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PubMed2026

Exploring precision risk in pediatric vesicoureteral reflux: Innate immune gene variations and reflux outcomes in the RIVUR cohort.

INTRODUCTION: Children with vesicoureteral reflux (VUR) are at increased risk for morbidity from recurrent urinary tract infections (UTIs), yet the factors influencing spontaneous VUR resolution remain poorly defined. This study evaluates whether genetic variations in key urinary innate immune effectors (DEFA1A3, DMBT1, and RNASE7) influences VUR resolution and interacts with prophylaxis to alter clinical response. METHODS: We conducted a secondary analysis of 303 RIVUR participants with available DEFA1A3 and DMBT1 copy number variation (CNV) data and RNASE7 rs1263872 genotype. Primary outcomes were (1) VUR improvement (decrease in grade) and (2) VUR resolution at study exit. Multivariable logistic regression models included genotype, treatment, and their interactions, adjusting for age, sex, baseline grade (high vs low), laterality, bowel/bladder dysfunction, and any UTI. Internal validation used 2000-sample bootstrap with bias-corrected and accelerated confidence intervals and influence diagnostics. RESULTS: Clinical covariates did not significantly predict VUR improvement. Children with DEFA1A3 CNV >5 had higher odds of improvement (OR 2.36, 95% CI 1.12-4.96, p = 0.023), an effect that remained significant in bootstrap analyses. High-grade VUR was associated with lower odds of resolution (OR 0.34, 95% CI 0.12-0.94, p = 0.038). A significant interaction was observed between prophylaxis and high DMBT1 copy number for VUR resolution (interaction OR 2.99, 95% CI 1.11-8.04, p = 0.031); no interaction was seen for improvement. RNASE7 rs1263872 was not associated with either outcome. CONCLUSION: Innate immune gene variation may contribute to heterogeneity in VUR outcomes. High DEFA1A3 copy number was associated with reflux improvement and a DMBT1-prophylaxis interaction was associated with reflux resolution. The results of this study is hypothesis-generating and prompt further evaluation to assess whether a subset of children may experience structural benefit from prophylaxis or have a more favorable natural history based on their innate immune genotype.

Humans↗

PubMed2026

Osimertinib With or Without Chemotherapy in Advanced Non-Small Cell Lung Cancer With EGFR and Concurrent TP53 Mutations: A Randomized Clinical Trial.

IMPORTANCE: Combination therapy has emerged as a promising therapeutic approach for patients with epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC). However, its clinical benefit-risk profile remains a focus of ongoing debate. Identifying patients most likely to derive benefit from such regimens remains an unmet clinical need. OBJECTIVE: To prospectively compare the efficacy and safety of first-line osimertinib plus chemotherapy with osimertinib monotherapy for patients with EGFR-mutated advanced NSCLC harboring concurrent TP53 mutations. DESIGN, SETTING, AND PARTICIPANTS: A multicenter, randomized, open-label, phase 3 study conducted at 17 sites in China. Between March 25, 2021, and July 11, 2024, a total of 294 eligible patients with treatment-naive, stage IV or recurrent nonsquamous NSCLC harboring concurrent TP53 and EGFR-sensitizing mutations were enrolled. INTERVENTIONS: Patients were randomized (1:1) to receive osimertinib plus chemotherapy (pemetrexed and carboplatin every 3 weeks for 4 cycles, followed by maintenance therapy of osimertinib plus pemetrexed; n = 146) or osimertinib monotherapy (n = 148). MAIN OUTCOMES AND MEASURES: The primary end point was investigator-assessed progression-free survival. Secondary end points included overall survival, response, safety, and quality of life. RESULTS: Among 294 enrolled patients, the median age was 57 years (range, 26-79 years), and 159 (54.1%) were female. The data cutoff date was November 11, 2025. At a median follow-up of 25.1 months for the osimertinib-chemotherapy group and 26.1 months for the osimertinib monotherapy group, median progression-free survival was significantly longer with osimertinib plus chemotherapy than with osimertinib monotherapy (34.0 vs 15.6 months; difference, 18.4 months [95% CI, 9.9-22.3]; hazard ratio, 0.44 [95% CI, 0.32-0.60]; P < .001). This benefit was consistent across prespecified subgroups, including those with brain metastases and L858R mutations. The overall survival data remained immature (30.6% maturity); however, a trend toward overall survival benefit with combination therapy was observed. The incidence of grade 3 or higher treatment-related adverse events was higher in the combination group, with no new safety signal identified. CONCLUSIONS AND RELEVANCE: In this randomized clinical trial, osimertinib plus chemotherapy significantly increased progression-free survival among patients with EGFR-mutated advanced NSCLC harboring concurrent TP53 mutations. These findings provided a clinical rationale for individualized combination strategies in the management of patients with EGFR-mutated NSCLC. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04695925.

