Biology subjects

Chen, G.

Publications and source records attributed to Chen, G..

At least 145 records · Page 8Linked to original sources

bioRxiv2024

Two TAL effectors of Xanthomonas citri pv. malvacearum target GhSWEET15 as the susceptibility genes for bacterial blight of cotton

Bacterial Blight of Cotton (BBC) caused by Xanthomonas citri pv. malvacearum (Xcm) is an important and destructive disease affecting cotton plants. Transcription activator-like effectors (TALEs) released by the pathogen regulate cotton resistance to the susceptibility. In this study, we sequenced the whole genome of Xcm Xss-V2-18 and identified eight tal genes; seven on the plasmids and one on the chromosome. Deletion and complementation experiments of Xss-V2-18 tal genes demonstrated that Tal1b is required for full virulence on cotton. Transcriptome profiling coupled with TALE-binding element prediction revealed that Tal1b targets GhSWEET15A04/D04 and GhSWEET15D02 simultaneously. Expression analysis confirmed the independent inducibility of GhSWEET15A04/D04 and GhSWEET15D02 by Tal1b, whereas GhSWEET15A04/D04 is additionally targeted by Tal1. Moreover, GUS ({beta}-glucuronidase) and Xa10-mediated HR (hypersensitive response) assays indicated that the EBEs are required for the direct and specific activation of the candidate targets by Tal1 and Ta1b. These findings may advance our understanding of the dynamics between TALEs and EBEs, and decipher a simple and effective DNA-binding mechanism that could lead to the development of more efficient methods for gene editing and transgenic research.

pathology↗

bioRxiv2024

Size evolution of gigantic genomes suggests stochastic outcomes of transposable element/host silencing interactions

Size evolution among gigantic genomes involves gain and loss of many gigabases of transposable elements (TEs), sequences that parasitize host genomes. Animals suppress TEs using piRNA and KRAB-ZFP pathways. TEs and hosts coevolve in an arms race, where suppression strength reflects TE fitness costs. In enormous genomes, additional TE costs become miniscule. How, then, do TEs and host suppression invoke further addition of massive DNA amounts? We analyzed TE proliferation histories, deletion rates, and community diversities in six salamander genomes (21.3 - 49.9 Gb), alongside gonadal expression of TEs and suppression pathways. TE activity is higher in testes than ovaries, attributable to lower KRAB-ZFP suppression. Unexpectedly, genome size/expansion is uncorrelated with TE deletion rate, proliferation history, expression, and host suppression. Also, TE community diversity increases with genome size, contrasting theoretical predictions. TE/host antagonism in gigantic genomes likely produces stochastic TE accumulation, determined by noisy intermolecular interactions in huge genomes/cells.

evolutionary biology↗

bioRxiv2024

VirID: Beyond Virus Discovery - An Integrated Platform for Comprehensive RNA Virus Characterization

RNA viruses exhibit vast phylogenetic diversity and can significantly impact public health and agriculture. However, current bioinformatics tools for viral discovery from metagenomic data frequently generate false positive virus results, overestimate viral diversity, and misclassify virus sequences. Additionally, current tools often fail to determine virus-host associations, which hampers investigation of the potential threat posed by a newly detected virus. To address these issues we developed VirID, a software tool specifically designed for the discovery and characterization of RNA viruses from metagenomic data. The basis of VirID is a comprehensive RNA-dependent RNA polymerase (RdRP) database to enhance a workflow that includes RNA virus discovery, phylogenetic analysis, and phylogeny-based virus characterization. Benchmark tests on a simulated data set demonstrated that VirID had high accuracy in profiling viruses and estimating viral richness. In evaluations with real-world samples, VirID was able to identity RNA viruses of all type, but also provided accurate estimations of viral genetic diversity and virus classification, as well as comprehensive insights into virus associations with humans, animals, and plants. VirID therefore offers a robust tool for virus discovery and serves as a valuable resource in basic virological studies, pathogen surveillance, and early warning systems for infectious disease outbreaks.

