Systems Biology

Deep repertoire mining uncovers ultra-broad coronavirus neutralizing antibodies targeting multiple spike epitopes

Fri, 2024-06-07 06:00

Cell Rep. 2024 Jun 5;43(6):114307. doi: 10.1016/j.celrep.2024.114307. Online ahead of print.

ABSTRACT

The development of vaccines and therapeutics that are broadly effective against known and emergent coronaviruses is an urgent priority. We screened the circulating B cell repertoires of COVID-19 survivors and vaccinees to isolate over 9,000 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific monoclonal antibodies (mAbs), providing an expansive view of the SARS-CoV-2-specific Ab repertoire. Among the recovered antibodies was TXG-0078, an N-terminal domain (NTD)-specific neutralizing mAb that recognizes diverse alpha- and beta-coronaviruses. TXG-0078 achieves its exceptional binding breadth while utilizing the same VH1-24 variable gene signature and heavy-chain-dominant binding pattern seen in other NTD-supersite-specific neutralizing Abs with much narrower specificity. We also report CC24.2, a pan-sarbecovirus neutralizing antibody that targets a unique receptor-binding domain (RBD) epitope and shows similar neutralization potency against all tested SARS-CoV-2 variants, including BQ.1.1 and XBB.1.5. A cocktail of TXG-0078 and CC24.2 shows protection in vivo, suggesting their potential use in variant-resistant therapeutic Ab cocktails and as templates for pan-coronavirus vaccine design.

PMID:38848216 | DOI:10.1016/j.celrep.2024.114307

Categories: Literature Watch

CENsible: Interpretable Insights into Small-Molecule Binding with Context Explanation Networks

Fri, 2024-06-07 06:00

J Chem Inf Model. 2024 Jun 7. doi: 10.1021/acs.jcim.4c00825. Online ahead of print.

ABSTRACT

We present a novel and interpretable approach for assessing small-molecule binding using context explanation networks. Given the specific structure of a protein/ligand complex, our CENsible scoring function uses a deep convolutional neural network to predict the contributions of precalculated terms to the overall binding affinity. We show that CENsible can effectively distinguish active vs inactive compounds for many systems. Its primary benefit over related machine-learning scoring functions, however, is that it retains interpretability, allowing researchers to identify the contribution of each precalculated term to the final affinity prediction, with implications for subsequent lead optimization.

PMID:38847393 | DOI:10.1021/acs.jcim.4c00825

Categories: Literature Watch

Epidemic patterns of the different influenza virus types and subtypes/lineages for 10 years in Chongqing, China, 2010-2019

Fri, 2024-06-07 06:00

Hum Vaccin Immunother. 2024 Dec 31;20(1):2363076. doi: 10.1080/21645515.2024.2363076. Epub 2024 Jun 7.

ABSTRACT

To optimize seasonal influenza control and prevention programs in regions with potentially complicated seasonal patterns. Descriptive epidemiology was used to analyze the etiology of influenza, and chi-square tests were used to compare the epidemic patterns among different influenza virus types and subtypes/lineages. From January 2010 to December 2019, a total of 63,626 ILI cases were reported in Chongqing and 14,136 (22.22%) were laboratory-confirmed influenza cases. The proportions of specimens positive for influenza A and influenza B were 13.32% (8,478/63,626) and 8.86% (5,639/63,626), respectively. The proportion of positive specimens for influenza A reached the highest in winter (23.33%), while the proportion of positive specimens for influenza B reached the highest in spring (11.88%). Children aged 5-14 years old had the highest proportion of positive specimens for influenza. The influenza virus types/subtypes positive was significantly different by seasons and age groups (P<.001), but not by gender (p = .436). The vaccine strains were matched to the circulating influenza virus strains in all other years except for 2018 (vaccine strain was B/Colorado/06/2017; circulating strain was B/Yamagata). The study showed significant variations in epidemic patterns, including seasonal epidemic period and age distributions, among different influenza types, subtypes/lineages in Chongqing. Influenza vaccines matched to the circulating influenza virus strain in nine of the ten years. To prevent and mitigate the influenza outbreaks in this area, high risk population, especially children aged 5-14 years, are encouraged to get vaccinated against influenza before the epidemic seasons.

