower in patients with poor outcomes. Our results indicate significant changes in energy metabolism, shifting towards ketosis and alternative energy sources, both in the early and late phases, even with adequate enteral nutrition, particularly in patients with poor outcomes. The early activation of the kynurenine pathway may also play a role in this process.

PMID:38928303 | DOI:10.3390/ijms25126597

Categories: Literature Watch

Advances in Molecular Plant Sciences

Thu, 2024-06-27 06:00

Int J Mol Sci. 2024 Jun 10;25(12):6408. doi: 10.3390/ijms25126408.

ABSTRACT

In recent years, as biotechnological advancements have continued to unfold, our understanding of plant molecular biology has undergone a remarkable transformation [...].

PMID:38928115 | DOI:10.3390/ijms25126408

Categories: Literature Watch

Genetic Analysis of the Plasmid-Based Temperature-Lethal Mutant <em>pa1792|lpxH(Ts)</em> in <em>Pseudomonas aeruginosa</em>

Thu, 2024-06-27 06:00

Genes (Basel). 2024 Jun 14;15(6):784. doi: 10.3390/genes15060784.

ABSTRACT

Many enzymes in the Raetz pathway for lipid A biosynthesis in Escherichia coli are essential. A homologous protein Pa1792|LpxH in Pseudomonas aeruginosa is known to complement the loss of LpxH in E. coli. Genome-wide transposon-insertion sequencing analysis indicates that lpxH is essential in P. aeruginosa. However, genetic analysis of lpxH in P. aeruginosa has not been carried out, partly because the conditional alleles of essential genes are not readily constructed. In this study, we first constructed a plasmid-based temperature-sensitive mutant ΔlpxH/pTS-lpxH or lpxH(Ts) in P. aeruginosa PAO1. Spot-plating assay indicated that lpxH(Ts) was lethal at a restrictive temperature, confirming its essentiality for growth. Microscopic analysis revealed that lpxH(Ts) exhibited an oval-shaped morphology, suggesting that lpxH was required for rod-shape formation. SDS-PAGE and Western blotting analysis showed that lpxH(Ts) failed to synthesize lipid A, consistent with its function in lipid A biosynthesis. Strong expression of lpxH but not the non-homologous isoenzyme lpxI or lpxG impeded growth and caused cell lysis, implying that lpxH-specific cofactors were required for this toxic effect in P. aeruginosa. Together, our results demonstrate that lpxH is essential for lipid A biosynthesis, rod-shaped growth, and viability in P. aeruginosa. We propose that this plasmid-based conditional allele is a useful tool for the genetic study of essential genes in P. aeruginosa.

PMID:38927720 | DOI:10.3390/genes15060784

Categories: Literature Watch

Comparative Analysis of Shapley Values Enhances Transcriptomics Insights across Some Common Uterine Pathologies

Thu, 2024-06-27 06:00

Genes (Basel). 2024 Jun 1;15(6):723. doi: 10.3390/genes15060723.

ABSTRACT

Uterine pathologies pose a challenge to women's health on a global scale. Despite extensive research, the causes and origin of some of these common disorders are not well defined yet. This study presents a comprehensive analysis of transcriptome data from diverse datasets encompassing relevant uterine pathologies such as endometriosis, endometrial cancer and uterine leiomyomas. Leveraging the Comparative Analysis of Shapley values (CASh) technique, we demonstrate its efficacy in improving the outcomes of the classical differential expression analysis on transcriptomic data derived from microarray experiments. CASh integrates the microarray game algorithm with Bootstrap resampling, offering a robust statistical framework to mitigate the impact of potential outliers in the expression data. Our findings unveil novel insights into the molecular signatures underlying these gynecological disorders, highlighting CASh as a valuable tool for enhancing the precision of transcriptomics analyses in complex biological contexts. This research contributes to a deeper understanding of gene expression patterns and potential biomarkers associated with these pathologies, offering implications for future diagnostic and therapeutic strategies.

PMID:38927658 | DOI:10.3390/genes15060723

Categories: Literature Watch

The Advancement and Application of the Single-Cell Transcriptome in Biological and Medical Research

Thu, 2024-06-27 06:00

Biology (Basel). 2024 Jun 19;13(6):451. doi: 10.3390/biology13060451.