bioinformatics↗

bioRxiv2024

Mutation of phosphatidate phosphohydrolase genes confers broad-spectrum disease resistance in plants

Phosphatidic acid (PA) is considered as a second messenger that interacts with protein kinases, phosphatases and NADPH oxidases, amplifying the signal to initiate plant defense signaling responses (Li and Wang, 2019). In rice, mutation of RBL1 causes the accumulation of PA, enhancing multipathogen resistance (Sha et al., 2023). In our previous study, we attempted to rescue rbl1 mutant by overexpressing phosphatidate phosphohydrolase (PAH) genes. However, overexpression of PAH2 reduced the PA level but did not affect the disease resistance, which made us to reconsider the importance of PA and PAH in rice immunity. Here, we identified that mutation of PAHs caused PA accumulation and enhanced multipathogen resistance in rice and Arabidopsis.

plant biology↗

bioRxiv2024

A Drug-Elicitable Alternative-Splicing Module (DreAM) for Tunable AAV Expression and Controlled Myocardial Regeneration

Adeno-associated virus (AAV) is a major vector for gene therapy. A technique to fine-tune the time and level of AAV expression is lacking, which greatly restricts indication choice, therapeutic efficacy and safety. To solve this problem, here we developed a drug-elicitable alternative-splicing module (DreAM) responsive to risdiplam, an FDA-approved alternative splicing modulator. Risdiplam activates DreAM-regulated AAV expression in a dose-dependent manner with an over 2000-fold inducible change depending on the inducer dosage and the organ of interests. With a temporally resolution of a couple of days, DreAM could repeatedly activate AAV expression, determined by the frequency and duration of risdiplam administration. As an example of DreAM-realized gene therapy, this technique was used to control AAV-based cardiac delivery of YAP5SA, a potent cardiomyocyte regeneration factor. DreAM transiently activated AAV-YAP5SA, establishing the dedifferentiation-proliferation-redifferentiation cycle in cardiomyocytes. Consequently, DreAM fulfilled the regenerative capacity of AAV-YAP5SA in myocardial infarction while circumventing toxicity associated with prolonged AAV-YAP5SA expression. Together, these data demonstrated a tremendous potential of DreAM to enhance the efficacy, safety and applicable scope of gene therapy.

bioengineering↗

bioRxiv2024

Neural Heterogeneity Enhances Reliable Neural information Processing: Local Sensitivity and Globally Input-slaved Transient Dynamics

Cortical neuronal activity varies over time and across repeated stimulation trials, yet consistently represents stimulus features. The dynamical mechanism underlying this reliable representation and computation remains elusive. This study uncovers a mechanism that achieves reliable neural information processing, leveraging a biologically plausible network model with neural heterogeneity. We first investigate neuronal timescale diversity in reliable computation, revealing it disrupts intrinsic coherent spatiotemporal patterns, enhances local sensitivity, and aligns neural network activity closely with inputs. This leads to local sensitivity and globally input-slaved transient dynamics, essential for reliable neural processing. Other neural heterogeneities, such as non-uniform input connections and spike threshold heterogeneity, plays similar roles, highlighting neural heterogeneitys role in shaping consistent stimulus representation. This mechanism offers a potentially general framework for understanding neural heterogeneity in reliable computation and informs the design of new reservoir computing models endowed with liquid wave reservoirs for neuromorphic computing. TeaserNeural diversity disrupts spatiotemporal patterns, aligning network activity with inputs for reliable information processing.

neuroscience↗

bioRxiv2024

Inhibitor of cardiolipin biosynthesis-related enzyme MoGep4 confers broad-spectrum anti-fungal activity