PMID:38847280 | DOI:10.1080/21645515.2024.2363076

Categories: Literature Watch

Establishment and development of the Center of Plant Systems Biology and Biotechnology in Plovdiv, Bulgaria

Fri, 2024-06-07 06:00

Open Res Eur. 2024 Jan 29;3:140. doi: 10.12688/openreseurope.16514.2. eCollection 2023.

ABSTRACT

The Bulgarian research landscape, presented mainly by the research institutes that are part of the Bulgarian Academy of Sciences and the Agricultural Academy, needs diversification to match the research and innovation potential of the other European Union (EU) countries. This article describes the establishment of the Center of Plant Systems Biology and Biotechnology (CPSBB), a new innovative type of independent research organization that is changing the research landscape in Bulgaria. Supported by the EU Commission, Bulgarian Government, and Plovdiv Municipality, CPSBB has quickly become the leading plant science institute in Bulgaria, creating knowledge in diverse fields such as bioinformatics, biotechnology, genetics and genomics, metabolomics, and systems biology. We outline the organizational structure of CPSBB, the development of its infrastructure, and its scientific productivity. Finally, we compare CPSBB with other similar research establishments in Europe and we conclude that such new types of institutes have a bright future in Bulgaria due to their operational flexibility, productivity, and connections with academia and industry.

PMID:38846177 | PMC:PMC11153986 | DOI:10.12688/openreseurope.16514.2

Categories: Literature Watch

TMErisk score: A tumor microenvironment-based model for predicting prognosis and immunotherapy in patients with head and neck squamous cell carcinoma

Fri, 2024-06-07 06:00

Heliyon. 2024 May 23;10(11):e31877. doi: 10.1016/j.heliyon.2024.e31877. eCollection 2024 Jun 15.

ABSTRACT

Tumor microenvironment (TME) is closely associated with the progression and prognosis of head and neck squamous cell carcinoma (HNSCC). To investigate potential biomarkers for predicting therapeutic outcomes in HNSCC, we analyzed the immune and stromal status of HNSCC based on the genes associated with TME using the ESTIMATE algorithm. Immune and stromal genes were identified with differential gene expression and weighted gene co-expression network analysis (WGCNA). From these genes, 118 were initially selected through Cox univariate regression and then further input into least absolute shrinkage and selection operator (LASSO) regression analysis. As a result, 11 genes were screened out for the TME-related risk (TMErisk) score model which presented promising overall survival predictive potential. The TMErisk score was negatively associated with immune and stromal scores but positively associated with tumor purity. Individuals with high TMErisk scores exhibited decreased expression of most immune checkpoints and all human leukocyte antigen family genes, and reduced abundance of infiltrating immune cells. Divergent genes were mutated in HNSCC. In both high and low TMErisk score groups, the tumor protein P53 exhibited the highest mutation frequency. A higher TMErisk score was found to be associated with reduced overall survival probability and worse outcomes of immunotherapy. Therefore, the TMErisk score could serve as a valuable model for the outcome prediction of HNSCC in clinic.

PMID:38845978 | PMC:PMC11152963 | DOI:10.1016/j.heliyon.2024.e31877

Categories: Literature Watch

Gut microbiota depletion delays somatic peripheral nerve development and impairs neuromuscular junction maturation

Fri, 2024-06-07 06:00

Gut Microbes. 2024 Jan-Dec;16(1):2363015. doi: 10.1080/19490976.2024.2363015. Epub 2024 Jun 7.