ABSTRACT

Single-cell RNA sequencing technology (scRNA-seq) has been steadily developing since its inception in 2009. Unlike bulk RNA-seq, scRNA-seq identifies the heterogeneity of tissue cells and reveals gene expression changes in individual cells at the microscopic level. Here, we review the development of scRNA-seq, which has gone through iterations of reverse transcription, in vitro transcription, smart-seq, drop-seq, 10 × Genomics, and spatial single-cell transcriptome technologies. The technology of 10 × Genomics has been widely applied in medicine and biology, producing rich research results. Furthermore, this review presents a summary of the analytical process for single-cell transcriptome data and its integration with other omics analyses, including genomes, epigenomes, proteomes, and metabolomics. The single-cell transcriptome has a wide range of applications in biology and medicine. This review analyzes the applications of scRNA-seq in cancer, stem cell research, developmental biology, microbiology, and other fields. In essence, scRNA-seq provides a means of elucidating gene expression patterns in single cells, thereby offering a valuable tool for scientific research. Nevertheless, the current single-cell transcriptome technology is still imperfect, and this review identifies its shortcomings and anticipates future developments. The objective of this review is to facilitate a deeper comprehension of scRNA-seq technology and its applications in biological and medical research, as well as to identify avenues for its future development in alignment with practical needs.

PMID:38927331 | DOI:10.3390/biology13060451

Categories: Literature Watch

The cacao gene atlas: a transcriptome developmental atlas reveals highly tissue-specific and dynamically-regulated gene networks in Theobroma cacao L

Wed, 2024-06-26 06:00

BMC Plant Biol. 2024 Jun 26;24(1):601. doi: 10.1186/s12870-024-05171-9.

ABSTRACT

BACKGROUND: Theobroma cacao, the cocoa tree, is a tropical crop grown for its highly valuable cocoa solids and fat which are the basis of a 200-billion-dollar annual chocolate industry. However, the long generation time and difficulties associated with breeding a tropical tree crop have limited the progress of breeders to develop high-yielding disease-resistant varieties. Development of marker-assisted breeding methods for cacao requires discovery of genomic regions and specific alleles of genes encoding important traits of interest. To accelerate gene discovery, we developed a gene atlas composed of a large dataset of replicated transcriptomes with the long-term goal of progressing breeding towards developing high-yielding elite varieties of cacao.

RESULTS: We describe the creation of the Cacao Transcriptome Atlas, its global characterization and define sets of genes co-regulated in highly organ- and temporally-specific manners. RNAs were extracted and transcriptomes sequenced from 123 different tissues and stages of development representing major organs and developmental stages of the cacao lifecycle. In addition, several experimental treatments and time courses were performed to measure gene expression in tissues responding to biotic and abiotic stressors. Samples were collected in replicates (3-5) to enable statistical analysis of gene expression levels for a total of 390 transcriptomes. To promote wide use of these data, all raw sequencing data, expression read mapping matrices, scripts, and other information used to create the resource are freely available online. We verified our atlas by analyzing the expression of genes with known functions and expression patterns in Arabidopsis (ACT7, LEA19, AGL16, TIP13, LHY, MYB2) and found their expression profiles to be generally similar between both species. We also successfully identified tissue-specific genes at two thresholds in many tissue types represented and a set of genes highly conserved across all tissues.

CONCLUSION: The Cacao Gene Atlas consists of a gene expression browser with graphical user interface and open access to raw sequencing data files as well as the unnormalized and CPM normalized read count data mapped to several cacao genomes. The gene atlas is a publicly available resource to allow rapid mining of cacao gene expression profiles. We hope this resource will be used to help accelerate the discovery of important genes for key cacao traits such as disease resistance and contribute to the breeding of elite varieties to help farmers increase yields.

PMID:38926852 | DOI:10.1186/s12870-024-05171-9

Categories: Literature Watch

Exploring molecular targets: herbal isolates in cervical cancer therapy

Wed, 2024-06-26 06:00

Genomics Inform. 2024 Jun 26;22(1):9. doi: 10.1186/s44342-024-00008-1.

ABSTRACT

OBJECTIVE: Cervical cancer (CxCa) stands as a significant global health challenge, ranking fourth in cancer-related mortality among the female population. While chemotherapy regimens have demonstrated incremental progress in extending overall survival, the outlook for recurrent CxCa patients remains disheartening. An imperative necessity arises to delve into innovative therapeutic avenues, with molecular targeted therapy emerging as a promising candidate. Previous investigations have shed light on the therapeutic effectiveness of five distinct herbal compounds, epicatechin, curcumin, myricetin, jatrorrhizine, and arborinine, within the context of CxCa.

