SAMHD1 shapes deoxynucleotide triphosphate homeostasis by interconnecting the depletion and biosynthesis of different dNTPs.

SAMHD1 is a dNTPase that impedes replication of HIV-1 in myeloid cells and resting T lymphocytes. Here we elucidate the substrate activation mechanism of SAMHD1, which involves dNTP binding at allosteric sites and transient tetramerization. Our findings reveal that tetramerization alone is insufficient to promote dNTP hydrolysis; instead, the activation mechanism requires an inactive tetrameric intermediate with partially occupied allosteric sites.

Soil Nitrogen Supply Exerts Largest Influence on Leaf Nitrogen in Environments with the Greatest Leaf Nitrogen Demand.

Accurately representing the relationships between nitrogen supply and photosynthesis is crucial for reliably predicting carbon-nitrogen cycle coupling in Earth System Models (ESMs). Most ESMs assume positive correlations amongst soil nitrogen supply, leaf nitrogen content, and photosynthetic capacity. However, leaf photosynthetic nitrogen demand may influence the leaf nitrogen response to soil nitrogen supply; thus, responses to nitrogen supply are expected to be the largest in environments where demand is the greatest.

Advances in the understanding and therapeutic manipulation of cancer immune responsiveness: a Society for Immunotherapy of Cancer (SITC) review.

Cancer immunotherapy-including immune checkpoint inhibition (ICI) and adoptive cell therapy (ACT)-has become a standard, potentially curative treatment for a subset of advanced solid and liquid tumors. However, most patients with cancer do not benefit from the rapidly evolving improvements in the understanding of principal mechanisms determining cancer immune responsiveness (CIR); including patient-specific genetically determined and acquired factors, as well as intrinsic cancer cell biology. Though CIR is multifactorial, fundamental concepts are emerging that should be considered for the design of novel therapeutic strategies and related clinical studies.

Different social experiences drive the development of divergent stress coping styles in female swordtails (Xiphophorus nigrensis).

Individual variation in stress coping styles is widespread and consequential to health and fitness. Proactive (bold behavior, low stress reactivity, low cognitive flexibility) and reactive (shy behavior, high stress reactivity, high cognitive flexibility) coping styles are found in many species, but the developmental forces shaping them remain elusive. We examined how social influences, specifically mating interactions, shape the development of adult female coping styles with a manipulative rearing experiment using El Abra swordtails, Xiphophorus nigrensis.

Collagen turnover during cervical remodeling involves both intracellular and extracellular collagen degradation pathways.

Reproductive success requires accurately timed remodeling of the cervix to orchestrate the maintenance of pregnancy, the process of labor, and birth. Prior work in mice established that a combination of continuous turnover of fibrillar collagen and reduced formation of collagen cross-links allows for the gradual increase in tissue compliance and delivery of the fetus during labor. However, the mechanism for continuous collagen degradation to ensure turnover during cervical remodeling is still unknown.

Design and validation of cell-based potency assays for frataxin supplementation treatments.

Friedreich's ataxia (FRDA) is a multisystem, autosomal recessive disorder caused by mutations in the frataxin () gene. As FRDA is considered an FXN deficiency disorder, numerous therapeutic approaches in development or clinical trials aim to supplement FXN or restore endogenous expression. These include gene therapy, protein supplementation, genome editing or upregulation of transcription.

Delivering Guideline-Concordant Care for Patients With High-Risk HPV and Normal Cytologic Findings.

Importance: As US health care systems shift to human papillomavirus (HPV)-based cervical cancer screening, more patients are receiving positive high-risk non-16/18 genotype HPV results and negative for intraepithelial lesion or malignancy (NILM) cytological findings. Risk-based management guidelines recommend 2 consecutive negative annual results to return to routine screening.

Objective: To quantify patterns of surveillance testing and associated outcomes for patients after an HPV-positive results and NILM cytologic findings.

Mercury toxicity resulting from enzyme alterations- minireview.

Mercury is widely known for its detrimental effects on living organisms, whether in its elemental or bonded states. Recent comparative studies have shed light on the biochemical implications of mercury ingestion, both in low, persistent concentrations and in elevated acute dosages. Studies have presented models that elucidate how mercury disrupts healthy cells.