ABSTRACT

Gut microbiota is responsible for essential functions in human health. Several communication axes between gut microbiota and other organs via neural, endocrine, and immune pathways have been described, and perturbation of gut microbiota composition has been implicated in the onset and progression of an emerging number of diseases. Here, we analyzed peripheral nerves, dorsal root ganglia (DRG), and skeletal muscles of neonatal and young adult mice with the following gut microbiota status: a) germ-free (GF), b) gnotobiotic, selectively colonized with 12 specific gut bacterial strains (Oligo-Mouse-Microbiota, OMM12), or c) natural complex gut microbiota (CGM). Stereological and morphometric analyses revealed that the absence of gut microbiota impairs the development of somatic median nerves, resulting in smaller diameter and hypermyelinated axons, as well as in smaller unmyelinated fibers. Accordingly, DRG and sciatic nerve transcriptomic analyses highlighted a panel of differentially expressed developmental and myelination genes. Interestingly, the type III isoform of Neuregulin1 (NRG1), known to be a neuronal signal essential for Schwann cell myelination, was overexpressed in young adult GF mice, with consequent overexpression of the transcription factor Early Growth Response 2 (Egr2), a fundamental gene expressed by Schwann cells at the onset of myelination. Finally, GF status resulted in histologically atrophic skeletal muscles, impaired formation of neuromuscular junctions, and deregulated expression of related genes. In conclusion, we demonstrate for the first time a gut microbiota regulatory impact on proper development of the somatic peripheral nervous system and its functional connection to skeletal muscles, thus suggesting the existence of a novel 'Gut Microbiota-Peripheral Nervous System-axis.'

PMID:38845453 | DOI:10.1080/19490976.2024.2363015

Categories: Literature Watch

Robust prediction of relative binding energies for protein-protein complex mutations using free energy perturbation calculations

Thu, 2024-06-06 06:00

J Mol Biol. 2024 Jun 4:168640. doi: 10.1016/j.jmb.2024.168640. Online ahead of print.

ABSTRACT

Computational free energy-based methods have the potential to significantly improve throughput and decrease costs of protein design efforts. Such methods must reach a high level of reliability, accuracy, and automation to be effectively deployed in practical industrial settings in a way that impacts protein design projects. Here, we present a benchmark study for the calculation of relative changes in protein-protein binding affinity for single point mutations across a variety of systems from the literature, using free energy perturbation (FEP+) calculations. We describe a method for robust treatment of alternate protonation states for titratable amino acids, which yields improved correlation with and reduced error compared to experimental binding free energies. Following careful analysis of the largest outlier cases in our dataset, we assess limitations of the default FEP+ protocols and introduce an automated script which identifies probable outlier cases that may require additional scrutiny and calculates an empirical correction for a subset of charge-related outliers. Through a series of three additional case study systems, we discuss how protein FEP+ can be applied to real-world protein design projects, and suggest areas of further study.

PMID:38844044 | DOI:10.1016/j.jmb.2024.168640

Categories: Literature Watch

DNA methylation patterns of transcription factor binding regions characterize their functional and evolutionary contexts

Thu, 2024-06-06 06:00

Genome Biol. 2024 Jun 6;25(1):146. doi: 10.1186/s13059-024-03218-6.

ABSTRACT

BACKGROUND: DNA methylation is an important epigenetic modification which has numerous roles in modulating genome function. Its levels are spatially correlated across the genome, typically high in repressed regions but low in transcription factor (TF) binding sites and active regulatory regions. However, the mechanisms establishing genome-wide and TF binding site methylation patterns are still unclear.

RESULTS: Here we use a comparative approach to investigate the association of DNA methylation to TF binding evolution in mammals. Specifically, we experimentally profile DNA methylation and combine this with published occupancy profiles of five distinct TFs (CTCF, CEBPA, HNF4A, ONECUT1, FOXA1) in the liver of five mammalian species (human, macaque, mouse, rat, dog). TF binding sites are lowly methylated, but they often also have intermediate methylation levels. Furthermore, biding sites are influenced by the methylation status of CpGs in their wider binding regions even when CpGs are absent from the core binding motif. Employing a classification and clustering approach, we extract distinct and species-conserved patterns of DNA methylation levels at TF binding regions. CEBPA, HNF4A, ONECUT1, and FOXA1 share the same methylation patterns, while CTCF's differ. These patterns characterize alternative functions and chromatin landscapes of TF-bound regions. Leveraging our phylogenetic framework, we find DNA methylation gain upon evolutionary loss of TF occupancy, indicating coordinated evolution. Furthermore, each methylation pattern has its own evolutionary trajectory reflecting its genomic contexts.