METHODS: A systems biology approach was employed to discern differentially expressed genes (DEGs) in CxCa tissues relative to healthy cervical epithelial tissues. A protein-protein interaction network (PPIN) was constructed, anchored in the genes related to CxCa. The central genes were discerned within the PPIN, and Kaplan-Meier survival curves explored their prognostic significance. An assessment of the binding affinity of the selected herbal compounds to the master regulator of prognostic markers in CxCa was conducted.

RESULTS: A significant correlation between the overexpression of MYC, IL6, JUN, RRM2, and VEGFA and an adverse prognosis in CxCa was indicated. The regulation of these markers is notably influenced by the transcription factor CEBPD. Molecular docking analysis indicated that the binding affinity between myricetin and the CEBPD DNA binding site was robust.

CONCLUSION: The findings presented herein have unveiled pivotal genes and pathways that play a central role in the malignant transformation of CxCa. CEBPD has emerged as a potential target for harnessing the therapeutic potential of myricetin in this context.

PMID:38926832 | DOI:10.1186/s44342-024-00008-1

Categories: Literature Watch

An intermediate Rb-E2F activity state safeguards proliferation commitment

Wed, 2024-06-26 06:00

Nature. 2024 Jun 26. doi: 10.1038/s41586-024-07554-2. Online ahead of print.

ABSTRACT

Tissue repair, immune defence and cancer progression rely on a vital cellular decision between quiescence and proliferation1,2. Mammalian cells proliferate by triggering a positive feedback mechanism3,4. The transcription factor E2F activates cyclin-dependent kinase 2 (CDK2), which in turn phosphorylates and inactivates the E2F inhibitor protein retinoblastoma (Rb). This action further increases E2F activity to express genes needed for proliferation. Given that positive feedback can inadvertently amplify small signals, understanding how cells keep this positive feedback in check remains a puzzle. Here we measured E2F and CDK2 signal changes in single cells and found that the positive feedback mechanism engages only late in G1 phase. Cells spend variable and often extended times in a reversible state of intermediate E2F activity before committing to proliferate. This intermediate E2F activity is proportional to the amount of phosphorylation of a conserved T373 residue in Rb that is mediated by CDK2 or CDK4/CDK6. Such T373-phosphorylated Rb remains bound on chromatin but dissociates from it once Rb is hyperphosphorylated at many sites, which fully activates E2F. The preferential initial phosphorylation of T373 can be explained by its relatively slower rate of dephosphorylation. Together, our study identifies a primed state of intermediate E2F activation whereby cells sense external and internal signals and decide whether to reverse and exit to quiescence or trigger the positive feedback mechanism that initiates cell proliferation.

PMID:38926571 | DOI:10.1038/s41586-024-07554-2

Categories: Literature Watch

MOI is a comprehensive database collecting processed multi-omics data associated with viral infection

Wed, 2024-06-26 06:00

Sci Rep. 2024 Jun 26;14(1):14725. doi: 10.1038/s41598-024-65629-6.

ABSTRACT

Viral infections pose significant public health challenges, exemplified by the global impact of COVID-19 caused by SARS-CoV-2. Understanding the intricate molecular mechanisms governing virus-host interactions is pivotal for effective intervention strategies. Despite the burgeoning multi-omics data on viral infections, a centralized database elucidating host responses to viruses remains lacking. In response, we have developed a comprehensive database named 'MOI' (available at http://www.fynn-guo.cn/ ), specifically designed to aggregate processed Multi-Omics data related to viral Infections. This meticulously curated database serves as a valuable resource for conducting detailed investigations into virus-host interactions. Leveraging high-throughput sequencing data and metadata from PubMed and Gene Expression Omnibus (GEO), MOI comprises over 3200 viral-infected samples, encompassing human and murine infections. Standardized processing pipelines ensure data integrity, including bulk RNA sequencing (RNA-seq), single-cell RNA-seq (scRNA-seq), Chromatin Immunoprecipitation sequencing (ChIP-seq), and Assay for Transposase-Accessible Chromatin using sequencing (ATAC-seq). MOI offers user-friendly interfaces presenting comprehensive cell marker tables, gene expression data, and epigenetic landscape charts. Analytical tools for DNA sequence conversion, FPKM calculation, differential gene expression, and Gene Ontology (GO)/ Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment enhance data interpretation. Additionally, MOI provides 16 visualization plots for intuitive data exploration. In summary, MOI serves as a valuable repository for researchers investigating virus-host interactions. By centralizing and facilitating access to multi-omics data, MOI aims to advance our understanding of viral pathogenesis and expedite the development of therapeutic interventions.

