Systems Biology
A new piece of the microbiota pie: Mining 'omics for DNA inversion states
Cell Host Microbe. 2024 Mar 13;32(3):293-295. doi: 10.1016/j.chom.2024.02.009.
ABSTRACT
In this issue of Cell Host & Microbe, Carasso et al. survey invertible DNA sites in Bacteroidales from patients with inflammatory bowel disease (IBD) and healthy control individuals. They identify complex functional interactions between Bacteroides fragilis, an invertible promoter, a capsular polysaccharide, a bacteriophage, and the human host. The establishment of 'omics approaches to characterizing genomic targets and functional roles is still required.
PMID:38484706 | DOI:10.1016/j.chom.2024.02.009
Deciphering Breast Cancer Metastasis Cascade: A Systems Biology Approach Integrating Transcriptome and Interactome Insights for Target Discovery
OMICS. 2024 Mar 14. doi: 10.1089/omi.2023.0285. Online ahead of print.
ABSTRACT
Breast cancer is the lead cause of cancer-related deaths among women globally. Breast cancer metastasis is a complex and still inadequately understood process and a key dimension of mortality attendant to breast cancer. This study reports dysregulated genes across metastatic stages and tissues, shedding light on their molecular interplay in disease pathogenesis and new possibilities for drug discovery. Comprehensive analyses of gene expression data from primary breast tumor, circulating tumor cells, and distant metastatic sites in the brain, lung, liver, and bone were conducted. Genes dysregulated across multiple stages and tissues were identified as metastatic cascade genes, and are further classified based on functional associations with metastasis-related mechanisms. Their interactions with HUB genes in interactome networks were scrutinized, followed by pathway enrichment analysis. Validation for their potential as targets included assessments for survival, druggability, prognostic marker status, secretome annotation, protein expression, and cell type marker association. Results displayed critical genes in the metastatic cascade and those specific to metastatic sites, revealing the involvement of the collagen degradation and assembly of collagen fibrils and other multimeric structure pathways in driving metastasis. Notably, pivotal cascade genes FABP4, CXCL12, APOD, and IGF1 emerged with high metastatic potential, linked to significant druggability and survival scores, establishing them as potential molecular targets. The significance of this research lies in its potential to uncover novel biomarkers for early detection, therapeutic targets, and a deeper understanding of the molecular mechanisms underpinning the metastatic cascade in breast cancer, and with an eye to precision/personalized medicine.
PMID:38484298 | DOI:10.1089/omi.2023.0285
Antibacterial activity of nonantibiotics is orthogonal to standard antibiotics
Science. 2024 Mar 14:eadk7368. doi: 10.1126/science.adk7368. Online ahead of print.
ABSTRACT
Numerous nonantibiotic drugs have potent antibacterial activity and can adversely impact the human microbiome. The mechanistic underpinning of this toxicity remains largely unknown. We investigated the antibacterial activity of 200 drugs using genetic screens with thousands of barcoded Escherichia coli knockouts. We analyzed 2 million gene-drug interactions underlying drug-specific toxicity. Network-based analysis of drug-drug similarities revealed that antibiotics clustered into modules consistent with the mode of action of their established classes, while nonantibiotics remained unconnected. Half of the nonantibiotics clustered into separate modules, potentially revealing shared and unexploited targets for novel antimicrobials. Analysis of efflux systems revealed they widely impact antibiotics and nonantibiotics alike, suggesting that the impact of nonantibiotics on antibiotic cross-resistance should be investigated closely in vivo.
PMID:38484036 | DOI:10.1126/science.adk7368
An analytically tractable, age-structured model of the impact of vector control on mosquito-transmitted infections
PLoS Comput Biol. 2024 Mar 14;20(3):e1011440. doi: 10.1371/journal.pcbi.1011440. Online ahead of print.
