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Biology subjects

Fu, Z.

Publications and source records attributed to Fu, Z..

At least 19 recordsLinked to original sources

From micro-architecture to networks: canonical neurobiological architecture of functional brain organization across the lifespan and in psychopathology

Understanding how macroscale functional network connectivity (FNC) across the lifespan and in psychopathology is spatially organized with respect to microscale neurobiological architecture remains a challenge. Here, we constructed a cross-omics mapping framework by linking resting-state fMRI data (5,349 individuals, 6-80 years) with 49 neurobiological markers (24 cell types, 19 neurotransmitters, 6 mitochondria). We show that FNC development and aging unfold along cellular and molecular gradients. Specifically, spatial correspondence between age-related FNC changes and neurobiological microprofile networks varied by life stage, peaking for cell types in adolescence, neurotransmitter systems in mid-young adulthood and mitochondrial phenotypes in early adulthood. Applying normative modeling to 5 psychiatric disorders (schizophrenia, bipolar disorder, major depressive disorder, autism, and attention-deficit/hyperactivity disorder), we identified disorder-specific and cross-disorder FNC phenotypes spatially associated with neurobiological architecture. Together, these findings provide a hypothesis-generating framework linking functional brain organization and dysfunction to canonical neurobiological architecture across the lifespan and psychiatric disorders.

neuroscience↗

Pediatric brain charts reveal ADHD biotypes with distinct developmental, molecular, and therapeutic profiles

Attention-deficit/hyperactivity disorder (ADHD) exhibits profound clinical heterogeneity; however, its underlying neurobiological substrates remain unclear. Here, leveraging large - scale structural magnetic resonance imaging data from 12,663 typically developing children and 1,699 children with ADHD across Chinese and United States cohorts, we construct population specific pediatric brain charts via hierarchical Bayesian normative modeling to quantify individual deviations in cortical morphology. Data-driven clustering identifies two robust, cross - ethnically replicable ADHD biotypes: an infra - normal biotype characterized by widespread cortical thinning and a supra - normal biotype marked by cortical thickening. Multivariate analyses reveal distinct brain-behavior architectures: cortical deviations correlate preferentially with symptom severity in the infra-normal biotype but with both symptom severity and cognitive performance in the supranormal biotype. Clinically, the infra-normal biotype demonstrates a superior response to methylphenidate over atomoxetine, whereas the supra-normal biotype responds comparably to both. Transcriptomic analyses identify biotype-specific molecular signatures converging with ADHD genome-wide association study (GWAS) risk loci but exhibiting distinct expression patterns in the brain. These findings classify ADHD heterogeneity into neurobiologically distinct, clinically informed biotypes, providing a mechanistic framework for precision psychiatry in pediatric ADHD.

neuroscience↗

NeuroMark dFNC: Transferable Dynamic-State Templates for Subject-Specific and Frequency-Resolved Chronnectomics

Dynamic functional network connectivity (dFNC) commonly identifies recurring connectivity states from resting-state fMRI, but states derived independently in each dataset lack guaranteed correspondence across studies and cannot be directly estimated in new participants. We introduce NeuroMark dFNC, which extends the NeuroMark principle of prior-guided network estimation to dynamic connectivity by using reproducible reference states as priors for estimating corresponding subject-specific states. Reference-state templates were derived from UK Biobank using windowed functional network connectivity and time-frequency moments (TFMs), with split-sample reproducibility evaluated for k-means, independent component analysis (ICA), and principal component analysis (PCA) template-generation approaches. Constrained ICA then used the templates to estimate subject-specific state patterns and continuous loadings in independent FBIRN schizophrenia and ADNI Alzheimer's disease cohorts. ICA loadings were calibrated by their contribution to reconstruction of the original feature matrix. Fractional occupancy and conditional mean dwell time were calculated from the state with the largest absolute calibrated loading at each observation. The predefined templates avoided the need for dataset-specific state discovery and post-hoc state matching. In both clinical cohorts, the analysis identified state-dependent, distributed edgewise differences and differences in selected temporal summaries. Nominal frequency-resolved findings varied across states and moment-frequency bins and were treated as exploratory. NeuroMark dFNC provides a common state space for cross-cohort comparison while retaining subject-specific connectivity patterns and continuous state expression.