Plant pathogens cause devastating diseases, leading to serious losses to agriculture. Mechanistic understanding of pathogenesis of plant pathogens lays the foundation for the development of fungicides for disease control. Mitophagy, a specific form of autophagy, is important for fungal virulence. The role of cardiolipin, mitochondrial signature phospholipid, in mitophagy and pathogenesis is largely unknown in plant pathogenic fungi. The functions of enzymes involved in cardiolipin biosynthesis and relevant inhibitors were assessed using a set of assays, including genetic deletion, plant infection, lipidomics, chemical-protein interaction, chemical inhibition, and field trials. Our results showed that the cardiolipin biosynthesis-related gene MoGEP4 of the rice blast fungus Magnaporthe oryzae regulates growth, conidiation, cardiolipin biosynthesis, and virulence. Mechanistically, MoGep4 regulated mitophagy and Mps1-MAPK phosphorylation, which are required for virulence. Chemical alexidine dihydrochloride (AXD) inhibited the enzyme activity of MoGep4, cardiolipin biosynthesis and mitophagy. Importantly, AXD efficiently inhibited the growth of 10 plant pathogens and controlled rice blast and Fusarium head blight in the field. Our study demonstrated that MoGep4 regulates mitophagy, Mps1 phosphorylation and pathogenesis in M. oryzae. In addition, we found that the MoGep4 inhibitor, AXD, displays broad-spectrum antifungal activity and is a promising candidate for fungicide development.

microbiology↗

bioRxiv2024

Calorie Restriction Induces Degeneration of Neurons with Mitochondrial DNA Depletion by Altering ER-Mitochondria Calcium Transfer

Mitochondrial DNA (mtDNA) mutations and/or depletion are implicated in epilepsy and many neurodegenerative diseases. However, systematic investigation into how mtDNA alterations relate to epilepsy and neural degeneration is needed. Here, we established a mouse model where in mtDNA depletion induced by Herpes Simplex Virus Type 1 (HSV-1) protein-UL12.5 in the brain led to an epileptic phenotype characterized by abnormal electroencephalography (EEG) patterns and increased neural excitability in hippocampus. We also found that UL12.5 mediated mtDNA depletion in neurons in vitro (rho-) causes epilepsy-like abnormal EEG. Caloric restriction (CR) is a strategy proven to reduce epileptic activity, however CR mimetic 2-deoxy-D-glucose (2-DG), induced degeneration in mtDNA depleted neurons. Mechanistically, mtDNA depletion increased mitochondria-endoplasmic reticulum (ER) contacts, facilitating CR-induced mitochondrial calcium overload. Rho- neurons did not show changes in mitochondrial motility or membrane potential. Our study revealed an unexpected axis of mtDNA depletion, ER-mitochondrial contacts, and calcium overload in the rho- neuron model. This is the first description of animal and neuronal models of mitochondrial epilepsy. Our findings with these models suggest that CR may not be a viable clinical intervention in patients with mtDNA depletion.

cell biology↗

bioRxiv2024

Myocardial infarction creates a critical time window for AAV gene therapy

Recombinant adeno-associated virus (AAV) is a major gene delivery vector for cardiac gene therapy. The factors that influence AAV-based cardiac gene transfer remain incompletely understood. This study showed that myocardial infarction (MI) enhanced cardiac AAV transduction and gene expression in mice after systemic administration, peaking at the third day post MI. These additional AAV vectors enriched at the infarcted region, correlated with the pathological permeabilization of the coronary vessels. The outcome of AAV-base gene therapy for MI, via Camk2d base editing, was significantly improved when AAV was injected at the third day post MI. Together, our findings uncovered a critical therapeutic time window after MI that facilitated AAV-based cardiac gene transfer, which could be harnessed to boost both basic and translational cardiology. MethodsAdult C57BL/6 mice were subjected to left anterior descending (LAD) coronary artery ligation. Permanent LAD ligation created the MI model while 30min ligation followed by reperfusion established the ischemia/reperfusion (I/R) model. 2x1011 AAV vectors were injected into the mice via tail vein. The AAV vectors carried transgenes that were activated by the cardiomyocyte-specific Tnnt2 promoter or the constitutively active CMV promoter. AAV expressed luciferase with the hemagglutinin (HA) tag. The amount of AAV vectors were quantified by real-time quantitative PCR (RT-qPCR) analysis of genomic DNA. Transgene expression was measured by RT-qPCR at the mRNA level or HA tag immunofluorescence imaging and western blot at the protein level. Luciferase activity was measured via bioluminescence imaging.