ABSTRACT
Vector control is a vital tool utilised by malaria control and elimination programmes worldwide, and as such it is important that we can accurately quantify the expected public health impact of these methods. There are very few previous models that consider vector-control-induced changes in the age-structure of the vector population and the resulting impact on transmission. We analytically derive the steady-state solution of a novel age-structured deterministic compartmental model describing the mosquito feeding cycle, with mosquito age represented discretely by parity-the number of cycles (or successful bloodmeals) completed. Our key model output comprises an explicit, analytically tractable solution that can be used to directly quantify key transmission statistics, such as the effective reproductive ratio under control, Rc, and investigate the age-structured impact of vector control. Application of this model reinforces current knowledge that adult-acting interventions, such as indoor residual spraying of insecticides (IRS) or long-lasting insecticidal nets (LLINs), can be highly effective at reducing transmission, due to the dual effects of repelling and killing mosquitoes. We also demonstrate how larval measures can be implemented in addition to adult-acting measures to reduce Rc and mitigate the impact of waning insecticidal efficacy, as well as how mid-ranges of LLIN coverage are likely to experience the largest effect of reduced net integrity on transmission. We conclude that whilst well-maintained adult-acting vector control measures are substantially more effective than larval-based interventions, incorporating larval control in existing LLIN or IRS programmes could substantially reduce transmission and help mitigate any waning effects of adult-acting measures.
PMID:38484022 | DOI:10.1371/journal.pcbi.1011440
Endogenous retrovirus HERVH-derived lncRNA <em>UCA1</em> controls human trophoblast development
Proc Natl Acad Sci U S A. 2024 Mar 19;121(12):e2318176121. doi: 10.1073/pnas.2318176121. Epub 2024 Mar 14.
ABSTRACT
Endogenous retroviruses (ERVs) are frequently reactivated in mammalian placenta. It has been proposed that ERVs contribute to shaping the gene regulatory network of mammalian trophoblasts, dominantly acting as species- and placental-specific enhancers. However, whether and how ERVs control human trophoblast development through alternative pathways remains poorly understood. Besides the well-recognized function of human endogenous retrovirus-H (HERVH) in maintaining pluripotency of early human epiblast, here we present a unique role of HERVH on trophoblast lineage development. We found that the LTR7C/HERVH subfamily exhibits an accessible chromatin state in the human trophoblast lineage. Particularly, the LTR7C/HERVH-derived Urothelial Cancer Associated 1 (UCA1), a primate-specific long non-coding RNA (lncRNA), is transcribed in human trophoblasts and promotes the proliferation of human trophoblast stem cells (hTSCs), whereas its ectopic expression compromises human trophoblast syncytialization coinciding with increased interferon signaling pathway. Importantly, UCA1 upregulation is detectable in placental samples from early-onset preeclampsia (EO-PE) patients and the transcriptome of EO-PE placenta exhibits considerable similarities to that of the syncytiotrophoblasts differentiated from UCA1-overexpressing hTSCs, supporting up-regulated UCA1 as a potential biomarker of this disease. Altogether, our data shed light on the versatile regulatory role of HERVH in early human development and provide a unique mechanism whereby ERVs exert a function in human placentation and placental syndromes.
PMID:38483994 | DOI:10.1073/pnas.2318176121
A common <em>cis-</em>regulatory variant impacts normal-range and disease-associated human facial shape through regulation of <em>PKDCC</em> during chondrogenesis
Elife. 2024 Mar 14;13:e82564. doi: 10.7554/eLife.82564.
ABSTRACT
Genome-wide association studies (GWAS) identified thousands of genetic variants linked to phenotypic traits and disease risk. However, mechanistic understanding of how GWAS variants influence complex morphological traits and can, in certain cases, simultaneously confer normal-range phenotypic variation and disease predisposition, is still largely lacking. Here, we focus on rs6740960, a single nucleotide polymorphism (SNP) at the 2p21 locus, which in GWAS studies has been associated both with normal-range variation in jaw shape and with an increased risk of non-syndromic orofacial clefting. Using in vitro derived embryonic cell types relevant for human facial morphogenesis, we show that this SNP resides in an enhancer that regulates chondrocytic expression of PKDCC - a gene encoding a tyrosine kinase involved in chondrogenesis and skeletal development. In agreement, we demonstrate that the rs6740960 SNP is sufficient to confer chondrocyte-specific differences in PKDCC expression. By deploying dense landmark morphometric analysis of skull elements in mice, we show that changes in Pkdcc dosage are associated with quantitative changes in the maxilla, mandible, and palatine bone shape that are concordant with the facial phenotypes and disease predisposition seen in humans. We further demonstrate that the frequency of the rs6740960 variant strongly deviated among different human populations, and that the activity of its cognate enhancer diverged in hominids. Our study provides a mechanistic explanation of how a common SNP can mediate normal-range and disease-associated morphological variation, with implications for the evolution of human facial features.
