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Henry, C.

Publications and source records attributed to Henry, C..

At least 19 recordsLinked to original sources

Desmin p.R406W mutation is associated with arrhythmias through structural and electrophysiological remodeling

Background and AimsMutations in the desmin (DES) gene cause a variety of cardiomyopathies associated with arrhythmias, yet the electrophysiological consequences of these variants remain largely uncharacterized. The aim of this study was to investigate the pathogenic mechanisms of the de novo DES p.R406W variant, which was identified in a 9-year-old patient who suffered from severe ventricular arrhythmias and sudden cardiac death without overt structural heart disease. MethodsHuman induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) carrying the DES p.R406W variant (including the patients line) were compared to isogenic controls. Action potentials (AP) of hiPSC-CMs were recorded using patch-clamp. Furthermore, 3D engineered heart tissues (EHTs) were generated from hiPSC-CMs and their APs were recorded with sharp microelectrodes. Analytical techniques also included transmission electron microscopy (TEM) and integrated transcriptomic and proteomic profiling. Finally, a heterozygous knock-in (KI) mouse model carrying the Des p.R405W ortholog was evaluated through surface ECG, echocardiography and ex vivo cardiac optical mapping. ResultsThe DES p.R406W mutation prolonged AP duration in IM-R406W hiPSC-CMs and EHTs vs Control ones. Multi-omics analysis of EHTs revealed a dysregulation of genes and proteins involved in contractile function, cell adhesion, and electrical activity. TEM imaging revealed changes in Z-disc architecture in mutant tissues. Twenty-week-old Des p.R405W KI mice exhibited ventricular conduction slowing (prolonged QRS) and a high susceptibility to ventricular tachyarrhythmias, likely due to reentrant mechanisms. Mild hypertrophy was also observed, but only in females. ConclusionThe DES p.R406W variant is highly pathogenic, causing electrical and structural remodeling of the myocardium. This study highlights the effectiveness of hiPSC-CMs and EHTs in recapitulating the clinical phenotype of desminopathy, providing a platform for investigating the mechanisms of early-onset cardiac arrhythmias and SCD.

pathology↗

KBase Research Agent: Automated Multi-Agent Workflow Construction for Reproducible Genome Analysis

Constructing multi-step bioinformatics workflows, from read quality control through genome assembly to functional annotation, requires expertise in both biology and computational tool selection, creating a bottleneck for scalable and reproducible analysis. We present the KBase Research Agent, a multi-agent system for automating such workflows within the DOE Systems Biology Knowledgebase (KBase). Given a set of sequencing reads and a research objective, the agent constructs an analysis plan grounded in KBase documentation and a Knowledge Graph (KG) of the KBase application catalog, then selects, parameterizes, validates and executes appropriate KBase applications to carry out the workflow. The resulting analysis is preserved as a reproducible KBase Narrative. We evaluate the systems planning and execution quality against ground truth constructed from reference workflows derived from peer-reviewed Microbiology Resource Announcements. We further apply the agent to 100 previously unanalyzed bacterial isolate genomes from the JGI IMG/M database, where it autonomously performed read quality control, genome assembly, taxonomic classification with GTDB-Tk, and downstream analysis producing annotated genomes, reproducible Narratives, and draft manuscripts without human intervention. Across these experiments, the KBase Research Agent demonstrates the feasibility of domain-grounded, end-to-end scientific workflow automation in a production bioinformatics platform.

bioinformatics↗

Testosterone alleviates inflammation but increases the methacholine response in mice with allergic lung inflammation

Testosterone seems protective against asthma, but the underlying mechanisms are uncertain. Herein, the effect of testosterone was investigated on several features of experimental asthma. Systemic testosterone was first altered to subphysiological, physiological, or supraphysiological levels in male BALB/c mice through orchiectomy and testosterone supplementation. Testosterone (0.25 mg/day/30 g of body weight) was delivered continuously during 20 days using an implanted pump. At day 10, each group was exposed intranasally to either saline or house dust mite (HDM) once daily for 10 consecutive days to induce allergic lung inflammation. The day after the last exposure, respiratory mechanics was measured at baseline and in response to nebulized methacholine. Bronchoalveolar lavages (BAL) and lung tissues were also collected to quantify inflammation. Baseline respiratory mechanics were altered in mice with subphysiological levels of testosterone, with signs of small airway narrowing heterogeneity and closure. Testosterone drastically inhibited the HDM-induced inflammation. Yet, testosterone also increased the response to methacholine, as well as hysteresis, which are both indicators of enhanced airway smooth muscle activity. While it suggests that testosterone increases the contractility of the smooth muscle, it simultaneously and markedly inhibits inflammation. Explanations as to how these outcomes may lead to protection in asthma are discussed.

