Biology subjects

Zhong, J.

Publications and source records attributed to Zhong, J..

At least 55 records · Page 3Linked to original sources

bioRxiv2025

RAD51AP1 is a versatile RAD51 modulator

RAD51AP1 is an emergent key factor in homologous recombination (HR), the major pathway for accurate repair of DNA double-strand breaks, and in alternative lengthening of telomeres (ALT). Depletion of RAD51AP1 diminishes HR and overexpression is common in cancer, where it is associated with malignancy. Here, we show that RAD51AP1 serves as a versatile modulator of the RAD51 recombinase, the central player in HR. Through a combination of biochemistry and structural biology, we reveal that RAD51AP1 possesses at least three RAD51-binding sites that facilitate its binding across two adjacent RAD51 molecules. We uncover a novel RAD51 binding mode and characterise a hitherto overlooked role for RAD51AP1 in stabilising RAD51-ssDNA filaments and promoting strand exchange. Further, we resolved structures of RAD51-ssDNA filaments in the presence of Mg2+-ATP and Mg2+-ADP, revealing conformational changes upon ATP hydrolysis and explaining how ADP reduces RAD51-DNA binding. Our findings provide mechanistic insights into RAD51 recombinase and RAD51AP1. HighlightsO_LIStructures of RAD51 filaments in the presence of Mg2+-ATP and Mg2+-ADP reveal how ATP hydrolysis reduces DNA binding C_LIO_LIATP hydrolysis does not induce RAD51 filament contraction, instead it induces filament relaxation C_LIO_LIRAD51AP1 uses three sites to bind across two RAD51 monomers C_LIO_LIRAD51AP1 uses a unique binding mode to stabilise the RAD51 N-terminal domain and protomer interface of RAD51 C_LIO_LIRAD51AP1 binding induces conformational changes that promote RAD51 DNA association, oligomerisation, filament nucleation, filament stabilisation and strand exchange C_LI

biochemistry↗

bioRxiv2025

Senescence-induced reparative fibroblasts enable scarless wound healing in aged murine skin.

It has been reported that elderly individuals exhibit reduced scarring during the wound healing process compared to younger adults. However, the underlying mechanisms responsible for this phenomenon remain poorly understood. Here, we revealed that aged mice exhibited more pronounced regenerative outcomes compared to young mice, characterized by increased hair follicle numbers and collagen fiber features closer to normal skin. Single-cell sequencing identified a reparative fibroblast subpopulation (Prss35+Fib) enriched in the aged group, which promotes regeneration through communication with epithelial cells, macrophages, and T cell subpopulations via PTN and EREG signaling. Spatial transcriptomics validated this communication pattern by elucidating cell proximity and locating the regenerative niche in the upper dermis. Finally, EREG treatment significantly enhanced regenerative outcomes in young mice, while the small wound model of aged mice, lacking the reparative fibroblast and EREG signaling, failed to achieve regeneration. Collectively, our findings advance the understanding of regenerative plasticity in aging and provide new insights for designing scarless therapeutic strategies.

cell biology↗

bioRxiv2025

Characterization of the Mechanisms Underlying Sulfasalazine-Induced Ferroptotic Cell Death: Role of Protein Disulfide Isomerase-Mediated NOS Activation and NO Accumulation