PMID:38926513 | DOI:10.1038/s41598-024-65629-6

Categories: Literature Watch

Associations of genetically predicted vitamin D status and deficiency with the risk of carotid artery plaque: a Mendelian randomization study

Wed, 2024-06-26 06:00

Sci Rep. 2024 Jun 26;14(1):14743. doi: 10.1038/s41598-024-64731-z.

ABSTRACT

Low concentrations of circulating 25-hydroxy-vitamin D are observationally associated with an increased risk of subclinical atherosclerosis and cardiovascular disease. However, randomized controlled trials have not reported the beneficial effects of vitamin D supplementation on atherosclerotic cardiovascular disease (ASCVD) outcomes. Whether genetically predicted vitamin D status confers protection against the development of carotid artery plaque, a powerful predictor of subclinical atherosclerosis, remains unknown. We conducted a two-sample Mendelian randomization (MR) study to explore the association of genetically predicted vitamin D status and deficiency with the risk of developing carotid artery plaque. We leveraged three genome-wide association studies (GWAS) of vitamin D status and one GWAS of vitamin D deficiency. We used the inverse-variance weighted (IVW) approach as our main method, and MR-Egger, weighted-median, and radialMR as MR sensitivity analyses. We also conducted sensitivity analyses using biologically plausible genetic instruments located within genes encoding for vitamin D metabolism (GC, CYP2R1, DHCR7, CYP24A1). We did not find significant associations between genetically predicted vitamin D status (Odds ratio (OR) = 0.99, P = 0.91) and deficiency (OR = 1.00, P = 0.97) with the risk of carotid artery plaque. We additionally explored the potential causal effect of vitamin D status on coronary artery calcification (CAC) and carotid intima-media thickness (cIMT), two additional markers of subclinical atherosclerosis, and we did not find any significant association (βCAC = - 0.14, P = 0.23; βcIMT = 0.005, P = 0.19). These findings did not support the causal effects of vitamin D status and deficiency on the risk of developing subclinical atherosclerosis.

PMID:38926411 | DOI:10.1038/s41598-024-64731-z

Categories: Literature Watch

Metabotropic signaling within somatostatin interneurons controls transient thalamocortical inputs during development

Wed, 2024-06-26 06:00

Nat Commun. 2024 Jun 26;15(1):5421. doi: 10.1038/s41467-024-49732-w.

ABSTRACT

During brain development, neural circuits undergo major activity-dependent restructuring. Circuit wiring mainly occurs through synaptic strengthening following the Hebbian "fire together, wire together" precept. However, select connections, essential for circuit development, are transient. They are effectively connected early in development, but strongly diminish during maturation. The mechanisms by which transient connectivity recedes are unknown. To investigate this process, we characterize transient thalamocortical inputs, which depress onto somatostatin inhibitory interneurons during development, by employing optogenetics, chemogenetics, transcriptomics and CRISPR-based strategies in mice. We demonstrate that in contrast to typical activity-dependent mechanisms, transient thalamocortical connectivity onto somatostatin interneurons is non-canonical and involves metabotropic signaling. Specifically, metabotropic-mediated transcription, of guidance molecules in particular, supports the elimination of this connectivity. Remarkably, we found that this process impacts the development of normal exploratory behaviors of adult mice.

PMID:38926335 | DOI:10.1038/s41467-024-49732-w

Categories: Literature Watch

Transient Co-expression of Membrane Protein Complexes in Mammalian Cells

Wed, 2024-06-26 06:00

Methods Mol Biol. 2024;2810:11-28. doi: 10.1007/978-1-0716-3878-1_2.