physiology↗

A single methylation site regulates HRSV nucleocapsid architecture and replication

The nucleoprotein N of the human respiratory syncytial virus (HRSV) encases the viral genome, forming a flexible N-RNA nucleocapsid helix that serves as template for the viral polymerase L. Recent structural analysis revealed a non-canonical helical nucleocapsid arrangement that modulates RNA accessibility, yet its impact on polymerase function remains unknown. Here, we identified symmetric dimethylation of residue R27 of N as a critical modulator of nucleocapsid architecture and viral replication. We also showed that the methylase PRMT5 interacts with N and likely catalyses R27 methylation. Molecular dynamics simulations of RNA-free N dimers indicate that R27 methylation enhances opening and closing of the RNA-binding cavity, whereas a methylation-mimicking R27M substitution favours a closed state. Cryo-electron microscopy reveals a canonical, markedly straight R27M helix with increased rise and pitch. These findings demonstrate that post-translational modifications fine-tune interactions between N protomers, shaping nucleocapsid assembly, structure and dynamics, and thereby controlling HRSV replication.

microbiology↗

EGFR/TBK1-dependent mitochondrial quality control contributes to acquired resistance to temozolomide

Acquisition of secondary resistance to chemotherapy in cancer cells is an ill-characterized multi-step process. We conducted a non-supervised, global proteomic analysis of U251 glioma cells treated by temozolomide as they transit from drug-sensitive to tolerant and then resistant states. This unprecedented analysis revealed key mitochondrial evolutions throughout the process. Following an early stress substantiated by a transient peak of reactive oxygen species, mitochondrial quality control mechanisms enable emergence of the resistant population. We combined genome editing, targeted protein degradation via PROTAC, and pharmacologic inhibitors to investigate the mechanisms underlying stress resolution both at population and single cell scales (including microscopic evaluation and in-situ proximity ligation assays). These studies unravel a Src-activated EGFR and TBK1 axis that initiates autophagic recycling of mitochondria as a necessary step to the emergence of the resistant population.

cancer biology↗

Evaluating sequencing strategies for endometrial microbiome profiling in endometrial cancer: a comparative study of short- and long-read 16S rRNA approaches

BackgroundEndometrial cancer (EC) is the most common gynaecological malignancy globally, with rising incidence and notable disparities in outcomes. In New Zealand, EC rates have increased significantly, particularly among M[a]ori and Pacific women, who face higher risks of advanced disease and poorer outcomes. Microbial dysbiosis has been implicated in EC pathogenesis, but characterising the uterine microbiome is challenging due to low microbial biomass and high contamination risk. AimsThis study aimed to pilot a protocol that could inform the preparation of a larger cohort trial. Short-read Illumina MiSeq and long-read Oxford Nanopore Technologies (ONT) 16S rRNA gene sequencing were investigated to profile the uterine microbiome in people with EC. Methods and ResultsUterine and vaginal swabs were analysed to assess platform performance in terms of DNA recovery, sequencing success, diversity metrics, and taxonomic resolution. The impact of sample freezing or immediate lysis prior to DNA extraction was also evaluated. ONT sequencing provided enhanced species-level resolution and improved detection of low-abundance taxa but showed variable performance in low-yield samples. Freezing prior to cell DNA extraction modestly increased bacterial 16S copy numbers and improved community consistency. Contamination was a problem across both platforms, particularly in low-biomass samples, but can be minimised during data analysis. ConclusionThis study provides practical guidance for sequencing platform selection and sample handling in uterine microbiome research. Our findings support future efforts to elucidate microbial contributions to EC pathogenesis and highlight the importance of rigorous contamination control. Importantly, this is the first presentation of a New Zealand cohort and contributes valuable data from an underrepresented population and informs future research in diverse clinical settings.