Adult↗

PubMed2026

In vitro evaluation of sacituzumab govitecan in non-small cell lung cancer with actionable genomic alterations.

PURPOSE: The TROP2-directed antibody-drug conjugate sacituzumab govitecan (SG) has shown substantial therapeutic benefit in several malignancies; however, preclinical evidence supporting its activity in non-small cell lung cancer (NSCLC) is rare. MATERIALS AND METHODS: We evaluated 16 NSCLC cell lines harboring actionable genomic alterations for TROP2 expression and treated them with SG or its unconjugated payload, SN-38, for 3 days to determine cytotoxic effects. Apoptosis and DNA damage signaling were assessed using flow cytometry and western blot. SG internalization and lysosomal trafficking were visualized by confocal microscopy. RESULTS: SG had greater cytotoxic potency than SN-38, across all NSCLC cell lines, independent of genomic subtype or TROP2 expression level. Cell lines that were sensitive to SN-38 showed enhanced vulnerability to SG (P < 0.0001). Higher SLFN11 expression, a recognized determinant of SN-38 responsiveness, correlated with lower SG IC50 values. Both SG and SN-38 triggered apoptotic and DNA damage responses within 6-48 h, with SG inducing stronger activation of these pathways than SN-38. SG was efficiently taken up in CUTO17 and SNU-3173 adenocarcinoma cells, with more than 60% of the conjugate internalized within 3 h and subsequently localized to lysosomes. CONCLUSION: Our study provides in vitro evidence supporting the potential activity of SG in NSCLC with actionable genomic alterations. The efficacy of SG closely paralleled intrinsic sensitivity to the SN-38 payload, suggesting that DNA-damage responses, rather than oncogenic drivers, predominantly contribute to SG activity.

Actionable genomic alterations↗

PubMed2026

Assessing time to symptomatic progression, a patient-relevant efficacy endpoint, in the MARIPOSA study in non-small cell lung cancer.

INTRODUCTION: In the phase 3 randomized MARIPOSA study, amivantamab and lazertinib combination therapy demonstrated improved progression-free survival (PFS) and overall survival (OS) versus osimertinib in participants with previously untreated, epidermal growth factor receptor-mutated advanced non-small cell lung cancer. Time to symptomatic progression (TTSP) was introduced to assess clinical worsening and complement endpoints that investigate radiographic disease progression and patient-reported outcomes. TTSP provides an easily interpretable measure of disease-specific symptom worsening to further support patient experience. METHODS: In MARIPOSA, TTSP was quantitatively assessed as a secondary efficacy endpoint and defined as the time from randomization until participants experience disease-specific symptom worsening requiring a clinical intervention or treatment change, or death. To evaluate the impact of amivantamab and lazertinib on TTSP considering its established OS benefit against osimertinib, an exploratory analysis censoring death events was performed. RESULTS: At the final protocol-specified OS analysis (median follow up: 37.8 months), median TTSP was 43.6 months with amivantamab and lazertinib versus 29.3 months with osimertinib (hazard ratio [HR]: 0.69; 95% confidence interval [CI]: 0.57-0.83; p < 0.0001). Amivantamab and lazertinib reduced deaths following a TTSP event compared to osimertinib. A strong correlation between TTSP and PFS or OS was observed. CONCLUSIONS: Amivantamab and lazertinib significantly delayed TTSP versus osimertinib. TTSP offers a clinician-validated measurement of disease-specific symptom worsening, capturing symptoms perceived by patients that prompt clinical action. TTSP is highly correlated with PFS and OS, providing complementary insights alongside traditional endpoints. TTSP enhances understanding of treatment benefit and supports informed clinical decision-making by integrating patient experience.