physiology↗

bioRxiv2024

Structural characterization and AlphaFold modeling of human T cell receptor recognition of NRAS cancer neoantigens

T cell receptors (TCRs) that recognize cancer neoantigens are important for anti-cancer immune responses and immunotherapy. Understanding the structural basis of TCR recognition of neoantigens provides insights into their exquisite specificity and can enable design of optimized TCRs. We determined crystal structures of a human TCR in complex with NRAS Q61K and Q61R neoantigen peptides and HLA-A1 MHC, revealing the molecular underpinnings for dual recognition and specificity versus wild-type NRAS peptide. We then used multiple versions of AlphaFold to model the corresponding complex structures, given the challenge of immune recognition for such methods. Interestingly, one implementation of AlphaFold2 (TCRmodel2) was able to generate accurate models of the complexes, while AlphaFold3 also showed strong performance, although success was lower for other complexes. This study provides insights into TCR recognition of a shared cancer neoantigen, as well as the utility and practical considerations for using AlphaFold to model TCR-peptide-MHC complexes.

immunology↗

bioRxiv2024

Production of four-gene (GTKO/hCD55/hTBM/hCD39)-edited donor pigs and kidney xenotransplantation

BackgroundThe number of multigene-modified donor pigs for xenotransplantation is increasing with the advent of gene editing technologies. However, which gene combination is suitable for which organ transplantation remains unclear. MethodsIn this study, we utilized CRISPR/Cas9 gene editing technology, PiggyBac transposon system and somatic cell cloning to construct GTKO/hCD55/hTBM/hCD39 four-gene-edited cloned (GEC) pigs and performed kidney transplantation from pig to rhesus monkey to evaluate the effectiveness of these GEC pigs. ResultsFirst, 107 cell colonies were obtained through drug selection, of which 7 were 4-GE colonies. Two colonies were selected for somatic cell nuclear transfer, resulting in 7 fetuses, of which 4 were GGTA1 biallelic knockout. Both fetuses had higher expression of hCD55, hTBM and hCD39. Therefore, these two fetuses were selected for two consecutive rounds of cloning, resulting in a total of 97 live piglets. After phenotype identification, the GGTA1 gene of these pigs was inactivated, and hCD55, hTBM and hCD39 were expressed in cells and multiple tissues. Furthermore, the numbers of monkey IgM and IgG binding to the peripheral blood mononuclear cells (PBMCs) of the 4-GEC pigs were markedly reduced. Moreover, 4-GEC porcine PBMCs had greater survival rates than those from wild-type pigs through complement-mediated cytolysis assays. In pig-to-monkey kidney xenotransplantation, the kidney xenograft successfully survived for 11 days. All physiological and biochemical indicators were normal, and no hyperacute rejection or coagulation abnormalities were found after transplantation. ConclusionThese results indicate that the GTKO/hCD55/hTBM/hCD39 four-gene modification effectively alleviates immune rejection, and the pig kidney can functionally support the recipient monkeys life.

genetics↗

bioRxiv2024

Cardioprotection by Poloxamer 188 is Mediated through Increased Endothelial Nitric Oxide Production