cancer biology↗

The Kinase CK1α coordinates Initiation and Termination of the cGAS-STING Pathway

The cGAS-STING pathway is an evolutionarily conserved antimicrobial defense mechanism that senses cytosolic DNA to trigger innate immune responses. cGAS and STING play dual roles in tumorigenesis, promoting antitumor immunity and cell death while fueling tumor growth and metastasis. However, the mechanisms fine-tuning this pathway remain elusive. Using proteomic approaches, we report that Casein Kinase 1 alpha (CK1) operates as a bimodal regulator of the cGAS-STING pathway. CK1 supports optimal DNA sensing by preventing the proteasomal degradation of cGAS driven by the cullin-RING ubiquitin ligase 3 (CRL3). Conversely, CK1 facilitates STING degradation and signaling termination in response to STING agonists, tempering IRF3 activation. Exploiting these counterposing functions, we show that selective degradation of CK1 with molecular-glue degraders impaired the survival of a triple-negative breast cancer cell line with chronic cGAS-STING activation and synergized with a STING agonist to kill acute myeloid leukemia cells. Thus, CK1s dual regulatory role in the cGAS-STING pathway presents a promising target for therapeutic development. TEASERThis study unveils CK1 as a bimodal regulator of the cGAS-STING pathway.

immunology↗

CDKN1A (p21Cip/Waf1) stabilizes Cyclin D3 by inhibiting its phosphorylation-dependent nuclear export following butyrate treatment

Butyrate-mediated inhibition of cell proliferation is part of the preventive role of dietary fiber against colorectal cancer (CRC). This effect notably involves the cyclin-dependent kinase inhibitor CDKN1A (p21Cip/Waf1) in human intestinal cells, yet the underlying molecular mechanisms remain incompletely understood. Previously, we observed a paradoxical increase in cyclin D3 (CCND3)--but not cyclin D1--levels upon butyrate exposure. Here, we demonstrate that the butyrate-induced accumulation of CCND3 protein results both from mRNA increase and a CDKN1A-dependent protein stabilization, specifically extending its nuclear half-life. Proteomic analyses of CCND3 co-immunoprecipitates identified complexes involving CDKN1A, CDK4, CDK6, and the CRC-associated kinase CDK5, particularly enriched in butyrate-treated cells. Phosphorylation at a conserved Thr residue, crucial for CCND nuclear export and subsequent proteasomal degradation, was notably reduced following butyrate treatment and inversely correlated with CDKN1A expression levels. Structural modeling based on AlphaFold2, complemented by molecular dynamics simulations, revealed possible differential interactions between CDKN1A and cyclins D1 and D3, predicting that CCND3-Thr283 becomes structurally buried upon CDKN1A binding, limiting its phosphorylation. Our findings provide novel mechanistic insights into how CDKN1A might regulate CCND3 stability, highlighting previously unexplored roles of cyclin D3-containing complexes in cell cycle arrest induced by butyrate.

cell biology↗

Kre6-Dependent β-1,6-glucan Biosynthesis Only Occurs in the Conidium of Aspergillus fumigatus

The structural role of {beta}-1,6-glucan has remained under-investigated in filamentous fungi compared to other fungal cell wall polymers, and previous studies have shown that the cell wall of the mycelium of A. fumigatus did not contain {beta}-1,6-glucans. In contrast, the current solid-state NMR investigations showed that the conidial cell wall contained a low amount of {beta}-1,6-glucan. ssNMR comparisons of the A. fumigatus and C. albicans {beta}-1,6-glucans showed they are structurally similar. Deletion of the KRE6 gene which is the only KRE gene in the A. fumigatus genome resulted in a mutant depleted of {beta}-1,6-glucan which has a growth phenotype similar to the parental strain. Even though it is not an essential polymer in A. fumigatus, {beta}-1,6-glucan play a role in cell wall organization since the kre6{Delta} mutant showed a higher sensitivity to Congo-red and Calcofluor white which are known to be general cell wall inhibitors. It is also another example of the significant structural differences seen between conidium and mycelium of filamentous fungi.