Humans↗

PubMed2026

Validation of the lung immune prognostic index in extensive-stage small cell lung cancer: Post hoc analysis of the caspian and IMpower133 phase 3 trials.

BACKGROUND: The Lung Immune Prognostic Index (LIPI) is an inflammation-based biomarker associated with outcomes to immunotherapy across several tumor types. Its prognostic value in extensive-stage small-cell lung cancer (ES-SCLC), however, remains insufficiently validated. We aimed to validate the prognostic impact of LIPI in ES-SCLC using data from two phase III trials. METHODS: Patients enrolled in the CASPIAN (NCT03043872) and IMpower133 (NCT02763579) trials were included. LIPI groups were defined as good (dNLR<3 and LDH<ULN), intermediate (dNLR≥3 or LDH≥ULN) and poor (dNLR≥3 and LDH≥ULN). Overall survival (OS) and progression-free survival (PFS) were assessed across LIPI categories and treatment arms. RESULTS: LIPI was available for 1140 patients (Good: 34%, Intermediate: 49%, Poor: 17%), including 708 treated with chemotherapy-immunotherapy and 432 with chemotherapy alone. Poor LIPI was associated with unfavorable characteristics, including lower albumin levels and higher rate of liver metastases. Median OS was 14.6 months (95%CI: 12.4-15.9) for LIPI Good, 10.9 (10.1-11.5) for Intermediate, and 8.4 (7.1-9.3) for Poor (p < 0.0001). In multivariate models adjusted on gender, age, ECOG, treatment arm and metastatic sites, LIPI remained an independent prognostic factor for OS (HR Poor vs. Good: 1.76, 95%CI: 1.45-2.15, p < 0.001) and PFS (HR: 1.59, 95%CI: 1.33-1.90, p < 0.001). Although patients with poor LIPI derived limited benefit from immunotherapy, no significant treatment-LIPI interaction was observed. CONCLUSION: This large post hoc analysis confirms LIPI as a robust and clinically applicable prognostic biomarker in ES-SCLC. Patients with poor LIPI have substantially worse outcomes and limited benefit from immunotherapy, highlighting the need for novel therapeutic strategies in this subgroup.

Humans↗

PubMed2026

Development and validation of an LC-MS/MS method for the quantification of the KRASG12C inhibitor divarasib.

Divarasib is a newly developed covalent KRASG12C inhibitor, currently under clinical investigation in a phase 3 trial in patients with non-small cell lung cancer (NSCLC). At the moment, very limited pharmacokinetic data are publicly known. However, obtaining more insight into the pharmacokinetic properties of divarasib is important, since this may provide a better understanding of its efficacy and safety risks. Pre-clinical studies have been performed in mouse models to evaluate the effect of drug transporters and drug-metabolizing enzymes on the plasma exposure and tissue distribution of divarasib. Therefore, a reliable quantification method is required. To our knowledge, no bioanalytical assay of divarasib has been published yet. Therefore, in this study we developed and validated an assay to quantify divarasib in human plasma and in eight different mouse-related matrices, and partially in mouse plasma, using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The method was initially evaluated over a concentration range of 1-10,000 nM. However, due to carry-over observed at 10,000 nM, the validated calibration range was established at 1-2000 nM, with matrix-dependent LLOQs of 1-10 nM. Erlotinib was used as an internal standard and acetonitrile was utilized to perform protein precipitation as sample pretreatment. Divarasib demonstrated stability in human plasma and in mouse plasma and tissue homogenates under various experimental conditions. A pilot in vivo study showed the applicability of our validated LC-MS/MS method. Ongoing clinical trials may collect plasma samples, and this developed method enables quantification of divarasib in both mouse and human plasma samples.