CONCLUSIONS: Our epigenomic analyses indicate a role for DNA methylation in TF binding changes across species including that specific DNA methylation profiles characterize TF binding and are associated with their regulatory activity, chromatin contexts, and evolutionary trajectories.

PMID:38844976 | DOI:10.1186/s13059-024-03218-6

Categories: Literature Watch

Using expression data to fine map QTL associated with fertility in dairy cattle

Thu, 2024-06-06 06:00

Genet Sel Evol. 2024 Jun 6;56(1):42. doi: 10.1186/s12711-024-00912-8.

ABSTRACT

BACKGROUND: Female fertility is an important trait in dairy cattle. Identifying putative causal variants associated with fertility may help to improve the accuracy of genomic prediction of fertility. Combining expression data (eQTL) of genes, exons, gene splicing and allele specific expression is a promising approach to fine map QTL to get closer to the causal mutations. Another approach is to identify genomic differences between cows selected for high and low fertility and a selection experiment in New Zealand has created exactly this resource. Our objective was to combine multiple types of expression data, fertility traits and allele frequency in high- (POS) and low-fertility (NEG) cows with a genome-wide association study (GWAS) on calving interval in Australian cows to fine-map QTL associated with fertility in both Australia and New Zealand dairy cattle populations.

RESULTS: Variants that were significantly associated with calving interval (CI) were strongly enriched for variants associated with gene, exon, gene splicing and allele-specific expression, indicating that there is substantial overlap between QTL associated with CI and eQTL. We identified 671 genes with significant differential expression between POS and NEG cows, with the largest fold change detected for the CCDC196 gene on chromosome 10. Our results provide numerous candidate genes associated with female fertility in dairy cattle, including GYS2 and TIGAR on chromosome 5 and SYT3 and HSD17B14 on chromosome 18. Multiple QTL regions were located in regions with large numbers of copy number variants (CNV). To identify the causal mutations for these variants, long read sequencing may be useful.

CONCLUSIONS: Variants that were significantly associated with CI were highly enriched for eQTL. We detected 671 genes that were differentially expressed between POS and NEG cows. Several QTL detected for CI overlapped with eQTL, providing candidate genes for fertility in dairy cattle.

PMID:38844868 | DOI:10.1186/s12711-024-00912-8

Categories: Literature Watch

Central transcriptional regulator controls photosynthetic growth and carbon storage in response to high light

Thu, 2024-06-06 06:00

Nat Commun. 2024 Jun 6;15(1):4842. doi: 10.1038/s41467-024-49090-7.

ABSTRACT

Carbon capture and biochemical storage are some of the primary drivers of photosynthetic yield and productivity. To elucidate the mechanisms governing carbon allocation, we designed a photosynthetic light response test system for genetic and metabolic carbon assimilation tracking, using microalgae as simplified plant models. The systems biology mapping of high light-responsive photophysiology and carbon utilization dynamics between two variants of the same Picochlorum celeri species, TG1 and TG2 elucidated metabolic bottlenecks and transport rates of intermediates using instationary 13C-fluxomics. Simultaneous global gene expression dynamics showed 73% of the annotated genes responding within one hour, elucidating a singular, diel-responsive transcription factor, closely related to the CCA1/LHY clock genes in plants, with significantly altered expression in TG2. Transgenic P. celeri TG1 cells expressing the TG2 CCA1/LHY gene, showed 15% increase in growth rates and 25% increase in storage carbohydrate content, supporting a coordinating regulatory function for a single transcription factor.

PMID:38844786 | DOI:10.1038/s41467-024-49090-7

Categories: Literature Watch

Large-scale foundation model on single-cell transcriptomics

Thu, 2024-06-06 06:00

Nat Methods. 2024 Jun 6. doi: 10.1038/s41592-024-02305-7. Online ahead of print.