PMID:38483448 | DOI:10.7554/eLife.82564
Computational and Systems Biology Advances to Enable Bioagent Agnostic Signatures
Health Secur. 2024 Mar 13. doi: 10.1089/hs.2023.0076. Online ahead of print.
NO ABSTRACT
PMID:38483337 | DOI:10.1089/hs.2023.0076
Neurobiology and systems biology of stress resilience
Physiol Rev. 2024 Mar 14. doi: 10.1152/physrev.00042.2023. Online ahead of print.
ABSTRACT
Stress resilience is the phenomenon that some people maintain their mental health despite exposure to adversity or show only temporary impairments followed by quick recovery. Resilience research attempts to unravel the factors and mechanisms that make resilience possible and to harness its insights for the development of preventative interventions in individuals at risk for acquiring stress-related dysfunctions. Biological resilience research has been lagging behind the psychological and social sciences, but has seen a massive surge in recent years. At the same time, progress in this field has been hampered by methodological challenges related to finding suitable operationalizations and study designs, replicating findings, and modeling resilience in animals. We embed a review of behavioral, neuroimaging, neurobiological, and systems-biological findings in adults in a critical methods discussion. We find preliminary evidence that hippocampal-based pattern separation and prefrontal-based cognitive control functions protect against the development of pathological fears in the aftermath of singular, event-type stressors (as found in fear-related disorders, including simpler forms of post-traumatic stress disorder, PTSD), by facilitating the perception of safety. Reward system-based pursuit and savoring of positive reinforcers appear to protect against the development of more generalized dysfunctions of the anxious-depressive spectrum resulting from more severe or longer-lasting stressors (as in depression, generalized or comorbid anxiety, or severe PTSD). Links between preserved functioning of these neural systems under stress and neuroplasticity, immunoregulation, gut microbiome composition, and integrity of the gut barrier and the blood-brain barrier are beginning to emerge. On this basis, avenues for biological interventions are pointed out.
PMID:38483288 | DOI:10.1152/physrev.00042.2023
SuperCUT, an unsupervised multimodal image registration with deep learning for biomedical microscopy
Brief Bioinform. 2024 Jan 22;25(2):bbae029. doi: 10.1093/bib/bbae029.
ABSTRACT
Numerous imaging techniques are available for observing and interrogating biological samples, and several of them can be used consecutively to enable correlative analysis of different image modalities with varying resolutions and the inclusion of structural or molecular information. Achieving accurate registration of multimodal images is essential for the correlative analysis process, but it remains a challenging computer vision task with no widely accepted solution. Moreover, supervised registration methods require annotated data produced by experts, which is limited. To address this challenge, we propose a general unsupervised pipeline for multimodal image registration using deep learning. We provide a comprehensive evaluation of the proposed pipeline versus the current state-of-the-art image registration and style transfer methods on four types of biological problems utilizing different microscopy modalities. We found that style transfer of modality domains paired with fully unsupervised training leads to comparable image registration accuracy to supervised methods and, most importantly, does not require human intervention.
PMID:38483256 | DOI:10.1093/bib/bbae029
You don't win friends with bad salad! A gene editing approach to enhance the powdery mildew resistance in cucumber
Plant Physiol. 2024 Mar 14:kiae160. doi: 10.1093/plphys/kiae160. Online ahead of print.
NO ABSTRACT
PMID:38482927 | DOI:10.1093/plphys/kiae160
Press for MIA production! The role of the Rho of plant GTPases in plant-specialized metabolism
Plant Physiol. 2024 Mar 14:kiae163. doi: 10.1093/plphys/kiae163. Online ahead of print.
NO ABSTRACT
PMID:38482923 | DOI:10.1093/plphys/kiae163
Comprehending phenotypic plasticity in cancer and evolution
iScience. 2024 Mar 5;27(3):109308. doi: 10.1016/j.isci.2024.109308. eCollection 2024 Mar 15.