Animals↗

PubMed2026

Diagnostic utility of high-risk HPV polymerase chain reaction-based testing in head and neck FNA specimens with indeterminate cytomorphology.

BACKGROUND: Fine-needle aspiration (FNA) is critical in the initial diagnosis of many high-risk human papillomavirus (HR-HPV)-associated, metastatic oropharyngeal squamous cell carcinomas. Updated guidelines recommend HR-HPV-specific polymerase chain reaction (PCR) analysis over p16 immunohistochemistry on FNA specimens because p16 performs poorly on cytology material. PCR-based assays on liquid cytology material have demonstrated excellent analytic performance; however, the diagnostic utility of a positive HR-HPV PCR result in specimens with indeterminate cytomorphology remains uncharacterized. METHODS: The authors retrospectively identified 279 head and neck FNA specimens that had paired HR-HPV PCR testing on residual liquid cytology material over a 5-year period. The positive predictive value for histopathologically confirmed squamous cell carcinoma on surgical follow-up was calculated within each cytologic interpretive category. RESULTS: The HR-HPV PCR results were positive in 50.2% of specimens, negative in 40.9%, and indeterminate in 9.0%. The HR-HPV positivity rate ranged from 0% in specimens categorized as negative for malignancy to 57.3% in cytologically positive specimens, with 19.0%, 41.2%, and 50.0% positivity in the atypical, suspicious, and nondiagnostic categories, respectively. Among cytologically indeterminate specimens with positive HR-HPV PCR results (n = 14), the positive predictive value was 100% (95% confidence interval, 78.5%-100.0%). Blinded slide review additionally identified 15 cytologically positive specimens in which the definitive malignant interpretation depended substantially on HR-HPV positivity; all 15 were confirmed as squamous cell carcinoma. CONCLUSIONS: A positive HR-HPV PCR result on liquid cytology material carries a positive predictive value of 100% for malignancy in cytologically indeterminate head and neck FNA specimens. These findings support integrating HR-HPV PCR analysis into routine cytologic interpretation with the potential to upgrade some indeterminate specimens to malignant when HR-HPV is detected, expediting definitive treatment and sparing patients additional, invasive sampling.

Humans↗

PubMed2026

Distinct functions of mammalian RAD51 paralogs in genome maintenance.

RAD51 paralogs (RAD51B, RAD51C, RAD51D, XRCC2, and XRCC3) are evolutionarily conserved essential proteins for cell survival and genome maintenance. RAD51 paralogs were originally identified to play a role in homologous recombination-mediated repair of DNA double-strand breaks (DSBs). However, investigations over the last decade have uncovered new roles of RAD51 paralogs beyond DSB repair in replication stress responses, including replication fork progression, fork stability, and its restart. Recent structural studies have not only uncovered the molecular architecture of previously known RAD51 paralog complexes but also identified novel paralog complex assemblies, providing mechanistic insights into their various genome-maintenance functions. Additionally, a role for RAD51 paralogs in resolving R-loops has been identified, and studies with cancer-associated variants suggest that RAD51 paralogs are potential determinants of cancer susceptibility and therapeutic responses. In the present review, we highlight the recently deciphered structures and novel functions of RAD51 paralog complexes and discuss the clinical and therapeutic implications.

Rad51 Recombinase↗

PubMed2026

Secretory Phospholipase A2 in Patients With Sickle Cell Disease Hospitalized for Vaso-Occlusive Pain Episodes.