ABSTRACT

Large pretrained models have become foundation models leading to breakthroughs in natural language processing and related fields. Developing foundation models for deciphering the 'languages' of cells and facilitating biomedical research is promising yet challenging. Here we developed a large pretrained model scFoundation, also named 'xTrimoscFoundationα', with 100 million parameters covering about 20,000 genes, pretrained on over 50 million human single-cell transcriptomic profiles. scFoundation is a large-scale model in terms of the size of trainable parameters, dimensionality of genes and volume of training data. Its asymmetric transformer-like architecture and pretraining task design empower effectively capturing complex context relations among genes in a variety of cell types and states. Experiments showed its merit as a foundation model that achieved state-of-the-art performances in a diverse array of single-cell analysis tasks such as gene expression enhancement, tissue drug response prediction, single-cell drug response classification, single-cell perturbation prediction, cell type annotation and gene module inference.

PMID:38844628 | DOI:10.1038/s41592-024-02305-7

Categories: Literature Watch

Pre-hypertrophic chondrogenic enhancer landscape of limb and axial skeleton development

Thu, 2024-06-06 06:00

Nat Commun. 2024 Jun 6;15(1):4820. doi: 10.1038/s41467-024-49203-2.

ABSTRACT

Chondrocyte differentiation controls skeleton development and stature. Here we provide a comprehensive map of chondrocyte-specific enhancers and show that they provide a mechanistic framework through which non-coding genetic variants can influence skeletal development and human stature. Working with fetal chondrocytes isolated from mice bearing a Col2a1 fluorescent regulatory sensor, we identify 780 genes and 2'704 putative enhancers specifically active in chondrocytes using a combination of RNA-seq, ATAC-seq and H3K27ac ChIP-seq. Most of these enhancers (74%) show pan-chondrogenic activity, with smaller populations being restricted to limb (18%) or trunk (8%) chondrocytes only. Notably, genetic variations overlapping these enhancers better explain height differences than those overlapping non-chondrogenic enhancers. Finally, targeted deletions of identified enhancers at the Fgfr3, Col2a1, Hhip and, Nkx3-2 loci confirm their role in regulating cognate genes. This enhancer map provides a framework for understanding how genes and non-coding variations influence bone development and diseases.

PMID:38844479 | DOI:10.1038/s41467-024-49203-2

Categories: Literature Watch

Cis-regulatory evolution of the recently expanded Ly49 gene family

Thu, 2024-06-06 06:00

Nat Commun. 2024 Jun 6;15(1):4839. doi: 10.1038/s41467-024-48990-y.

ABSTRACT

Comparative genomics has revealed the rapid expansion of multiple gene families involved in immunity. Members within each gene family often evolved distinct roles in immunity. However, less is known about the evolution of their epigenome and cis-regulation. Here we systematically profile the epigenome of the recently expanded murine Ly49 gene family that mainly encode either inhibitory or activating surface receptors on natural killer cells. We identify a set of cis-regulatory elements (CREs) for activating Ly49 genes. In addition, we show that in mice, inhibitory and activating Ly49 genes are regulated by two separate sets of proximal CREs, likely resulting from lineage-specific losses of CRE activity. Furthermore, we find that some Ly49 genes are cross-regulated by the CREs of other Ly49 genes, suggesting that the Ly49 family has begun to evolve a concerted cis-regulatory mechanism. Collectively, we demonstrate the different modes of cis-regulatory evolution for a rapidly expanding gene family.

PMID:38844462 | DOI:10.1038/s41467-024-48990-y

Categories: Literature Watch

Tau propagation in the brain olfactory circuits is associated with smell perception changes in aging

Thu, 2024-06-06 06:00

Nat Commun. 2024 Jun 6;15(1):4809. doi: 10.1038/s41467-024-48462-3.

ABSTRACT

The direct access of olfactory afferents to memory-related cortical systems has inspired theories about the role of the olfactory pathways in the development of cortical neurodegeneration in Alzheimer's disease (AD). In this study, we used baseline olfactory identification measures with longitudinal flortaucipir and PiB PET, diffusion MRI of 89 cognitively normal older adults (73.82 ± 8.44 years; 56% females), and a transcriptomic data atlas to investigate the spatiotemporal spreading and genetic vulnerabilities of AD-related pathology aggregates in the olfactory system. We find that odor identification deficits are predominantly associated with tau accumulation in key areas of the olfactory pathway, with a particularly strong predictive power for longitudinal tau progression. We observe that tau spreads from the medial temporal lobe structures toward the olfactory system, not the reverse. Moreover, we observed a genetic background of odor perception-related genes that might confer vulnerability to tau accumulation along the olfactory system.