neuroscience↗

Integrated anthocyanin profiling and transcriptome analysis identify candidate genes associated with petal color variation in Cyclamen persicum

Petal coloration is a key ornamental trait in Cyclamen persicum Mill. and is closely associated with anthocyanin composition and relative accumulation, yet the major anthocyanins and candidate molecular factors associated with color variation remain unclear. In this study, anthocyanin profiling and transcriptome analysis were integrated to investigate three Cyclamen materials with distinct petal colors, BXK, FXK, and SHXK. Anthocyanin profiling showed clear separation among the three materials, indicating that petal color divergence was associated with differences in anthocyanin composition and relative abundance. Petunidin-, peonidin-, delphinidin-, malvidin-, and cyanidin-related derivatives exhibited distinct accumulation patterns. Transcriptome analysis revealed marked transcriptional divergence, with phenylpropanoid and flavonoid biosynthesis repeatedly enriched across comparisons, whereas isoflavonoid and flavone and flavonol biosynthesis were enriched in selected comparisons. Mapping differentially expressed genes onto the anthocyanin biosynthetic pathway revealed branch-specific expression patterns of structural genes, including CHS, F3H/F3'H, F3'5'H, DFR, and ANS. Notably, Cluster-26256.0, annotated as a putative anthocyanidin synthase gene, showed a progressive increase in expression from BXK to FXK and SHXK, consistent with increasing petal pigmentation. Several DFR-related transcripts also showed relatively high expression in SHXK. Co-expression analysis linked key anthocyanins, structural genes, and transcription factors, while qRT-PCR generally confirmed RNA-seq trends. These results suggest that late anthocyanin biosynthesis, particularly ANS-related transcriptional variation, may contribute to dark red petal coloration. This study provides a metabolite-transcript framework for Cyclamen petal coloration and identifies ANS-related genes as priority candidates for future functional studies and flower-color breeding.

plant biology↗

Targeting MAT2A-S-adenosylmethionine (SAM) Axis Attenuates DNA Damage Response and Cancer Stemness to Increase Platinum Sensitivity in Ovarian Cancer

Abstract Metabolic and epigenetic reprogramming drives development of platinum resistance and disease recurrence in high-grade serous ovarian cancer (HGSC), a major clinical challenge in the field. S-adenosylmethionine (SAM) is the universal methyl group donor, synthesized by methionine adenosyltransferase 2A (MAT2A) from methionine. Prior studies have linked altered SAM-dependent DNA methylation to acquired platinum resistance in HGSC, connecting metabolism and epigenetic regulation. However, how MAT2A-driven SAM synthesis coordinates the metabolic-epigenetic remodeling axis to affect platinum sensitivity remains unclear. Here, we report that MAT2A-driven SAM synthesis is required for platinum-induced alterations in DNA methylation and the enrichment of ovarian cancer stem cells (OCSCs). We found that MAT2A upregulation correlated with poor progression-free survival in OC patients, and both pharmacological inhibition and genetic knockdown of MAT2A increased sensitivity to cisplatin. To investigate the underlying epigenetic mechanism, we profiled genome-wide changes in DNA methylation using OVCAR3 treated with cisplatin (15M, 16hr) and/or MAT2A siRNA (48hr), which showed that MAT2A knockdown reversed platinum-induced DNA methylation dynamics. Subsequent analysis revealed enrichment of pathways associated with platinum resistance, DNA repair, and stemness. Mechanistically, inhibiting MAT2A abrogated both the platinum-induced hypermethylation at promoter regions and the SAMTOR-mTOR-S6K-FANCD2 signaling axis, resulting in accumulated R-loops, attenuated DNA repair activation in response to platinum, and enhanced platinum-induced DNA damage and cell death. Using a functional DNA damage reporter assay, we directly showed that MAT2A knockdown reduced DNA repair through homologous recombination (HR) and non-homologous end joining (NHEJ) pathways. By detecting key DNA damage response kinases governing HR and NHEJ signaling, we further demonstrated that MAT2A inhibition abrogated DNA repair activation in response to platinum. Furthermore, single-sample Gene Set Enrichment Analysis of paired primary and recurrent tumors from HGSC patients revealed an association between MAT2A expression and increased OCSC features in recurrent tumors. In vitro, MAT2A inhibition prevented cisplatin-induced enrichment of OCSCs, reduced stemness markers, and inhibited spheroid-forming ability, all of which were rescued by SAM supplementation. Together, our study reveals a previously unrecognized mechanism linking metabolism to epigenetic regulation through platinum-induced remodeling and establishes the MAT2A-SAM axis as a promising therapeutic target to enhance platinum sensitivity by abrogating DNA damage response and OCSC enrichment and ultimately reduce OCSC-driven disease recurrence in HGSC.