BACKGROUND: Secretory phospholipase A2 (sPLA2) is an inflammatory mediator linked to acute chest syndrome (ACS) in sickle cell disease (SCD), a serious complication that can develop during an acute vaso-occlusive pain episode (VOE). Plasma sPLA2 levels have been proposed as a potential biomarker for predicting ACS onset. OBJECTIVE: To assess serial plasma sPLA2 levels in 105 pediatric patients hospitalized for SCD-VOE and determine the effects of arginine therapy compared to placebo. PROCEDURES: This is a pharmacokinetics/pharmacodynamics and randomized controlled trial of intravenous arginine therapy. Statistical methods included t-tests, chi-square, and correlation analyses. RESULTS: Mean age was 12.7 ± 3.7 years, 48% were male, 67% had Hb-SS, and 70% were prescribed hydroxyurea. Using a previously established SCD-specific cutoff of 48 ng/mL, presenting sPLA2 levels were elevated in 33% of patients (mean sPLA2 level 85.7 ± 32.9 ng/mL). SPLA2 elevation in the emergency department was more common in patients with ACS compared to those without ACS (64% vs. 30%; p = 0.02; negative predictive value of 94%). Peak sPLA2 levels were significantly higher in febrile (n = 34) versus afebrile patients (n = 71;101.0 ± 45.3 vs. 48.7 ± 35.4 ng/mL; p < 0.0001). Among subjects with elevated baseline sPLA2, arginine therapy resulted in a significant reduction in sPLA2 levels by discharge compared to placebo (-27.8 ± 38.1 ng/mL; p = 0.002; n = 23 vs. -15.0 ± 41.2 ng/mL; p = 0.23; n = 12). CONCLUSIONS: SPLA2 is an underutilized biomarker of ACS given accumulating evidence of its role. In particular, low levels may identify patients at low risk for ACS. Arginine therapy may modulate inflammation in patients with SCD during VOE and/or ACS. TRIAL REGISTRATION: ClinicalTrials.gov identifiers: NCT02447874; NCT02536170.

Humans↗

PubMed2026

Beyond species trees: pervasive gene flow limits phylogenomic resolution in the diversification of Juniperus from the Qinghai-Tibet Plateau.

Understanding how lineages diversify despite persistent ancestral polymorphism and recurrent gene flow remains a central challenge in evolutionary biology. Juniperus distributed across the Qinghai-Tibet Plateau provide an ideal system for addressing this question because repeated geological uplift and climatic oscillations have likely promoted cycles of lineage divergence, range shifts, and secondary contact. Here, we combined approximately 1.08 million genome-wide SNPs from 164 individuals representing thirteen Juniperus lineages with phylogenomic datasets comprising 3,381 nuclear single-copy genes and nearly complete plastomes. We detected extensive phylogenomic discordance and cytonuclear incongruence across genomic datasets. Topology weighting, coalescent simulations, quartet-based tests, and analyses of gene flow and reticulation collectively support the interpretation that these patterns were shaped by the combined effects of prolonged incomplete lineage sorting and gene flow during lineage diversification. Ecological niche analyses further provide a spatial and climatic context in which environmentally similar lineages may have had greater opportunities for secondary contact during historical range shifts. Collectively, our results reveal that the evolutionary history of Qinghai-Tibet Plateau Juniperus is characterized by reticulate diversification rather than strictly bifurcating evolution, and demonstrate how genome-wide discordance can provide biological insights into the evolutionary processes underlying lineage diversification.

Gene Flow↗

PubMed2026

Genome-Wide Impact of Human DBR1 Depletion on RNA Processing Networks Reveal a Connection Between Pre-mRNA Splicing, mRNA Surveillance and Stress Granule Dynamics.