A Lambda-evo (λ) phage platform for Zika virus E protein display.

One of the most significant bacteriophage technologies is phage display, in which heterologous peptides are exhibited on the virion surface. This work describes the display of λ decorative protein D linked to the E protein domain III of Zika virus (D-ZE), to the GFP protein (D-GFP), or to different domain III epitopes of the E protein (D-TD), exhibited on the surface of an in vitro evolved lambda phage (λ). This phage harbors a gene D deletion and was subjected to directed evolution using Escherichia coli W3110/pD-ZE as background.

Functional test of a naturally occurred tumor modifier gene provides insights to melanoma development.

Occurrence of degenerative interactions is thought to serve as a mechanism underlying hybrid unfitness in most animal systems. However, the molecular mechanisms underpinning the genetic interaction and how they contribute to overall hybrid incompatibilities are limited to only a handful of examples. A vertebrate model organism, Xiphophorus, is used to study hybrid dysfunction, and it has been shown from this model that diseases, such as melanoma, can occur in certain interspecies hybrids.

Climate change and the cost-of-living squeeze in desert lizards.

Climate warming can induce a cost-of-living "squeeze" in ectotherms by increasing energetic expenditures while reducing foraging gains. We used biophysical models (validated by 2685 field observations) to test this hypothesis for 10 ecologically diverse lizards in African and Australian deserts. Historical warming (1950-2020) has been more intense in Africa than in Australia, translating to an energetic squeeze for African diurnal species.

Mangrove-based carbon market projects: What stakeholders need to address during pre-feasibility assessment.

Mangrove-based carbon market projects (MbCMP) aim to conserve, protect and restore mangrove habitats in order to generate high quality blue carbon credits via a crediting program, as a contribution to climate change mitigation/adaptation, biodiversity conservation, ecosystem services provision and local socio-economic development. The blue carbon credits generated are transferable, verifiable and sold through carbon markets to earn additional income for governments and local communities. The main aim of the paper is to provide important considerations for pre-field planning, that is, how challenges associated with fieldwork, project implementation, and monitoring reporting and verification (MRV) can be addressed with proper pre-field planning.

Peptide nucleic acids: Recent advancements and future opportunities in biomedical applications.

Peptide nucleic acids (PNA), synthetic molecules comprising a peptide-like backbone and natural and unnatural nucleobases, have garnered significant attention for their potential applications in gene editing and other biomedical fields. The unique properties of PNA, particularly enhanced stability/specificity/affinity towards targeted DNA and RNA sequences, achieved significant attention recently for gene silencing, gene correction, antisense therapy, drug delivery, biosensing and other various diagnostic aspects. This review explores the structure, properties, and potential of PNA in transforming genetic engineering including potent biomedical challenges.

Macrolide resistance due to (55).

Unlabelled: Antimicrobial resistance (AMR) is a global threat. The identification and characterization of novel resistance genes is integral to AMR surveillance. The (55) gene was originally identified through whole genome sequencing of macrolide-resistant strains of .

Fluoroquinolones and rifampin combination in the backdrop of heteroresistant tuberculosis.

The impact of heteroresistance on tuberculosis (TB) treatment outcomes is unclear, as is the role of different rifampin and isoniazid exposures on developing resistance mutations. Hollow fiber system model of TB (HFS-TB) units were inoculated with drug-susceptible () and treated with isoniazid and rifampin exposure identified in a clinical trial as leading to treatment failure and acquired drug resistance. Systems were sampled for drug concentration measurements, estimation of total and drug-resistant , and small molecule overlapping reads (SMOR) analysis for the detection of heteroresistance.

colonization is not mediated by bile salts and utilizes Stickland fermentation of proline in an model.

Treatment with antibiotics is a major risk factor for infection, likely due to depletion of the gastrointestinal microbiota. Two microbiota-mediated mechanisms thought to limit colonization include the conversion of conjugated primary bile salts into secondary bile salts toxic to growth and competition between the microbiota and for limiting nutrients. Using a continuous flow model that simulates the nutrient conditions of the distal colon, we investigated how treatment with 6 clinically used antibiotics influenced susceptibility to infection in 12 different microbial communities cultivated from healthy individuals.