Ischemia/reperfusion (I/R) injury significantly contributes to the morbidity and mortality associated with cardiac events. Poloxamer 188 (P188), a nonionic triblock copolymer, has been proposed to mitigate I/R injury by stabilizing cell membranes. However, the underlying mechanisms remain incompletely understood, particularly concerning endothelial cell function and nitric oxide (NO) production. We employed human induced pluripotent stem cell (iPSC)-derived cardiomyocytes (CMs) and endothelial cells (ECs) to elucidate the effects of P188 on cellular survival, function, and NO secretion under simulated I/R conditions. iPSC-CMs contractility and iPSC-ECs NO production were assessed following exposure to P188. Further, an isolated heart model using Brown Norway rats subjected to I/R injury was utilized to evaluate the ex-vivo cardioprotective effects of P188, examining cardiac function and NO production, with and without the administration of a NO inhibitor. In iPSC-derived models, P188 significantly preserved CM contractile function and enhanced cell viability after hypoxia/reoxygenation. Remarkably, P188 treatment led to a pronounced increase in NO secretion in iPSC-ECs, a novel finding demonstrating endothelial protective effects beyond membrane stabilization. In the rat isolated heart model, administration of P188 during reperfusion notably improved cardiac function and reduced I/R injury markers. This cardioprotective effect was abrogated by NO inhibition, underscoring the pivotal role of NO. Additionally, a dose-dependent increase in NO production was observed in non-ischemic rat hearts treated with P188, further establishing the critical function of NO in P188 induced cardioprotection. In conclusion, our comprehensive study unveils a novel role of NO in mediating the protective effects of P188 against I/R injury. This mechanism is evident in both cellular models and intact rat hearts, highlighting the potential of P188 as a therapeutic agent against I/R injury. Our findings pave the way for further investigation into P188s therapeutic mechanisms and its potential application in clinical settings to mitigate I/R-related cardiac dysfunction.

pharmacology and toxicology↗

bioRxiv2024

Production and functional verification of 8-gene (GGTA1, CMAH, β4GalNT2, hCD46, hCD55, hCD59, hTBM, hCD39)-edited donor pigs for xenotransplantation

Gene-edited pig-to-human xenotransplantation continues to make breakthroughs and is expected to enter clinic to solve the global shortage of donor organs. However, which gene combination is suitable for which organ transplantation remains unclear. In this study, we utilized CRISPR/Cas9 gene editing technology, PiggyBac transposon system and somatic cell cloning to construct GTKO/CMAHKO/{beta}4GalNT2KO/hCD46/hCD55/hCD59/hCD39/hTBM 8 gene-edited cloned (GEC) donor pigs, and performed pig to non-human primate (NHP) transplantation to evaluate the effectiveness of these GEC pigs. The multiple vectors were co-transfected into fetal fibroblasts of Diannan miniature pig with O blood type, and 25 colonies were screened out, and one of them carried GGTA1, CMAH and {beta}4GalNT2 biallelic knockout and integration of hCD46, hCD55, hCD59, hTBM and hCD39 genes, which was used as a donor cell for cloning, and a 33-day-old viable fetus was obtained. The fetus was identified and confirmed for normal karyotype and the absence of three xenogeneic antigens -Gal, Neu5Gc and Sda, and expression of hCD46, hCD55, hCD59, hTBM and hCD39 genes, then the recloning was carried out and 28 cloned piglets were obtained by natural delivery. Molecular identification at DNA, mRNA and protein levels showed that 8 gene editing (GE) was successful in these GEC piglets. Moreover, antigen-antibody binding assay and complement-dependent cytotoxicity assay demonstrated that 8GE effectively reduced the immune incompatibility and kidney xenograft survived up to 15 and 17 days into two NHPs, respectively. During this period, the recipient serum antibodies IgA and IgM, complements C3 and C4, coagulation indicators PT, APTT, TT and FIB, as well as most electrolytes and liver function indicators remained relatively stable. The 24-hour urine output and serum creatinine remained normal at a period of post-transplantation. These results indicated that the 8GEC pigs effectively alleviated immune rejection and exerted life-supporting kidney function in the recipient.

genetics↗

bioRxiv2024

Recognition of RNA secondary structures with a programmable peptide nucleic acid-based platform