biochemistry↗

Distinct classes of 21 and 24-nt phasiRNAs suggest diverse mechanisms of biogenesis and function in rice anther development

PhasiRNAs (phased small interfering RNAs) are a major class of plant small RNAs known to be key regulators in male reproductive development of maize (Zea mays) and rice (Oryza sativa), among other plants. Earlier research focused primarily on premeiotic 21-nt phasiRNAs and meiotic 24-nt phasiRNAs, while new studies uncovered a premeiotic class of 24-nt phasiRNAs. The biogenesis and function of these phasiRNAs remain unclear. We conducted an integrative analysis combining small RNA (sRNA) sequencing and transcriptomic profiling of sRNA-associated genes across ten developmental stages of anther in Kitaake rice to map associations between sRNA-related genes and phasiRNA classes. We identified previously undescribed classes of postmeiotic 21-nucleotide (nt) and 24-nt phasiRNA-producing loci and characterized their unique accumulation patterns. Additionally, our findings reveal distinct nucleotide composition and register accumulation among the phasiRNA classes, suggesting the presence of diverse mechanisms of biogenesis and function. Our results provide new insights into the regulatory complexity of phasiRNAs, establishing a foundation for further functional studies and advancing our understanding of their roles in anther development and their underlying mechanisms. Plain Language SummarySmall RNAs play important roles in controlling how plants develop, but their function in plant reproduction is still not well understood. In rice, small RNAs called phasiRNAs help regulate how pollen develops, but past research has mostly focused on just two types: one found before meiosis and one found during meiosis. In this study, we analyzed small RNA activity across ten stages of rice anther development and found new phasiRNA-producing genes that are active after meiosis. We also discovered that different types of phasiRNAs have distinct patterns of accumulation and composition, suggesting that they have specialized roles in reproductive development. These findings reveal new layers of complexity in how small RNAs function and set the stage for future research to understand their exact roles in pollen formation. This work may help improve our understanding of plant fertility and contribute to advancements in crop breeding. Core ideasO_LIStage-specific accumulation patterns suggest more specialized functions of phasiRNAs. C_LIO_LIMeiotic 24-nt phasiRNAs are compositionally distinct from other 24-nt phasiRNAs. C_LIO_LINewly described phasiRNA clusters may differ in mechanism of biogenesis and function. C_LI

plant biology↗

Epigenetic small molecule screening identifies a new HDACi compound for ameliorating Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is the most common inherited muscle disease. There are currently few effective therapies to treat the disease, although many approaches are being pursued. Certain histone deacetylase inhibitors (HDACi) have been shown to ameliorate DMD phenotypes in mouse and zebrafish animal models, and the HDACi givinostat has recently gained FDA approval for DMD. Our goal was to identify additional HDACi, or other classes of epigenetic small molecules, that are beneficial for DMD. Using an established animal model for DMD, the zebrafish dmd mutant strain sapje, we screened a library of over 800 epigenetic small molecules of various classes. We used a quantitative muscle birefringence assay to assess and compare the effects of these small molecule treatments on dmd mutant zebrafish skeletal muscle. Our screening identified a new HDACi, SR-4370, that ameliorated dmd mutant zebrafish skeletal muscle degeneration, in addition to HDACi previously shown to improve dmd zebrafish. We find that a single early treatment of HDACi can ameliorate dmd zebrafish. Furthermore, we find that HDACi that improve dmd muscle also cause increased histone acetylation in zebrafish larvae, whereas givinostat does not appear to increase histone acetylation or improve zebrafish dmd muscle. Our results add to the growing evidence that HDACi are promising candidates for treating DMD. Our study also provides further support for the effectiveness of small-molecule screening in dmd zebrafish. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=101 SRC="FIGDIR/small/634796v1_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@1f9f54aorg.highwire.dtl.DTLVardef@15707bborg.highwire.dtl.DTLVardef@bcafb5org.highwire.dtl.DTLVardef@1b3a8f7_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗

Integration of mathematical modeling and economics approaches to evaluate strategies for control of Salmonella Dublin in a heifer-raising operation

Salmonella Dublin infections in heifer-raising operations (HROs) cause animal health and economic losses for these operations and represent a pathogen source for dairy farms obtaining replacement heifers from HROs. To improve control of S. Dublin, we (i) developed a mathematical model of S. Dublin transmission on a HRO, (ii) evaluated the vaccine effectiveness and cleaning improvements for controlling the infection, and (iii) evaluated the influence of infection and control strategies on the HROs operating income. We developed a modified Susceptible-Infected-Recovered-Susceptible model of S. Dublin spread in a batch-stocking HRO post-introduction of an index case, with stochasticity introduced through Monte Carlo simulations. Epidemiological outcomes (S. Dublin-induced deaths and abortions during raising and S. Dublin carriers and asymptomatic infections among raised replacement heifers) and operating income per 100-head raised on a HRO over a 2-year simulation were compared between control scenarios. We validated our model against S. Dublin infection data in cattle. Partial rank correlation coefficient and classification trees were used to determine parameter influence on model outcomes. Our model predicts a median of 37 carriers and 92 asymptomatic infections among raised replacement heifers out of 2,330 heifers that departed the operation by the end of the 2-year simulation period, highlighting the critical role of HROs in spreading S. Dublin. Increasing barn floor cleaning frequency (to a maximum of 12x per day) meaningfully reduced the S. Dublin epidemiological outcomes and improved the HROs operating income. Depending on the cost of cleaning, the median operating income increased between 1.2% to 10.6% in the first year when cleaning 12x per day compared to baseline (cleaning 1x per week). In most cost scenarios, predictions do not support the use of vaccination, even when paired with stringent cleaning measures. The developed model is expected to aid efforts to control S. Dublin in HROs.

ecology↗

Airway smooth muscle tone curbs hyperresponsiveness in experimental asthma

Background & ObjectivesA sustained contraction of airway smooth muscle, hereinafter called tone, increases the response to methacholine in healthy mice and humans. However, the effect of tone in the context of an active inflammation remains to be investigated. The objective of the present study was to test the effect of tone on the in vivo response to methacholine in mice during an active inflammatory phase of experimental asthma. MethodsMale BALB/c mice were exposed once-daily to either intranasal saline or house dust mite for 10 consecutive days to induce experimental asthma. They then underwent one of two methacholine challenges 24 h after the last exposure. While the same cumulative dose was administered in both challenges, one was preceded by a 20-min period of tone induced by nebulizing low doses of methacholine at 5-min intervals. Respiratory mechanics were monitored before and throughout the methacholine challenge by oscillometry. Bronchoalveolar lavages (BAL) and histology were also performed. ResultsBAL inflammation and histological alterations were consistent with experimental asthma. In accordance with previous studies, tone potentiated the response to methacholine in control mice, mainly by stiffening the lung periphery. The lung was even stiffer upon methacholine challenge during an active phase of inflammation in mice with experimental asthma, but this was not further potentiated by tone. In fact, in mice with experimental asthma, tone mitigated hyperresponsiveness by preventing further airway narrowing and, more importantly, small airway narrowing heterogeneity and closure. ConclusionDuring an active inflammatory phase of experimental asthma, tone protects against hyperresponsiveness. Take-home messageThe effect of airway smooth muscle tone on the methacholine response was investigated in mice with or without experimental asthma. While tone potentiated the methacholine response in control mice, it mitigated hyperresponsiveness in experimental asthma. These results unveiled a protective role of the airway smooth muscle in experimental asthma.

physiology↗

The ANKS3/BICC1 protein complex is a master post-transcriptional regulator of NPHP1 ciliopathy gene transcripts