The RNA lariat debranching enzyme DBR1 is essential for intron turnover and RNA metabolism, yet its broader impact on transcriptome regulation remains incompletely defined. To elucidate the consequences of DBR1 depletion, we performed transcriptome-wide RNA sequencing of DBR1-knockdown and wild-type HEK293 cells. Differential expression analysis revealed widespread perturbations in pathways linked to RNA splicing, mRNA surveillance, translational control, and stress-granule biology. Many of the most significantly altered transcripts encode splicing factors and RNA quality-control components, underscoring DBR1's influence on post-transcriptional regulation. Alternative splicing analysis showed changes across multiple event types, with exon skipping accounting for >50% of events, followed by mutually exclusive exons, alternative 5' and 3' splice sites, and retained introns, indicating that DBR1 depletion induces pervasive splicing defects. Direct spliceosome inhibition using isoginkgetin (blocks tri-snRNP recruitment) and pladienolide B (targets SF3B1) reproduced the DBR1-KD mis-splicing patterns of cell signaling genes and factors involved in RNA metabolism, supporting a functional link between DBR1 activity and alternative splicing. Notably, DBR1 knockdown revealed a subset of transcripts that are both NMD-sensitive and enriched within stress granules. Consistent with this observation, G3BP1 immunopurification and confocal microscopy further support a role for DBR1 and UPF1 in stress-granule dynamics, suggesting that these factors may participate at distinct stages to influence mRNA fate under stress conditions. Together, these findings indicate that DBR1 functions beyond lariat RNA turnover as a common regulator of RNA processing, transcriptome stability, and stress granule homeostasis, revealing intricate crosstalk between RNA splicing and RNA quality control pathways in human cells.

Humans↗

PubMed2026

Dealcoholized muscadine wine improved skin elasticity and oxidative stress biomarkers without affecting gut microbiome in women over 40 in a randomized controlled trial.

Muscadine wine has a unique polyphenol profile distinct from that of common wine, and limited research exists on its health benefits. This study aimed to investigate the effects of intake of dealcoholized muscadine wine (DMW) on skin health, oxidative stress, inflammatory biomarkers, and the gut microbiome. Seventeen healthy women were randomly assigned to consume 300 mL of DMW or a placebo daily for 6 weeks, separated by a 3-week washout period, in a randomized, single-blinded, crossover design. Skin health parameters were measured on the face and forearm. Oxidative stress and inflammatory biomarkers were assessed in plasma. Fecal bacterial DNA was sequenced using shotgun sequencing. DMW did not affect UVB-induced erythema compared to placebo. However, it significantly decreased transepidermal water loss and increased facial gross elasticity. Skin elasticity significantly improved on the forearm, whereas other skin parameters were not affected. DMW significantly decreased plasma levels of matrix metalloproteinase-9 and advanced glycation end products compared with placebo. However, the abundance, diversity, and functions of the gut microbiome were not affected. Polyphenol-rich DMW administered for six weeks improved certain skin health parameters and reduced oxidative and inflammatory stress, without affecting the gut microbiome in healthy women.

Humans↗

PubMed2026

Ribosomal protein S3: a critical regulator of human disease mechanisms.

Ribosomal protein S3 (RPS3) is an essential structural component of the 40S ribosomal subunit, yet growing evidence highlights crucial extraribosomal roles in genome maintenance, cell-cycle control, and immune signaling. Dysregulation of RPS3 contributes to diverse human disorders, including cancer, inflammatory diseases, neurodegeneration, and resistance to antimicrobial and anticancer therapies. As a cofactor of NF-κB and a participant in DNA damage responses, RPS3 occupies a node that integrates stress signaling with transcriptional reprogramming, enabling both protective and pathological outcomes. The present review critically evaluates mechanistic insights into RPS3 biology, emphasizing recent findings that delineate its context-dependent effects, discrepancies across models, and remaining gaps that restrict translational applications. Understanding these complexities is essential to assess RPS3's potential as a biomarker and therapeutic target.

Humans↗

PubMed2026

An Update on Inborn Errors of V(D)J Recombination.