cancer biology↗

Kainate receptors coordinate primitive hematopoiesis and hemogenic niche organization to promote hematopoietic stem cell development

The adult hematopoietic system is established during embryogenesis through the generation of hematopoietic stem and progenitor cells (HSPCs) within specialized transient niches, yet the signaling mechanisms that coordinate this process remain poorly understood. Here, we identify a developmental role for kainate receptors (KARs), glutamate-gated ion channels classically associated with excitatory neurotransmission, in coordinating primitive hematopoiesis and hemogenic niche formation in zebrafish. Loss of the KAR subunits encoded by grik1b or grik5 depletes primitive blood cells and disrupts hemogenic niche organization. These defects are accompanied by endothelial oxidative stress and impaired Notch signaling, which together reduce HSPC emergence and limit the clonal diversity of the adult hematopoietic stem cell pool. Shifting primitive hematopoietic output away from erythropoiesis and toward myelopoiesis restored macrophage niche colonization, endothelial Notch activity, and HSPC formation in KAR-deficient embryos. Moreover, hemogenic cell-specific Notch reactivation rescued HSPC production, demonstrating that KAR-dependent primitive hematopoiesis regulates this process through endothelial Notch signaling. Lastly, conserved KAR expression in endothelial and hematopoietic populations across zebrafish, mouse, and human suggests that these receptors may regulate blood development across multiple cellular components. Together, these findings reveal that glutamate receptor signaling extends beyond its well-established functions in neuronal transmission to coordinate the developmental processes that establish the blood system.

developmental biology↗

Bioprinted Human Primary Arteries Recapitulate Inflammatory Activation and Pharmacologic Rescue

Chronic inflammation drives persistent systemic cytokine signaling that contributes to vascular dysfunction and secondary vasculitis, yet mechanistic studies are limited by models that fail to capture the multicellular architecture and dynamics of human arteries. In contrast, perfusing intact vessels ex vivo has limited tractability because of material availability and difficulty of genetic or biochemical manipulation. We developed a modular, perfused artery-on-a-chip platform by tri-axially bioprinting primary human vascular cells to recapitulate the concentric organization of the intimal, medial, and adventitial layers. The engineered vessels are viable longer than 21 days, with functional endothelial barriers, contractile smooth muscle behavior, and actively remodeled extracellular matrices bearing hallmarks of native vascular tissue. Addition of tumor necrosis factor alpha (TNF) induces altered transcript levels of proinflammatory mediators and secretion of cytokines and matrix-remodeling enzymes without compromising vessel viability. Importantly, this secretory response is effectively attenuated by both a small-molecule JAK1 inhibitor (ABT-317) and anti-TNF antibody (Infliximab), demonstrating the models utility for therapeutic evaluation.

bioengineering↗

Comparing Nonlinear Trajectories Across Brain Networks: A Key to Understanding Complex Brain Dynamics