Ciliopathies are a class of multi-systemic genetic diseases characterized by ciliary dysfunction. Here, we report a novel ANKS3 variant in patients with a renal ciliopathy known as nephronophthisis (NPH) associated with hepatic defects. ANKS3 is an ankyrin and sterile alpha motif domain-containing protein that interacts with many NPH proteins as well as with BICC1, an RNA-binding protein involved in renal cystic diseases. The pathogenic effect of the ANKS3 mutation was validated in the zebrafish mutant and knock-in rat model, the latter showing urine concentration defect and tubular dilatations similar to NPH patients. In addition, cilia morphology and function as well as epithelialization of kidney tubular cells was affected by loss or mutation of ANKS3. Finally, our results evidenced that these classically renal ciliopathy-associated phenotypes were linked to the negative regulation of BICC1 by ANKS3 which binds to transcripts of the major NPH gene NPHP1 and mediates their decay through the AGO2-RISC complex and recruitment into P-bodies. Altogether, our findings suggest that the ANKS3/BICC1 complex is a key post-transcriptional regulator of NPHP1 transcript stability, providing another level of regulation of cilium biogenesis and kidney homeostasis, as well as an unusual mechanism leading to NPH-related ciliopathies.

pathology↗

A widespread family of ribosomal peptide metallophores involved in bacterial adaptation to copper stress

Ribosomally synthesized and post-translationally modified peptides (RiPPs) are a structurally diverse group of natural products that bacteria employ in their survival strategies. Herein, we characterized the structure, the biosynthetic pathway and the mode of action of a new RiPP family called bufferins. With thousands of homologous biosynthetic gene clusters throughout the eubacterial phylogenetic tree, bufferins form by far the largest family of RiPPs modified by multinuclear non-heme iron-dependent oxidases (MNIO, DUF692 family). Using Caulobacter vibrioides bufferins as a model, we showed that the conserved Cys residues of their precursors are transformed into 5-thiooxazoles, further expanding the reaction range of MNIO enzymes. This rare modification is installed in conjunction with a partner protein of the DUF2063 family. Bufferin precursors are the first examples of bacterial RiPPs found to feature an N-terminal Sec signal peptide and thus to be exported by the ubiquitous Sec pathway, a new paradigm in the RiPP field. Other original features of bufferins are their large size and protein-like fold, which blurs the line between modified peptides and proteins. We reveal that bufferins are involved in copper homeostasis, and their metal-binding propensity requires the thiooxazole heterocycles. Bufferins enhance bacterial growth under copper stress by sequestering excess metal ions in the periplasm. Our study thus describes a large family of RiPP metallophores and unveils a widespread but overlooked metal homeostasis mechanism in eubacteria likely to be relevant to One-Health strategies. Significance statementCopper is both essential and toxic in excess. Bacteria face copper in their environments, notably in phagocytes, hence they have developed several defense mechanisms. We discovered a widespread strategy of protection from copper, through the biosynthesis of natural products that we call bufferins. Bufferins are ribosomally synthesized post-translationally modified peptides (RiPPs), natural products with key roles in bacterial physiology and ecology. Bufferins enhance bacterial growth under copper stress by complexing with the metal using thiooxazole heterocycles that result from enzymatic modification of cysteine residues. With thousands of homologs throughout the eubacterial phylogenetic tree, bufferins represent a highly prevalent strategy of adaptation to metal stress. They are larger in size than most RiPPs, expanding the concept of RiPPs to modified proteins.