V(D)J recombination is the fundamental process by which developing T and B lymphocytes generate diverse antigen receptors, enabling adaptive immunity. This tightly regulated program operates exclusively in lymphoid precursors during G1 phase and depends on the lymphocyte-specific RAG1-RAG2 recombinase to introduce programmed DNA double-strand breaks at recombination signal sequences, followed by repair through the classical nonhomologous end joining (c-NHEJ) pathway. Disruption of any step in this molecular choreography compromises antigen receptor diversity and underlies a spectrum of inborn errors of immunity (IEIs), ranging from severe combined immunodeficiency (SCID) to immune dysregulation with autoimmunity and granulomatous disease. In this review, we place disorders of V(D)J recombination within the broader framework of T-cell development, detailing the temporal waves of recombinase activity, chromatin accessibility, and DNA damage responses that guide thymocyte differentiation. We discuss pathogenic variants affecting the cleavage phase [RAG1, RAG2, and the recently identified RAG cochaperone NudC domain-containing 3 (NUDCD3)], end processing (ARTEMIS), ligation and repair (LIG4, XLF, XRCC4, PRKDC), and genome surveillance pathways (ATM, MRN complex, RNF168), highlighting genotype-phenotype correlations and mechanisms driving immune deficiency and dysregulation. We briefly review recent diagnostic advances, including newborn screening using T-cell receptor excision circles, repertoire sequencing, and functional assays, alongside current therapeutic strategies. Finally, we outline key unanswered questions and argue that continued integration of clinical observation with molecular discovery is essential to improve outcomes and deepen understanding of adaptive immune development.

Humans↗

PubMed2026

Genome-wide insights into the evolutionary and demographic history of the red alga Mazzaella laminarioides: Evidence for speciation with ancient migration along the southeast Pacific coast.

The mechanisms driving lineage divergence in red algae remain unexplored, despite the group's remarkable diversity and ancient evolutionary history. The red alga Mazzaella laminarioides, a Chilean intertidal species complex composed of three parapatric cryptic lineages (North, Center, South), offers a valuable system to evaluate these processes, as its life history combines severe dispersal limitation with a haploid-diploid cycle that may influence the emergence of reproductive barriers. We reconstructed its evolutionary history using whole-genome sequencing and nuclear genome assembly of representative individuals from each lineage. Phylogenomic analyses based on 1,507 single-copy orthologs recovered three deeply divergent lineages with limited nuclear discordance consistent with incomplete lineage sorting. For both splits, demographic modelling was most consistent with an Ancient Migration scenario, although support over strict isolation was moderate, suggesting that divergence may have begun with low asymmetric ancestral gene flow followed by subsequent loss of connectivity, demographic bottlenecks, and later population expansion. Coding sequence analyses revealed lineage-specific dN/dS heterogeneity; only one South-lineage locus passed FDR correction (metaxin-1, mitochondrial protein import), with two further South-lineage candidates in chlorophyll and heme biosynthesis falling below the FDR threshold. Together, these signals suggest that divergent selective pressures on energy acquisition may have contributed to divergence at the southern end of the distribution. These results add to the small but growing body of whole-genome data for red algae and, alongside recent macroalgal studies, suggest that ancestral connectivity could be a recurrent feature of lineage divergence even in marine organisms with extremely restricted dispersal.

Rhodophyta↗

PubMed2026

SET domain bifurcated histone lysine methyltransferase 1 regulates histone modification and DNA damage response during zygotic genome activation in pigs.

SET domain bifurcated histone lysine methyltransferase 1 (SETDB1) is a key epigenetic regulator that catalyzes histone H3 lysine 9 trimethylation (H3K9me3), a mark essential for transcriptional repression and heterochromatin formation. Here, we investigated the role of SETDB1 during zygotic genome activation (ZGA) in porcine embryos. SETDB1 knockdown (KD) was induced by microinjecting double-stranded RNA (dsRNA), and its impact on early embryonic development was evaluated. SETDB1 KD decreased H3K9me3 levels, markedly increased H3K9ac, and downregulated ZGA-associated genes. These epigenetic alterations were accompanied by impaired cleavage, reduced blastocyst formation, and a lower total cell number. Upon etoposide-induced DNA double-strand breaks, SETDB1 KD embryos showed reduced expression of key DNA repair proteins, failed to efficiently restore DNA integrity, and exhibited increased apoptosis, indicating a compromised DNA damage response and repair process. SETDB1 KD also reduced HDAC3 expression, suggesting that SETDB1 may regulate HDAC3 to maintain histone acetylation balance. Consistently, HDAC3 inhibition increased H3K9ac, decreased H3K9me3, and reduced SETDB1 protein levels, supporting a reciprocal regulatory relationship. Together, these findings indicate that SETDB1 is important for porcine embryonic development by coordinating histone modifications and safeguarding genomic integrity during ZGA, and they suggest that the interplay between SETDB1 and HDAC3 constitutes a potentially important epigenetic axis for proper histone modification dynamics and developmental competence.