RNA secondary structures comprise double-stranded (ds) and single-stranded (ss) regions. Antisense peptide nucleic acids (asPNAs) enable the targeting of ssRNAs and weakly formed dsRNAs. Nucleobase-modified dsRNA-binding PNAs (dbPNAs) allow for targeting of relatively stable dsRNAs. A programmable RNA structure-specific targeting strategy is needed for simultaneous recognition of dsRNAs and ssRNAs. Here, we report on combining dbPNAs and asPNAs (designated as daPNAs) for the targeting of dsRNA-ssRNA junctions. Our binding and modeling data suggest that combining traditional asPNA (with a 4-letter code: T, C, A, and G) and dbPNA (with a 4-letter code: T or s2U, L, Q, and E) scaffolds facilitates RNA structure-specific tight binding (nM to M) under physiologically-relevant conditions. We further applied our daPNAs in substrate specific inhibition of Dicer acting on pre-miR-198 in a cell-free assay and regulating ribosomal frameshifting induced by model hairpins in both cell-free and cell culture assays. daPNAs would be a useful platform for developing chemical probes and therapeutic ligands targeting RNA. HighlightO_LIWe demonstrated that sequence- and structure-specific targeting of RNA can be facilitated by nucleobase-modified dsRNA-binding PNAs (dbPNAs) platform in combination with antisense PNAs (asPNAs). We name the novel PNAs as daPNAs. C_LIO_LIdaPNAs can be used in a programmable way for targeting RNAs by formation of a short triplex next to a short duplex at a dsRNA-ssRNA junction. C_LIO_LIWe applied our daPNAs in substrate specific inhibition of Dicer acting on pre-miR-198 in a cell-free assay and regulating ribosomal frameshifting induced by model hairpins in both cell-free and cell culture assays. C_LIO_LIThe daPNAs platform would serve as useful junction-specific molecular glues for the targeting of many biologically important RNA structures in transcriptomes. C_LI

biochemistry↗

bioRxiv2024

Enhanced Recognition of a Herbal Compound Epiberberine by a DNA Quadruplex-Duplex Structure

The small molecule epiberberine (EPI) is a natural alkaloid with versatile bioactivities against several diseases, including cancer and bacterial infection. EPI can induce the formation of a unique binding pocket at the 5' side of a human telomeric G-quadruplex (HTG) sequence Q4, resulting in a nanomolar binding affinity (KD approximately 26 nM) with significant fluorescence enhancement upon binding. It is important to understand (1) how EPI binding affects HTG structural stability and (2) how enhanced EPI binding may be achieved through the engineering of the DNA binding pocket. In this work, the EPI binding-induced HTG structure stabilization effect was probed by a peptide nucleic acid (PNA) invasion assay in combination with a series of biophysical techniques. We show that the PNA invasion-based method may be useful for the characterization of compounds binding to DNA (and RNA) structures in physiological conditions without the need to vary the solution temperature or buffer components, which are typically needed for structural stability characterization. Importantly, the combination of theoretical modeling and experimental quantification allows us to successfully engineer the Q4 derivative Q4-ds-A by a simple extension of a duplex structure to Q4 at the 5' end. Q4-ds-A is a superb EPI binder with a KD of 8 nM, with the binding enhancement achieved through the preformation of a binding pocket and a reduced dissociation rate. The tight binding of Q4 and Q4-ds-A with EPI allows us to develop a novel magnetic bead-based affinity purification system to effectively extract EPI from Rhizoma coptidis (Huang Lian) extracts.

biochemistry↗

bioRxiv2024

Individual variability in the relationship between physiological and resting-state fMRI metrics