ABSTRACT

Membrane proteins are essential components of biological membranes with key roles in cellular processes such as nutrient transport, cell communication, signaling, or energy conversion. Due to their crucial functions, membrane proteins and their complexes are often targets for therapeutic interventions. Expression and purification of membrane proteins are often a bottleneck to yield sufficient material for structural studies and further downstream characterization. Taking advantage of the Expi293 expression system for the production of eukaryotic proteins, we present a very efficient and fast protocol for the co-expression of a membrane complex. Here, we use transient transfection to co-express the membrane transporter PHT1 with its adaptor protein TASL. To allow the simultaneous screening of different proteins, constructs, or interaction partners, we make use of the Twin-Strep magnetic system. The protocol can be applied for small-scale screening of any membrane protein alone or co-expressed with interacting partners followed by large-scale production and purification of a potential membrane protein complex.

PMID:38926270 | DOI:10.1007/978-1-0716-3878-1_2

Categories: Literature Watch

Omeprazole Induces CYP3A4 mRNA Expression but Not CYP3A4 Protein Expression in HepaRG Cells

Wed, 2024-06-26 06:00

Biol Pharm Bull. 2024;47(6):1218-1223. doi: 10.1248/bpb.b24-00161.

ABSTRACT

Unknown interactions between drugs remain the limiting factor for clinical application of drugs, and the induction and inhibition of drug-metabolizing CYP enzymes are considered the key to examining the drug-drug interaction (DDI). In this study, using human HepaRG cells as an in vitro model system, we analyzed the potential DDI based on the expression levels of CYP3A4 and CYP1A2. Rifampicin and omeprazole, the potent inducers for CYP3A4 and CYP1A2, respectively, induce expression of the corresponding CYP enzymes at both the mRNA and protein levels. We noticed that, in addition to inducing CYP1A2, omeprazole induced CYP3A4 mRNA expression in HepaRG cells. However, unexpectedly, CYP3A4 protein expression levels were not increased after omeprazole treatment. Concurrent administration of rifampicin and omeprazole showed an inhibitory effect of omeprazole on the CYP3A4 protein expression induced by rifampicin, while its mRNA induction remained intact. Cycloheximide chase assay revealed increased CYP3A4 protein degradation in the cells exposed to omeprazole. The data presented here suggest the potential importance of broadening the current DDI examination beyond conventional transcriptional induction and enzyme-activity inhibition tests to include post-translational regulation analysis of CYP enzyme expression.

PMID:38925922 | DOI:10.1248/bpb.b24-00161

Categories: Literature Watch

Isochrony as ancestral condition to call and song in a primate

Wed, 2024-06-26 06:00

Ann N Y Acad Sci. 2024 Jun 25. doi: 10.1111/nyas.15151. Online ahead of print.

ABSTRACT

Animal songs differ from calls in function and structure, and have comparative and translational value, showing similarities to human music. Rhythm in music is often distributed in quantized classes of intervals known as rhythmic categories. These classes have been found in the songs of a few nonhuman species but never in their calls. Are rhythmic categories song-specific, as in human music, or can they transcend the song-call boundary? We analyze the vocal displays of one of the few mammals producing both songs and call sequences: Indri indri. We test whether rhythmic categories (a) are conserved across songs produced in different contexts, (b) exist in call sequences, and (c) differ between songs and call sequences. We show that rhythmic categories occur across vocal displays. Vocalization type and function modulate deployment of categories. We find isochrony (1:1 ratio, like the rhythm of a ticking clock) in all song types, but only advertisement songs show three rhythmic categories (1:1, 1:2, 2:1 ratios). Like songs, some call types are also isochronous. Isochrony is the backbone of most indri vocalizations, unlike human speech, where it is rare. In indri, isochrony underlies both songs and hierarchy-less call sequences and might be ancestral to both.

PMID:38925552 | DOI:10.1111/nyas.15151

Categories: Literature Watch

Multiplexed single-cell characterization of alternative polyadenylation regulators

Wed, 2024-06-26 06:00

Cell. 2024 Jun 20:S0092-8674(24)00645-7. doi: 10.1016/j.cell.2024.06.005. Online ahead of print.

ABSTRACT

Most mammalian genes have multiple polyA sites, representing a substantial source of transcript diversity regulated by the cleavage and polyadenylation (CPA) machinery. To better understand how these proteins govern polyA site choice, we introduce CPA-Perturb-seq, a multiplexed perturbation screen dataset of 42 CPA regulators with a 3' scRNA-seq readout that enables transcriptome-wide inference of polyA site usage. We develop a framework to detect perturbation-dependent changes in polyadenylation and characterize modules of co-regulated polyA sites. We find groups of intronic polyA sites regulated by distinct components of the nuclear RNA life cycle, including elongation, splicing, termination, and surveillance. We train and validate a deep neural network (APARENT-Perturb) for tandem polyA site usage, delineating a cis-regulatory code that predicts perturbation response and reveals interactions between regulatory complexes. Our work highlights the potential for multiplexed single-cell perturbation screens to further our understanding of post-transcriptional regulation.