This study explores the nonlinear developmental trajectories of brain networks in neurotypically developing infants during their first six months. Using a longitudinal dataset of 137 resting-state functional MRI scans from 74 infants, we analyzed five spatial metrics across 13 intrinsic connectivity networks, including motor, visual, subcortical, and prefrontal networks. A cubic model was specifically employed to capture distinct linear and non-linear trends in the networks developmental patterns, allowing for the identification of significant differences in cubic, quadratic, and linear slope parameters across networks. This model choice was driven by the need to examine how specific non-linear components (e.g., inflection points and acceleration rates) uniquely characterize each networks trajectory, which a generalized approach might smooth out without pinpointing such network-specific features. Notably, the subcortical network exhibited a distinct cubic growth pattern, while secondary motor and visual networks showed pronounced quadratic variations, suggesting network-specific shifts in spatial organization and connectivity. These findings highlight the unique maturation timelines and interactions between functional systems, such as early sensory-motor coordination and later cognitive integration. The results underscore the importance of network-specific growth patterns, providing deeper insights into how infant brain networks evolve and interact to support emerging cognitive and behavioral functions.

neuroscience↗

Ferroptosis is executed through caspase-5 cleavage of gasdermin E in ovarian cancer cells

Ferroptosis, an intracellular iron-catalyzed form of programmed cell death (PCD) driven by lipid reactive oxygen species induced membrane damage, is mechanistically uncharacterized in its execution process. Here, we investigated ferroptosis execution in mesenchymal-like ovarian cancer cells treated with ferroptosis inducers ML162 and erastin. We showed that YVAD (a pyroptosis-associated inflammatory caspase inhibitor) and disulfiram (preventing gasdermin pore formation on plasma membrane) deterred ferroptotic cell death. Moreover, we also observed LDH release and IL-1{beta} secretion from ferroptotic cells, suggesting that ferroptosis involves a pore-forming process. Intriguingly, ferroptosis is independent of the canonical inflammasome pathway because caspase-1 is dispensable and not activated upon ferroptosis induction. In contrast, we found that caspase-5 was activated while caspase-4 was not during ferroptosis. In addition, depletion of caspase-5 rendered cells not responding to ferroptosis inducers. Also intriguingly, GSDMD, the well-established caspase-5 substrate, was not involved in ferroptosis. We instead detected GSDME cleavage upon ferroptosis induction and knockdown of GSDME reduced cell death induced by ferroptosis inducers. As caspase-5 activity was necessary for ferroptosis and caspase-5 directly cleaved GSDME, we conclude that the axis of caspase-5/GSDME executes ferroptosis in ovarian cancer cells.

cell biology↗

Large-scale brain dynamics are organized by a directional coordination hierarchy

The cortical hierarchy is a central organizing feature of brain structure and function, yet whether it is continuously expressed in spontaneous neural activity remains unresolved. Here, we show that resting-state brain dynamics are organized along a directional coordination axis that recapitulates hierarchical information flow. Focusing on the directional dynamics of interregional coordination, we identify three recurrent coordination regimes: a feedback-dominated mode in which transmodal cortex leads sensory systems, a feedforward-dominated mode reflecting the reverse, and an integrative mode of balanced bidirectional exchange. These modes define a low-dimensional coordination landscape that replicates across four independent cohorts, establishing directional structure as a stable property of the adult brain. In schizophrenia, this landscape is selectively reorganized: feedback-dominated coordination becomes less persistent, integrative coordination becomes more persistent, and global dynamics shift toward faster convergence and reduced entropy, reflecting a loss of directional constraint and dynamical flexibility. These alterations track symptom severity, cognitive performance, and medication exposure. Mediation analyses suggest that medication-related reductions in integrative coordination are statistically routed through feedforward dynamics, consistent with dopaminergic modulation of recurrent cortical loops as a candidate mechanism. Together, these findings identify directional functional dynamics as a fundamental and clinically informative axis of large-scale brain organization.

neuroscience↗

Cortical vasodynamics exhibit multiscale propagation structure in the awake mouse