PMID:38844444 | DOI:10.1038/s41467-024-48462-3

Categories: Literature Watch

Axis formation in annual killifish: Nodal and β-catenin regulate morphogenesis without Huluwa prepatterning

Thu, 2024-06-06 06:00

Science. 2024 Jun 7;384(6700):1105-1110. doi: 10.1126/science.ado7604. Epub 2024 Jun 6.

ABSTRACT

Axis formation in fish and amphibians typically begins with a prepattern of maternal gene products. Annual killifish embryogenesis, however, challenges prepatterning models as blastomeres disperse and then aggregate to form the germ layers and body axes. We show that huluwa, a prepatterning factor thought to break symmetry by stabilizing β-catenin, is truncated and inactive in Nothobranchius furzeri. Nuclear β-catenin is not selectively stabilized on one side of the blastula but accumulates in cells forming the aggregate. Blocking β-catenin activity or Nodal signaling disrupts aggregate formation and germ layer specification. Nodal signaling coordinates cell migration, establishing an early role for this signaling pathway. These results reveal a surprising departure from established mechanisms of axis formation: Huluwa-mediated prepatterning is dispensable, and β-catenin and Nodal regulate morphogenesis.

PMID:38843334 | DOI:10.1126/science.ado7604

Categories: Literature Watch

Determining the ERK-regulated phosphoproteome driving KRAS-mutant cancer

Thu, 2024-06-06 06:00

Science. 2024 Jun 7;384(6700):eadk0850. doi: 10.1126/science.adk0850. Epub 2024 Jun 7.

ABSTRACT

To delineate the mechanisms by which the ERK1 and ERK2 mitogen-activated protein kinases support mutant KRAS-driven cancer growth, we determined the ERK-dependent phosphoproteome in KRAS-mutant pancreatic cancer. We determined that ERK1 and ERK2 share near-identical signaling and transforming outputs and that the KRAS-regulated phosphoproteome is driven nearly completely by ERK. We identified 4666 ERK-dependent phosphosites on 2123 proteins, of which 79 and 66%, respectively, were not previously associated with ERK, substantially expanding the depth and breadth of ERK-dependent phosphorylation events and revealing a considerably more complex function for ERK in cancer. We established that ERK controls a highly dynamic and complex phosphoproteome that converges on cyclin-dependent kinase regulation and RAS homolog guanosine triphosphatase function (RHO GTPase). Our findings establish the most comprehensive molecular portrait and mechanisms by which ERK drives KRAS-dependent pancreatic cancer growth.

PMID:38843329 | DOI:10.1126/science.adk0850

Categories: Literature Watch

Cellular architecture shapes the naïve T cell response

Thu, 2024-06-06 06:00

Science. 2024 Jun 7;384(6700):eadh8697. doi: 10.1126/science.adh8967. Epub 2024 Jun 7.

ABSTRACT

After antigen stimulation, naïve T cells display reproducible population-level responses, which arise from individual T cells pursuing specific differentiation trajectories. However, cell-intrinsic predeterminants controlling these single-cell decisions remain enigmatic. We found that the subcellular architectures of naïve CD8 T cells, defined by the presence (TØ) or absence (TO) of nuclear envelope invaginations, changed with maturation, activation, and differentiation. Upon T cell receptor (TCR) stimulation, naïve TØ cells displayed increased expression of the early-response gene Nr4a1, dependent upon heightened calcium entry. Subsequently, in vitro differentiation revealed that TØ cells generated effector-like cells more so compared with TO cells, which proliferated less and preferentially adopted a memory-precursor phenotype. These data suggest that cellular architecture may be a predeterminant of naïve CD8 T cell fate.

PMID:38843327 | DOI:10.1126/science.adh8967

Categories: Literature Watch

Genome-wide identification and characterization of DTX family genes highlighting their locations, functions, and regulatory factors in banana (Musa acuminata)

Thu, 2024-06-06 06:00

PLoS One. 2024 Jun 6;19(6):e0303065. doi: 10.1371/journal.pone.0303065. eCollection 2024.