Animals↗

PubMed2026

Introgression shapes the genomic conflict landscape of Malus, providing evidence for a reticulate backbone in a woody crop lineage.

Phylogenomic discordance is widespread across plants, but its evolutionary significance is often obscured when conflict is treated primarily as analytical noise rather than as evidence of underlying processes. In woody lineages in particular, incomplete lineage sorting, introgression, and genome duplication can interact over long timescales to produce complex genomic histories that are not adequately summarized by a strictly bifurcating tree. Here, we use Malus as a model woody genus to investigate how these processes structure conflict across a genus-scale, accession-based phylogenomic framework. Using broad taxon sampling, hundreds of nuclear loci, plastid genomes, and genome-wide SNP summaries, we reconstruct a robust nuclear backbone for sampled Malus lineages and evaluate where discordance is concentrated and which processes best explain it. Nuclear analyses resolve eight major clades, whereas conflict is non-random and localized to recurrent hotspots rather than evenly distributed across the tree. Cytonuclear discordance is similarly concentrated, especially around Clade H, represented by sampled accessions of M. tschonoskii, where localized plastid-nuclear disagreement is consistent with candidate plastid capture or organellar introgression. Multiple complementary analyses further indicate that the strongest conflict is not explained by ILS alone, but instead reflects lineage-structured introgression, while polyploid complexes represent additional localized sources of evolutionary complexity. Together, these results provide evidence for a reticulate genomic backbone in Malus and show how integrating nuclear, plastid, and genome-wide conflict analyses can help distinguish background discordance from process-specific signals in woody plant radiations. Several lineage-level reticulation hypotheses identified here should now be tested with broader population-level sampling and curated reference accessions.

Malus↗

PubMed2026

Accurate quantification of canine mitochondrial DNA copy number from canine blood and brain samples.

Acute brain injury is difficult to evaluate in veterinary medicine and tools to investigate the potential involvement of mitochondrial involvement are limited. The brain is highly enriched in mitochondria and contains thousands of copies of mitochondrial DNA (mtDNA) per cell, but robust methods for quantifying mitochondrial DNA copy number (mtDNA-CN) in canine tissues are lacking. We describe the development of a quantitative real-time PCR assay for absolute measurement of mtDNA-CN which was validated in canine blood and brain tissue. To minimize amplification of nuclear mitochondrial insertion sequences (NumtS) and repetitive regions, species-specific oligonucleotide primers were designed following in silico genomic filtering. The assay was applied to a small pilot cohort comprising blood samples from dogs with and without acute brain injury (n = 4-6 per group) and cerebral cortex samples (n = 1 per group) to assess feasibility and biological plausibility. In non-brain injury dogs, blood mtDNA-CN ranged from 98 to 288 copies per nuclear genome (mean 193 ± 72), while values in brain-injured cases ranged from 163 to 228 copies per genome (mean 200 ± 33). Cerebral cortex samples exhibited higher mtDNA-CN than blood, consistent with known tissue-specific mitochondrial enrichment. In a single brain-injured case with serial sampling, mtDNA-CN increased over five days. This study presents a validated assay and pilot data for mtDNA-CN quantification in canine samples. While not powered for biomarker evaluation, this method may enable future studies of mitochondrial dynamics in canine brain injury and metabolic disease.

Animals↗