ABSTRACT
Organisms as well as cancer cells are adept at adapting to changes in the environment in which they find themselves, by actively adjusting their phenotype. Phenotypic plasticity is a quantitative trait that confers a fitness advantage to the organism by tailoring its phenotype to environmental circumstances. While it is generally held that new traits arise solely from genetic factors, emerging evidence indicates that phenotypic plasticity also plays a critical role both in cancer and evolution. Thus, understanding the mechanisms that underlie phenotypic plasticity can not only provide new insights into organismal evolution and the origin of novelty but can also result in novel strategies and therapeutics to treat cancer.
PMID:38482503 | PMC:PMC10933540 | DOI:10.1016/j.isci.2024.109308
Chinmedomics: a potent tool for the evaluation of traditional Chinese medicine efficacy and identification of its active components
Chin Med. 2024 Mar 13;19(1):47. doi: 10.1186/s13020-024-00917-x.
ABSTRACT
As an important part of medical science, Traditional Chinese Medicine (TCM) attracts much public attention due to its multi-target and multi-pathway characteristics in treating diseases. However, the limitations of traditional research methods pose a dilemma for the evaluation of clinical efficacy, the discovery of active ingredients and the elucidation of the mechanism of action. Therefore, innovative approaches that are in line with the characteristics of TCM theory and clinical practice are urgently needed. Chinmendomics, a newly emerging strategy for evaluating the efficacy of TCM, is proposed. This strategy combines systems biology, serum pharmacochemistry of TCM and bioinformatics to evaluate the efficacy of TCM with a holistic view by accurately identifying syndrome biomarkers and monitoring their complex metabolic processes intervened by TCM, and finding the agents associated with the metabolic course of pharmacodynamic biomarkers by constructing a bioinformatics-based correlation network model to further reveal the interaction between agents and pharmacodynamic targets. In this article, we review the recent progress of Chinmedomics to promote its application in the modernisation and internationalisation of TCM.
PMID:38481256 | DOI:10.1186/s13020-024-00917-x
Functional genomic screens with death rate analyses reveal mechanisms of drug action
Nat Chem Biol. 2024 Mar 13. doi: 10.1038/s41589-024-01584-7. Online ahead of print.
ABSTRACT
A common approach for understanding how drugs induce their therapeutic effects is to identify the genetic determinants of drug sensitivity. Because 'chemo-genetic profiles' are performed in a pooled format, inference of gene function is subject to several confounding influences related to variation in growth rates between clones. In this study, we developed Method for Evaluating Death Using a Simulation-assisted Approach (MEDUSA), which uses time-resolved measurements, along with model-driven constraints, to reveal the combination of growth and death rates that generated the observed drug response. MEDUSA is uniquely effective at identifying death regulatory genes. We apply MEDUSA to characterize DNA damage-induced lethality in the presence and absence of p53. Loss of p53 switches the mechanism of DNA damage-induced death from apoptosis to a non-apoptotic death that requires high respiration. These findings demonstrate the utility of MEDUSA both for determining the genetic dependencies of lethality and for revealing opportunities to potentiate chemo-efficacy in a cancer-specific manner.
PMID:38480981 | DOI:10.1038/s41589-024-01584-7
Long-term, non-invasive FTIR detection of low-dose ionizing radiation exposure
Sci Rep. 2024 Mar 13;14(1):6119. doi: 10.1038/s41598-024-56491-7.
ABSTRACT
Non-invasive methods of detecting radiation exposure show promise to improve upon current approaches to biological dosimetry in ease, speed, and accuracy. Here we developed a pipeline that employs Fourier transform infrared (FTIR) spectroscopy in the mid-infrared spectrum to identify a signature of low dose ionizing radiation exposure in mouse ear pinnae over time. Mice exposed to 0.1 to 2 Gy total body irradiation were repeatedly measured by FTIR at the stratum corneum of the ear pinnae. We found significant discriminative power for all doses and time-points out to 90 days after exposure. Classification accuracy was maximized when testing 14 days after exposure (specificity > 0.9 with a sensitivity threshold of 0.9) and dropped by roughly 30% sensitivity at 90 days. Infrared frequencies point towards biological changes in DNA conformation, lipid oxidation and accumulation and shifts in protein secondary structure. Since only hundreds of samples were used to learn the highly discriminative signature, developing human-relevant diagnostic capabilities is likely feasible and this non-invasive procedure points toward rapid, non-invasive, and reagent-free biodosimetry applications at population scales.