A case for broadening our view of mechanism in developmental biology.

Developmental biologists can perform studies that describe a phenomenon (descriptive work) and/or explain how the phenomenon works (mechanistic work). There is a prevalent perception that molecular/genetic explanations achieved via perturbations of gene function are the primary means of advancing mechanistic knowledge. We believe this to be a limited perspective, one that does not effectively represent the breadth of work in our field.

Reevaluating Anti-Inflammatory Therapy: Targeting Senescence to Balance Anti-Cancer Efficacy and Vascular Disease.

Modulating immune function is a critical strategy in cancer and atherosclerosis treatments. For cancer, boosting or maintaining the immune system is crucial to prevent tumor growth. However, in vascular disease, mitigating immune responses can decrease inflammation and slow atherosclerosis progression.

Oxidative Stress in Children and Adolescents: Insights Into Human Biology.

Oxidative stress (OS) is a key biological challenge and selective pressure for organisms with aerobic metabolism. The result of the imbalance between reactive oxygen species production and antioxidant defense, OS can damage proteins, lipids, and nucleic acids and plays an important role in driving variation in biological aging and health. Among humans, OS research has focused overwhelmingly on adults, with demonstrated connections between OS, inflammation, and metabolic and neurodegenerative conditions.

Resolving tissue complexity by multimodal spatial omics modeling with MISO.

Spatial molecular profiling has provided biomedical researchers valuable opportunities to better understand the relationship between cellular localization and tissue function. Effectively modeling multimodal spatial omics data is crucial for understanding tissue complexity and underlying biology. Furthermore, improvements in spatial resolution have led to the advent of technologies that can generate spatial molecular data with subcellular resolution, requiring the development of computationally efficient methods that can handle the resulting large-scale datasets.

The microcephaly-associated transcriptional regulator AUTS2 cooperates with Polycomb complex PRC2 to produce upper-layer neurons in mice.

AUTS2 syndrome is characterized by intellectual disability and microcephaly, and is often associated with autism spectrum disorder, but the underlying mechanisms, particularly concerning microcephaly, remain incompletely understood. Here, we analyze mice mutated for the transcriptional regulator AUTS2, which recapitulate microcephaly. Their brains exhibit reduced division of intermediate progenitor cells (IPCs), leading to fewer neurons and decreased thickness in the upper-layer cortex.

Orthogonalized human protease control of secreted signals.

Synthetic circuits that regulate protein secretion in human cells could support cell-based therapies by enabling control over local environments. Although protein-level circuits enable such potential clinical applications, featuring orthogonality and compactness, their non-human origin poses a potential immunogenic risk. In this study, we developed Humanized Drug Induced Regulation of Engineered CyTokines (hDIRECT) as a platform to control cytokine activity exclusively using human-derived proteins.

Loss of correlated proteasomal subunit expression selectively promotes the 20S state which underlies luminal breast tumorigenicity.

Why cancer cells disproportionately accumulate polyubiquitinated proteotoxic proteins despite high proteasomal activity is an outstanding question. While mis-regulated ubiquitination is a contributing factor, here we show that a structurally-perturbed and sub-optimally functioning proteasome is at the core of altered proteostasis in tumors. By integrating the gene coexpression signatures of proteasomal subunits in breast cancer (BrCa) patient tissues with the atomistic details of 26S holocomplex, we find that the transcriptional deregulation induced-stoichiometric imbalances perpetuate with disease severity.

IL-33-activated ILC2s induce tertiary lymphoid structures in pancreatic cancer.

Tertiary lymphoid structures (TLSs) are de novo ectopic lymphoid aggregates that regulate immunity in chronically inflamed tissues, including tumours. Although TLSs form due to inflammation-triggered activation of the lymphotoxin (LT)-LTβ receptor (LTβR) pathway, the inflammatory signals and cells that induce TLSs remain incompletely identified. Here we show that interleukin-33 (IL-33), the alarmin released by inflamed tissues, induces TLSs.