Spontaneous vasomotor rhythms and fluctuations are recognized contributors to functional MRI (fMRI) signals. Yet the spatial evolution of vasomotor contributions, which bear on the interpretation of fMRI signals in terms of functionally connected brain regions, remains unresolved. To clarify this issue, we analyze the 0.01 - 0.20 Hz space-frequency modes of 14T cerebral blood volume (CBV)-weighted fMRI across the awake mouse cortex. High-resolution CBV-fMRI identified single-vessel-aligned, frequency-specific modes of vasodynamic propagation, and ultra-fast CBV-fMRI enabled mapping of phase-gradients along tangential and radial axes. Tangential gradients extended maps of vasomotor traveling waves across the entire cortical mantle, with a median speed of 0.9 - 1.3 mm/s. Radial gradients revealed approximately three-fold slower changes in timing that support lamina-dependent regulation of perfusion. Region-specific differences in propagation speed and direction occur across cortical areas and between mice. These findings reframe vascular fluctuations as a feature of brain-wide physiology, as opposed to residual noise.

neuroscience↗

Microstimulation of the human dopaminergic midbrain causally reshapes value-based decision-making and happiness

Midbrain circuits are thought to govern reward-guided behavior and momentary happiness, yet causal evidence in humans remains scarce. Here, we show that focal microstimulation of the substantia nigra pars compacta alters both decision making and momentary happiness in patients undergoing awake deep-brain stimulation surgery for Parkinsons disease. During a gambling task with interleaved momentary happiness ratings, stimulation delivered at outcome reduced risk-seeking in the loss domain without increasing overall gambling probability. Stimulation improved choice efficiency, guiding behavior toward gambles with higher expected value and thereby increasing cumulative earnings. Computational modeling revealed selective changes in loss processing, with reduced loss weighting and more linear loss utility, while gain processing remained unchanged. In parallel, stimulation did not tonically elevate happiness but selectively amplified outcome-related happiness changes, scaling with decision value and reward prediction errors. These results provide causal evidence that localized perturbation of human midbrain circuits reshapes valuation, choice, and momentary well-being.

neuroscience↗

AAV-NRF2 protects retinal and choroidal vasculature in a GDF15-dependent manner in an oxidative damage model of AMD

Oxidative stress is proposed to be a driver of age-related diseases. Age-related macular degeneration is one such disease, where the retinal pigment epithelium (RPE) is affected early in the disease. Vasculature damage also occurs, sometimes preceding RPE damage. To model some aspects of dry AMD, we used the NaIO3 mouse model of oxidative damage. Disruption of the deep retinal vascular plexus, disorganization and death of capillaries within the choriocapillaris, and marked electroretinographic decline were observed. AAV overexpressing the transcription factor, NRF2, which induces anti-oxidation enzymes and represses inflammation, was tested for protection of damage. The BEST1 promoter limited expression to the RPE. The RPE, photoreceptors, and vascular architecture in both retinal and choroidal compartments were protected. Conditioned medium from RPE-choroid explants, infected by AAV8/BEST1-NRF2, was sufficient to transfer partial protection in vivo, indicating that NRF2 induces a protective secreted factor(s). Analysis of RNA-seq data identified growth differentiation factor 15 (GDF15) as a candidate downstream mediator. Injection of recombinant GDF15 reproduced key protective phenotypes in vivo, whereas Gdf15-deficiency attenuated NRF2-mediated rescue. Pharmacologic inhibition of TGF-{beta} receptor signaling diminished NRF2 associated protection, supporting involvement of this signaling pathway. In a laser-induced choroidal neovascularization model, intravitreal GDF15 injection reduced fluorescein leakage and lesion size. These findings support a model in which NRF2 activation in the RPE induces expression of GDF15, which is capable of protecting the RPE, photoreceptors, and the retinal and choroidal vasculature. NRF2 and GDF15 have therapeutic potential for ocular diseases, as well as for other diseases with vascular pathology.

cell biology↗

Hydrocephalus caused by Katnip deletion is linked to increased ciliogenesis and reduced proliferation of neuroprogenitor cells