PMID:38480827 | DOI:10.1038/s41598-024-56491-7
Structure-based prediction and characterization of photo-crosslinking in native protein-RNA complexes
Nat Commun. 2024 Mar 13;15(1):2279. doi: 10.1038/s41467-024-46429-y.
ABSTRACT
UV-crosslinking of protein and RNA in direct contacts has been widely used to study protein-RNA complexes while our understanding of the photo-crosslinking mechanisms remains poor. This knowledge gap is due to the challenge of precisely mapping the crosslink sites in protein and RNA simultaneously in their native sequence and structural contexts. Here we systematically analyze protein-RNA interactions and photo-crosslinking by bridging crosslinked nucleotides and amino acids mapped using different assays with protein-RNA complex structures. We developed a computational method PxR3D-map which reliably predicts crosslink sites using structural information characterizing protein-RNA interaction interfaces. Analysis of the informative features revealed that photo-crosslinking is facilitated by base stacking with not only aromatic residues, but also dipeptide bonds that involve glycine, and distinct mechanisms are utilized by different RNA-binding domains. Our work suggests protein-RNA photo-crosslinking is highly selective in the cellular environment, which can guide data interpretation and further technology development for UV-crosslinking-based assays.
PMID:38480694 | DOI:10.1038/s41467-024-46429-y
Genetic factors underlying host resistance to Rhipicephalus microplus tick infestation in Braford cattle: a systems biology perspective
Mamm Genome. 2024 Mar 13. doi: 10.1007/s00335-024-10030-x. Online ahead of print.
ABSTRACT
Approximately 80% of the world's cattle are raised in regions with a high risk of tick-borne diseases, resulting in significant economic losses due to parasitism by Rhipicephalus (Boophilus) microplus. However, the lack of a systemic biology approach hampers a comprehensive understanding of tick-host interactions that mediate tick resistance phenotypes. Here, we conducted a genome-wide association study (GWAS) of 2933 Braford cattle and found 340 single-nucleotide polymorphisms (SNPs) associated with tick counts. Gene expression analyses were performed on skin samples obtained from previously tick-exposed heifers with extremely high or low estimated breeding values for R. microplus counts. Evaluations were performed both before and after artificial infestation with ticks. Differentially expressed genes were found within 1-Mb windows centered at significant SNPs from GWAS. A total of 330 genes were related to the breakdown of homeostasis that was induced by larval attachment to bovine skin. Enrichment analysis pointed to a key role of proteolysis and signal transduction via JAK/STAT, NFKB and WNT/beta catenin signaling pathways. Integrative analysis on matrixEQTL revealed two cis-eQTLs and four significant SNPs in the genes peptidyl arginine deiminase type IV (PADI4) and LOC11449251. The integration of genomic data from QTL maps and transcriptome analyses has identified a set of twelve key genes that show significant associations with tick loads. These genes could be key candidates to improve the accuracy of genomic predictions for tick resistance in Braford cattle.
PMID:38480585 | DOI:10.1007/s00335-024-10030-x
Tuning capsid formation dynamics in recombinant adeno-associated virus producing synthetic cell lines to enhance full particle productivity
Biotechnol J. 2024 Mar;19(3):e2400051. doi: 10.1002/biot.202400051.
ABSTRACT
Recombinant adeno-associated virus (rAAV) is widely used as an in vivo delivery vector for gene therapy. It is used in a very large dose, and the large quantities required for broad applications present manufacturing challenges. We have developed a synthetic biology platform of constructing cell lines integrated with essential viral genes which can be induced to produce rAAV without plasmid transfection or virus transduction. Through iterative design-construct-characterization cycles, we have showcased the potential of this synthetic cell production system. Systems characterization of the dynamics of viral transcripts and proteins as well as virus assembly and packaging revealed that the expression level and balance of viral genome and capsid protein are keys to not only the productivity but also the full particle content, an important product quality attribute. Boosting cap gene expression by sequential transfection and integration of multiple copies of the cap gene elevated the rAAV titer to levels on a par with traditional plasmid transfection and virus infection. However, overexpression of the cap gene shifted the balance and kinetics of the genome and capsid. We independently tuned the dynamics of genome amplification and capsid protein synthesis by modulating the induction concentration as well as the time profile, and significantly enhanced full particle content while maintaining a high productivity. This strategy of constructing an inducible stable producer cell line is readily adaptable to rAAV vectors of different serotypes and payloads. It can greatly facilitate scalable production of gene therapy vectors.