Cerebrovascular Reactivity (CVR), the brains vascular response to a vasodilatory stimulus, can be measured using fMRI during breathing challenges that modulate arterial CO2 levels. CVR is an important indicator of cerebrovascular health, although its estimation can be challenging due to the extra experimental setup and/or the subject compliance required. To overcome these limitations, summary metrics based on resting state fluctuations (RSF), such as the (fractional) amplitude of low frequency fluctuations (f/ALFF) and the resting state fluctuation amplitude (RSFA), have been proposed as alternative estimates of CVR, as they are frequently associated with vascular and physiological factors. Previous studies have reported a significant relationship between CVR estimates obtained by means of respiratory paradigms and RSF metrics. However, the total sample sizes, considering both subjects and sessions, are typically small, and not all studies agree on the degree of the relationship. Furthermore, to our knowledge, these studies have only reported cross-sectional analyses, whereas intra-subject longitudinal relationships between CVR estimates and RSF metrics are unknown. Leveraging a unique dense sampling dataset in which resting state and breath-hold multi-echo fMRI were collected in 7 subjects with 10 sessions each, we provide evidence of high individual variability in the inter-session (i.e. intra-subject) relationship between RSF metrics and CVR. These results indicate that RSF metrics might not be a suitable proxy of CVR in clinical settings or for BOLD signal calibration as they may not properly account for intra-individual physiological variations in BOLD fMRI data.

neuroscience↗

bioRxiv2024

siRNADesign: A Graph Neural Network for siRNA Efficacy Prediction via Deep RNA Sequence Analysis

The clinical adoption of small interfering RNAs (siRNAs) has prompted the development of various computational strategies for siRNA design, from traditional data analysis to advanced machine learning techniques. However, previous studies have inadequately considered the full complexity of the siRNA silencing mechanism, neglecting critical elements such as siRNA positioning on mRNA, RNA base-pairing probabilities, and RNA-AGO2 interactions, thereby limiting the insight and accuracy of existing models. Here, we introduce siRNADesign, a Graph Neural Network (GNN) framework that leverages both non-empirical and empirical rules-based features of siRNA and mRNA to effectively capture the complex dynamics of gene silencing. In multiple internal datasets, siRNADesign achieves state-of-the-art performance. Significantly, siRNADesign also outperforms existing methodologies in in vitro wet lab experiments and an externally validated dataset. Additionally, we develop a new data-splitting methodology that addresses the data leakage issue, a frequently overlooked issue in previous studies, ensuring the robustness and stability of our model under various experimental settings. Through rigorous testing, siRNADesign has demonstrated remarkable predictive accuracy and robustness, making significant contributions to the field of gene silencing. Furthermore, our approach in redefining data-splitting standards aims to set new benchmarks for future research in the domain of predictive biological modeling for siRNA.

bioinformatics↗

bioRxiv2024

Complementary benefits of multivariate and hierarchical models for identifying individual differences in cognitive control

Understanding individual differences in cognitive control is a central goal in psychology and neuroscience. Reliably measuring these differences, however, has proven extremely challenging, at least when using standard measures in cognitive neuroscience such as response times or task-based fMRI activity. While prior work has pinpointed the source of the issue -- the vast amount of cross-trial variability within these measures -- solutions remain elusive. Here, we propose one potential way forward: an analytic framework that combines hierarchical Bayesian modeling with multivariate decoding of trial-level fMRI data. Using this framework and longitudinal data from the Dual Mechanisms of Cognitive Control project, we estimated individuals neural responses associated with cognitive control within a color-word Stroop task, then assessed the reliability of these individuals responses across a time interval of several months. We show that in many prefrontal and parietal brain regions, test-retest reliability was near maximal, and that only hierarchical models were able to reveal this state of affairs. Further, when compared to traditional univariate contrasts, multivariate decoding enabled individual-level correlations to be estimated with significantly greater precision. We specifically link these improvements in precision to the optimized suppression of cross-trial variability in decoding. Together, these findings not only indicate that cognitive control-related neural responses individuate people in a highly stable manner across time, but also suggest that integrating hierarchical and multivariate models provides a powerful approach for investigating individual differences in cognitive control, one that can effectively address the issue of high-variability measures.

neuroscience↗