ABSTRACT

The detoxification efflux carriers (DTX) are a significant group of multidrug efflux transporter family members that play diverse functions in all kingdoms of living organisms. However, genome-wide identification and characterization of DTX family transporters have not yet been performed in banana, despite its importance as an economic fruit plant. Therefore, a detailed genome-wide analysis of DTX family transporters in banana (Musa acuminata) was conducted using integrated bioinformatics and systems biology approaches. In this study, a total of 37 DTX transporters were identified in the banana genome and divided into four groups (I, II, III, and IV) based on phylogenetic analysis. The gene structures, as well as their proteins' domains and motifs, were found to be significantly conserved. Gene ontology (GO) annotation revealed that the predicted DTX genes might play a vital role in protecting cells and membrane-bound organelles through detoxification mechanisms and the removal of drug molecules from banana cells. Gene regulatory analyses identified key transcription factors (TFs), cis-acting elements, and post-transcriptional regulators (miRNAs) of DTX genes, suggesting their potential roles in banana. Furthermore, the changes in gene expression levels due to pathogenic infections and non-living factor indicate that banana DTX genes play a role in responses to both biotic and abiotic stresses. The results of this study could serve as valuable tools to improve banana quality by protecting them from a range of environmental stresses.

PMID:38843276 | DOI:10.1371/journal.pone.0303065

Categories: Literature Watch

YjgA plays dual roles in enhancing PTC maturation

Thu, 2024-06-06 06:00

Nucleic Acids Res. 2024 Jun 6:gkae469. doi: 10.1093/nar/gkae469. Online ahead of print.

ABSTRACT

Ribosome biogenesis is a highly regulated cellular process that involves the control of numerous assembly factors. The small protein YjgA has been reported to play a role in the late stages of 50S assembly. However, the precise molecular mechanism underlying its function remains unclear. In this study, cryo-electron microscopy (cryo-EM) structures revealed that depletion of YjgA or its N-terminal loop in Escherichia coli both lead to the accumulation of immature 50S particles with structural abnormalities mainly in peptidyl transferase center (PTC) and H68/69 region. CryoDRGN analysis uncovered 8 and 6 distinct conformations of pre50S for ΔyjgA and YjgA-ΔNloop, respectively. These conformations highlighted the role of the N-terminal loop of YjgA in integrating uL16 and stabilizing H89 in PTC, which was further verified by the pull-down assays of YjgA and its mutants with uL16. Together with the function of undocking H68 through the binding of its C-terminal CTLH-like domain to the base of the L1 stalk, YjgA facilitates the maturation of PTC. This study identified critical domains of YjgA contributing to 50S assembly efficiency, providing a comprehensive understanding of the dual roles of YjgA in accelerating ribosome biogenesis and expanding our knowledge of the intricate processes governing cellular protein synthesis.

PMID:38842932 | DOI:10.1093/nar/gkae469

Categories: Literature Watch

Liam tackles complex multimodal single-cell data integration challenges

Thu, 2024-06-06 06:00

Nucleic Acids Res. 2024 Jun 6:gkae409. doi: 10.1093/nar/gkae409. Online ahead of print.

ABSTRACT

Multi-omics characterization of single cells holds outstanding potential for profiling the dynamics and relations of gene regulatory states of thousands of cells. How to integrate multimodal data is an open problem, especially when aiming to combine data from multiple sources or conditions containing both biological and technical variation. We introduce liam, a flexible model for the simultaneous horizontal and vertical integration of paired single-cell multimodal data and mosaic integration of paired with unimodal data. Liam learns a joint low-dimensional representation of the measured modalities, which proves beneficial when the information content or quality of the modalities differ. Its integration accounts for complex batch effects using a tunable combination of conditional and adversarial training, which can be optimized using replicate information while retaining selected biological variation. We demonstrate liam's superior performance on multiple paired multimodal data types, including Multiome and CITE-seq data, and in mosaic integration scenarios. Our detailed benchmarking experiments illustrate the complexities and challenges remaining for integration and the meaningful assessment of its success.

PMID:38842910 | DOI:10.1093/nar/gkae409

Categories: Literature Watch

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