PMID:38479988 | DOI:10.1002/biot.202400051
The pseudoentropy of allele frequency trajectories, the persistence of variation, and the effective population size
Biosystems. 2024 Mar 11:105176. doi: 10.1016/j.biosystems.2024.105176. Online ahead of print.
ABSTRACT
To concisely describe how genetic variation, at individual loci or across whole genomes, changes over time, and to follow transitory allelic changes, we introduce a quantity related to entropy, that we term pseudoentropy. This quantity emerges in a diffusion analysis of the mean time a mutation segregates in a population. For a neutral locus with an arbitrary number of alleles, the mean time of segregation is generally proportional to the pseudoentropy of initial allele frequencies. After the initial time point, pseudoentropy generally decreases, but other behaviours are possible, depending on the genetic diversity and selective forces present. For a biallelic locus, pseudoentropy and entropy coincide, but they are distinct quantities with more than two alleles. Thus for populations with multiple biallelic loci, the language of entropy suffices. Then entropy, combined across loci, serves as a concise description of genetic variation. We used individual based simulations to explore how this entropy behaves under different evolutionary scenarios. In agreement with predictions, the entropy associated with unlinked neutral loci decreases over time. However, deviations from free recombination and neutrality have clear and informative effects on the entropy's behaviour over time. Analysis of publicly available data of a natural D. melanogaster population, that had been sampled over seven years, using a sliding-window approach, yielded considerable variation in entropy trajectories of different genomic regions. These mostly follow a pattern that suggests a substantial effective population size and a limited effect of positive selection on genome-wide diversity over short time scales.
PMID:38479654 | DOI:10.1016/j.biosystems.2024.105176
A global phosphosite-correlated network map of Thousand And One Kinase 1 (TAOK1)
Int J Biochem Cell Biol. 2024 Mar 11:106558. doi: 10.1016/j.biocel.2024.106558. Online ahead of print.
ABSTRACT
Thousand and one amino acid kinase 1 (TAOK1) is a sterile 20 family Serine/Threonine kinase linked to microtubule dynamics, checkpoint signaling, DNA damage response, and neurological functions. Molecular-level alterations of TAOK1 have been associated with neurodevelopment disorders and cancers. Despite their known involvement in physiological and pathophysiological processes, and as a core member of the hippo signaling pathway, the phosphoregulatory network of TAOK1 has not been visualized. Aimed to explore this network, we first analyzed the predominantly detected and differentially regulated TAOK1 phosphosites in global phosphoproteome datasets across diverse experimental conditions. Based on 709 qualitative and 210 quantitative differential cellular phosphoproteome datasets that were systematically assembled, we identified that phosphorylation at Ser421, Ser9, Ser965, and Ser445 predominantly represented TAOK1 in almost 75% of these datasets. Surprisingly, the functional role of all these phosphosites in TAOK1 remains unexplored. Hence, we employed a robust strategy to extract the phosphosites in proteins that significantly correlated in expression with predominant TAOK1 phosphosites. This led to the first categorization of the phosphosites including those in the currently known and predicted interactors, kinases, and substrates, that positively/negatively correlated with the expression status of each predominant TAOK1 phosphosites. Subsequently, we also analyzed the phosphosites in core proteins of the hippo signaling pathway. Based on the TAOK1 phosphoregulatory network analysis, we inferred the potential role of the predominant TAOK1 phosphosites. Especially, we propose pSer9 as an autophosphorylation and TAOK1 kinase activity-associated phosphosite and pS421, the most frequently detected phosphosite in TAOK1, as a significant regulatory phosphosite involved in the maintenance of genome integrity. Considering that the impact of all phosphosites that predominantly represent each kinase is essential for the efficient interpretation of global phosphoproteome datasets, we believe that the approach undertaken in this study is suitable to be extended to other kinases for accelerated research.
PMID:38479581 | DOI:10.1016/j.biocel.2024.106558