BackgroundKATNIP (Katanin-interacting protein), also known as KIAA0556, is one of the human genes with pathogenic variants linked to Joubert syndrome, an archetypal neurodevelopmental ciliopathy. KATNIP is a scaffolding protein with a critical role in ciliogenesis. In this study, we characterized the ciliopathy phenotypes due to KATNIP gene deletion. ResultsWe produced a Katnip null mouse model using CRISPR-Cas12a (Cpf1). The null heterozygotes appeared normal while the homozygotes died around postnatal day 9, showing severe hydrocephalus and deficiency in neuroprogenitor cell proliferation. Katnip-deficient cells in the brain have a higher rate of cilia formation and longer cilia than wild type cells. ConclusionKATNIP loss of function gives rise to hydrocephalus found in Joubert syndrome. The results indicate that KATNIP restricts ciliogenesis and cilia extension and supports proliferation of neuroprogenitor cells in the brain.

cell biology↗

Autonomous error detection is enabled by conflict-dependent forward models in human medial frontal cortex

Learning from mistakes is fundamental for survival. Humans can monitor their behavior to detect action errors without external feedback, utilizing error information for adaptation and learning. How such errors are detected remains unknown. We investigated single neurons recorded from human medial frontal cortex while subjects performed a task in which conflict between target and distractor increases control demands and error likelihood. Population activity in presupplementary motor area (preSMA), but not dorsal anterior cingulate, encoded target and distractor responses distinctly and only in conflict trials. These representations were insensitive to response accuracy, indicating they reflect forward predictive models. Geometric alignment between target and actual response representations covaried with error commission, supporting the mismatch theory of error monitoring. Artificial neural networks trained to detect errors developed similar neural geometries. These findings identify a mechanism for detecting errors without external feedback and show that all signals required for this computation are present in preSMA.

neuroscience↗

Blood Based Biomarkers of DNA Methylation Associated with Platinum Resistance in High Grade Serous Ovarian Cancer

BackgroundHigh grade serous ovarian cancer (HGSC) is initially a responsive tumor to platinum (Pt)-based therapy. Pt resistance in HGSC is associated with epigenetic modifications and hypomethylating agents (HMAs) have been studied as carboplatin resensitizing agents. As DNA methylation is detectable in cancer cells and in blood, here we aimed to develop a blood-based methylation signature associated with cancer and cancer recurrence in HGSC. ResultsWe evaluated genome-wide DNA methylation in de-identified peripheral blood mononuclear cells (PBMCs) from women 1) without cancer (controls, n=20); 2) newly diagnosed HGSC (prior to treatment, Pt-naive, n=60) 3) Pt-resistant recurrent HGSC before and after treatment with the novel HMA/DNA methyltransferase inhibitor (DNMTI) guadecitabine (Pt-resistant, n=30). The Pt-resistant patients were enrolled in NCT02901899 clinical trial testing guadecitabine and the PD-1 inhibitor pembrolizumab. DNA extracted from PBMCs was analyzed by using Infinium MethylationEPIC BeadChips. There were 30,369 differentially methylated loci (DMLs) in Pt-naive patients vs. controls (adj. p < 0.05, {beta} >10%), with most loci being demethylated. Enriched pathways in PBMCs from cancer patients included mechanisms of cancer, neutrophil degranulation, and cancer-related signaling pathways (PI3K/AKT, STAT3, HGF, interleukins). The number of DMLs was greater (880 DMLs; adj. p<0.05, {beta}>10%) in Pt-resistant vs. Pt-naive patients, and top enriched pathways associated with Pt-resistant HGSC included pathways in cancer, metabolic pathways, platelet activation, ABC transporters and signaling pathways (calcium, PI3K/AKT, MAPK, Ras, ErbB, Hippo, Wnt). Massive genomewide hypomethylation 5 days after treatment with guadecitabine was observed (13,742 DMLs; adj. p<0.05, {beta}>10%), which persisted 30 days after discontinuation of treatment. Pathways enriched by hypomethylated genes in PBMCs following guadecitabine treatment interestingly included pathways related to neuronal signaling, such as glutaminergic receptor signaling, axonal guidance signaling, synaptic long-term depression, synaptogenesis signaling and serotonin receptor signaling. Deconvolution analysis of the methylome data of PBMCs from Pt-resistant recurrent HGSC before versus after HMA treatment predicted increased naive B cells, memory and naive CD+ T cells, naive CD4+ T cells, and neutrophils and decreased monocytes. ConclusionsWe propose new DMLs associated with Pt-naive versus Pt-resistant HGSC. These findings can lead to new biomarkers for HGSC.