microbiology↗

Rendering the metabolic wiring powering wetland soil methane production

Accounting for only 8% of Earths land coverage, freshwater wetlands remain the foremost contributor to global methane emissions. Yet the microorganisms and processes underlying methane emissions from wetland soils remain poorly understood. Over a five-year period, we surveyed the microbial membership and in situ methane measurements from over 700 samples in one of the most prolific methane-emitting wetlands in the United States. We constructed a catalog of 2,502 metagenome-assembled genomes (MAGs), with more than half of the 70 bacterial and archaeal phyla sampled containing novel lineages. Integration of these data with 133 soil metatranscriptomes provided a genome-resolved view of the biogeochemical specialization and versatility expressed over wetland soil spatial and temporal gradients. Centimeter-scale depth differences best explained patterns of microbial community structure and transcribed functionalities, even more so than land coverage or temporal information. Moreover, while extended flooding restructured soil redox, this perturbation failed to reconfigure the transcriptional profiles of methane cycling microorganisms, contrasting with theoretical expected responses to hydrological perturbations. Co-expression analyses coupled to depth resolved methane measurements exposed the metabolisms and trophic structures most predictive of methane hotspots. Mapping the spatiotemporal transcriptional patterns on this compendium of biogeochemically classified soil derived genomes begins to untangle the microbial carbon, energy, and nutrient processing contributing to wetland methane production. ImportanceSoil microbial ecology is increasingly recognized as essential to climate mitigation, but realizing its full potential requires shifting from static genome inventories to dynamic assessments of microbial activity. This study shows that methane-cycling microbes exhibit stable, depth-stratified expression patterns, even in response to major redox and flooding shifts, undermining assumptions that water-table manipulations common in wetland management can alone reduce methanogenesis. Instead, methane cycling is shaped by spatially organized, transcriptionally active networks involving not only methanogens but also methanotrophs, fermenters, and iron reducers. These findings expose the limitations of genome-only models and highlight the need for soil diagnostics that capture in situ activity. Together, we provide a foundation for developing activity-based microbiome tools, embedding microbial functions into Earth system models, and designing interventions that move beyond "single lever" strategies and instead work with the structure and dynamics of microbial communities as complex, layered systems.

microbiology↗

The YARS Tyrosyl tRNA Synthetase Regulates Senescence Induction and Escape Through the Transcriptional Control of LIN9, a Member of the DREAM Complex

Senescence is a tumor suppressor mechanism triggered by oncogene expression and chemotherapy treatment. It orchestrates a definitive cessation of cell proliferation through the activation of the p53-p21 and p16-Rb pathways, coupled with the compaction of proliferative genes within heterochromatin regions. Some cancer cells have the ability to elude this proliferative arrest but the signaling pathways involved in circumventing senescence remain to be characterized. We have recently described that malignant cells capable of evading senescence have an increased expression of specific tRNAs, such as tRNA-Leu-CAA and tRNA-Tyr-GTA, alongside the activation of their corresponding tRNA ligases, namely LARS and YARS. We have previously shown that YARS promotes senescence escape by activating proliferation and cell cycle genes but its functions during this proliferative arrest remain largely unknown. In this study, we have continued to characterize the functions of YARS, describing non-canonical transcriptional functions of the ligase. Our results show that YARS is present in the nucleus of growing and senescent cells and interacts with the Trim28 transcriptional regulator. Importantly, YARS binds to the LIN9 promoter, a critical member of the Dream complex responsible for regulating cell cycle transcription. YARS facilitates the binding and the phosphorylation of the type II RNA polymerase and promotes the deposit of activating epigenetic marks on the LIN9 promoter. Consequently, during senescence escape, YARS promotes LIN9 expression and both proteins are necessary to induce the proliferation of emergent cells. These results underscore the unconventional transcriptional functions of YARS in promoting senescence escape by activating LIN9 and likely influencing the functions of the Dream complex.

cancer biology↗

A Molecular Communication model for cellular metabolism

Understanding cellular engagement with its environment is essential to control and monitor metabolism. Molecular Communication theory (MC) offers a computational means to identify environmental perturbations that direct or signify cellular behaviors by quantifying the information about a molecular environment that is transmitted through a metabolic system. We developed an model that integrates conventional flux balance analysis metabolic modeling (FBA) and MC to mechanistically expand the scope of MC, and thereby uniquely blends mechanistic biology and information theory to understand how substrate consumption is captured reaction activity, metabolite excretion, and biomass growth. This is enabled by defining several channels through which environmental information transmits in a metabolic network. The information flow in bits that is calculated through this workflow further determines the maximal metabolic effect of environmental perturbations on cellular metabolism and behaviors, since FBA simulates maximal efficiency of the metabolic system. We exemplify this method on two intestinal symbionts - Bacteroides thetaiotaomicron and Methanobrevibacter smithii - and visually consolidated the results into constellation diagrams that facilitate interpretation of information flow from given environments and thereby cultivate the design of controllable biological systems. The unique confluence of metabolic modeling and information theory in this model advances basic understanding of cellular metabolism and has applied value for the Internet of Bio-Nano Things, synthetic biology, microbial ecology, and autonomous laboratories.

bioinformatics↗