PMID:38925112 | DOI:10.1016/j.cell.2024.06.005

Categories: Literature Watch

Improving Clinical Registry Data Quality via Linkage With Survival Data From State-Based Population Registries

Wed, 2024-06-26 06:00

JCO Clin Cancer Inform. 2024 Jun;8:e2400025. doi: 10.1200/CCI.24.00025.

ABSTRACT

PURPOSE: Real-world data (RWD) collected on patients treated as part of routine clinical care form the basis of cancer clinical registries. Capturing accurate death data can be challenging, with inaccurate survival data potentially compromising the integrity of registry-based research. Here, we explore the utility of data linkage (DL) to state-based registries to enhance the capture of survival outcomes.

METHODS: We identified consecutive adult patients with brain tumors treated in the state of Victoria from the Brain Tumour Registry Australia: Innovation and Translation (BRAIN) database, who had no recorded date of death and no follow-up within the last 6 months. Full name and date of birth were used to match patients in the BRAIN registry with those in the Victorian Births, Deaths and Marriages (BDM) registry. Overall survival (OS) outcomes were compared pre- and post-DL.

RESULTS: Of the 7,346 clinical registry patients, 5,462 (74%) had no date of death and no follow-up recorded within the last 6 months. Of the 5,462 patients, 1,588 (29%) were matched with a date of death in BDM. Factors associated with an increased number of matches were poor prognosis tumors, older age, and social disadvantage. OS was significantly overestimated pre-DL compared with post-DL for the entire cohort (pre- v post-DL: hazard ratio, 1.43; P < .001; median, 29.9 months v 16.7 months) and for most individual tumor types. This finding was present independent of the tumor prognosis.

CONCLUSION: As revealed by linkage with BDM, a high proportion of patients in a brain cancer clinical registry had missing death data, contributed to by informative censoring, inflating OS calculations. DL to pertinent registries on an ongoing basis should be considered to ensure accurate reporting of survival data and interpretation of RWD outcomes.

PMID:38924710 | DOI:10.1200/CCI.24.00025

Categories: Literature Watch

Developing and Investigating a Nanovibration Intervention for the Prevention/Reversal of Bone Loss Following Spinal Cord Injury

Wed, 2024-06-26 06:00

ACS Nano. 2024 Jun 26. doi: 10.1021/acsnano.4c02104. Online ahead of print.

ABSTRACT

Osteoporosis disrupts the fine-tuned balance between bone formation and resorption, leading to reductions in bone quantity and quality and ultimately increasing fracture risk. Prevention and treatment of osteoporotic fractures is essential for reductions in mortality, morbidity, and the economic burden, particularly considering the aging global population. Extreme bone loss that mimics time-accelerated osteoporosis develops in the paralyzed limbs following complete spinal cord injury (SCI). In vitro nanoscale vibration (1 kHz, 30 or 90 nm amplitude) has been shown to drive differentiation of mesenchymal stem cells toward osteoblast-like phenotypes, enhancing osteogenesis and inhibiting osteoclastogenesis simultaneously. Here, we develop and characterize a wearable device designed to deliver and monitor continuous nanoamplitude vibration to the hindlimb long bones of rats with complete SCI. We investigate whether a clinically feasible dose of nanovibration (two 2 h/day, 5 days/week for 6 weeks) is effective at reversing the established SCI-induced osteoporosis. Laser interferometry and finite element analysis confirmed transmission of nanovibration into the bone, and microcomputed tomography and serum bone formation and resorption markers assessed effectiveness. The intervention did not reverse SCI-induced osteoporosis. However, serum analysis indicated an elevated concentration of the bone formation marker procollagen type 1 N-terminal propeptide (P1NP) in rats receiving 40 nm amplitude nanovibration, suggesting increased synthesis of type 1 collagen, the major organic component of bone. Therefore, enhanced doses of nanovibrational stimulus may yet prove beneficial in attenuating/reversing osteoporosis, particularly in less severe forms of osteoporosis.

PMID:38924391 | DOI:10.1021/acsnano.4c02104

Categories: Literature Watch

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