genomics↗

Robustness of NeuroMark-Derived Functional Networks to fMRI Spatial Normalization Across the Human Lifespan

NeuroMark is a fully automated hybrid independent component analysis (ICA) framework designed to extract functional network features that are individually resolved and comparable across different cohorts. By integrating a reliable spatial template with spatially constrained ICA that adapts to each scan, NeuroMark retains the advantages of data-driven decomposition while avoiding limitations of fixed region-of-interest approaches. NeuroMark typically employs direct spatial normalization of fMRI data to a standardized adult EPI template; it remains unclear whether this approach is optimal for populations whose anatomy differs substantially from that of adults. We evaluated two normalization strategies in three large datasets spanning infancy, development, and aging: (1) direct normalization to the adult EPI template (EPInorm), and (2) normalization using an age-specific anatomical T1 template followed by transformation to the adult EPI template (T1toEPInorm). Across all cohorts, average intrinsic connectivity networks derived from EPInorm and T1toEPInorm exhibited very high spatial correspondence (mean {+/-} SD: 0.9966 {+/-} 0.0012 in infants; 0.9947 {+/-} 0.0019 in development; 0.9963 {+/-} 0.0012 in aging). The individual level also showed high similarity, though time courses showed slightly higher consistency than spatial maps (average correlations for time courses: 0.7990-0.9931; average correlations for spatial maps: 0.6879-0.9131). Functional network connectivity (FNC) measures were extremely well preserved across scans (95% of FNC with r > 0.9374 in infants; r > 0.8670 in developmental cohorts; r > 0.9219 in aging), demonstrating the robustness of NeuroMark features to different normalization strategies. Together, these results indicate that NeuroMark yields highly stable functional network features irrespective of whether an age-specific intermediate registration step is incorporated. NeuroMark, along with direct normalization to the adult EPI template, thus provides a robust, efficient, and harmonizable approach for large-scale, multisite, and lifespan neuroimaging studies, facilitating broad comparability across datasets while avoiding potential biases introduced by using multiple age-specific templates within a single study.

neuroscience↗

Structural Insights into the Integration of Temperature and pH by Sperm Calcium Channel CatSper

The cation channel of sperm (CatSper) is a sperm-specific calcium channel essential for male fertility across metazoans. Its activation is tightly restricted to defined physiological contexts, including intracellular alkalinization, membrane depolarization, and elevated temperature. The structural and evolutionary mechanisms underlying this polymodal integration remain poorly understood, in part due to the architectural complexity of CatSper, a [~]15-subunit assembly organized in zigzag arrays along the sperm flagellum. Here we combine comparative genomics across 47 species with AlphaFold3-based modeling and evolutionary sequence-structure analyses to uncover a mechanism for temperature and pH integration. We identify the pore-forming subunit CatSper1 as an evolutionary hotspot exhibiting exceptional divergence in its N-terminal domain. Phylogenetic analysis shows that N-terminal length and histidine enrichment scale with species-specific fertilization temperatures, suggesting adaptive tuning of physicochemical sensitivity. Structural modeling indicates that conserved surface-exposed histidine clusters form inter-complex coupling interfaces between adjacent CatSper assemblies positioned near the dominant voltage-sensing module. Functional validation using electrophysiology and calcium imaging in mouse sperm shows that capacitation-associated partial removal of the CatSper1 N-terminus selectively impairs temperature-dependent activation. Together, these findings support a model in which temperature-dependent histidine deprotonation modulates supramolecular CatSper assembly to coordinate channel activation.

physiology↗