Sulfasalazine (SAS), a clinically-utilized anti-inflammatory drug, has been shown to induce ferroptosis by inhibiting system Xc- activity, thereby causing cellular glutathione depletion. Recently, it was shown that protein disulfide isomerase (PDI) is an upstream mediator of oxidative cell death (oxytosis/ferroptosis) induced by glutamate, erastin, RSL3 and SAS. The present study aims to further characterize the detailed biochemical and cellular mechanisms of SAS-induced ferroptosis in two cell lines, i.e., H9C2 rat cardiomyocytes and BRL-3A rat hepatocytes, focusing on elucidating the critical role of PDI in mediating SAS-induced toxicity. We find that SAS can induce ferroptosis in H9C2 and BRL-3A cells, which is accompanied by a sequential increase in the buildup of cellular nitric oxide (NO), reactive oxygen species (ROS) and lipid-ROS. SAS activates PDI-mediated dimerization of the inducible NO synthase (iNOS) and cellular NO accumulation, and these effects are followed by ROS and lipid-ROS accumulation. Furthermore, SAS markedly upregulates the expression of iNOS protein in these cells. Knockdown of PDI or pharmacological inhibition of its catalytic activity each effectively suppresses SAS-induced iNOS dimerization, along with abrogation of SAS-induced accumulation of NO, ROS and lipid-ROS, and prevention of ferroptosis. On the other hand, PDI activation through the use of TrxR1 inhibitors sensitizes these cells to SAS-induced ferroptosis. These experimental findings provide further experimental support for a pivotal role of PDI in SAS-induced cytotoxicity through the activation of the PDI-NOS-NO axis, which then leads to cellular ROS and lipid-ROS accumulation, and ultimately induction of oxidative cell death.

biochemistry↗

bioRxiv2025

Suite3D: Volumetric cell detection for two-photon microscopy

In two-photon imaging of neuronal activity it is increasingly common to acquire 3-dimensional volumes. However, these volumes are typically processed plane by plane, leading to uncorrected axial movement, duplicated cells across planes, reduced signal-to-noise ratio per cell, and missed cells. To overcome these limitations, we introduce Suite3D, a volumetric cell detection pipeline. Suite3D corrects for rigid and non-rigid 3D brain motion, both lateral and axial. It detects neurons using 3D correlation, improving detectability. Finally, it performs 3D segmentation, identifying cells across imaging planes. We validated Suite3D with data from conventional multi-plane microscopes and advanced volumetric microscopes, at multiple resolutions and in multiple brain regions, and with ground truth anatomical labelling. Suite3D successfully detected cells appearing on multiple imaging planes, improving cell detectability and signal quality, avoiding duplications, and running faster than a prior volumetric pipeline. Suite3D offers a powerful solution for analyzing volumetric two-photon data.

neuroscience↗

bioRxiv2025

FACED 2.0 enables large-scale voltage and calcium imaging in vivo

Monitoring neuronal activity at large scale and high spatiotemporal resolution is crucial for understanding information processing within the brain. We optimized a kilohertz-frame-rate two-photon fluorescence microscope with all-optical megahertz line-scan rate to achieve ultrafast imaging across large areas and volumes at subcellular resolution. Applying this technique to voltage and calcium imaging in vivo, we demonstrated simultaneous recording of voltage activity over 200 neurons and calcium activity over 14,000 neurons.

neuroscience↗

bioRxiv2025

An integrated system for comprehensive mouse peripheral vestibular function evaluation based on Vestibulo-ocular Reflex

In the realms of both vestibular and auditory research, conducting vestibular function tests is essential. However, unlike the auditory function tests which utilize standard equipment such as the Auditory Brainstem Response (ABR) device, there is no equivalent widely adopted apparatus for vestibular tests. This is largely due to the intricate nature of the vestibular system and the challenges associated with assessing its functions. Vestibulo-ocular reflexes (VORs) are the compensatory ocular reflexes that ensure stable vision during head motion. VORs are widely used in clinics for diagnosing the vestibular deficit. In the research field, VORs, including angular VOR (aVOR) or off-vertical axis rotation (OVAR) tests, have been used by various groups to evaluate the mouse vestibular function. However, the effectiveness of VOR tests has not been systematically evaluated with proper animal models, and the lack of commercial equipment hampers its accessibility, confining vestibular testing to a select few labs. In this study, we developed an integrated instrument system with both aVOR and OVAR modes for evaluating mouse vestibular function. To demonstrate its efficacy, peripheral vestibular animal models, 1) Vestibulotoxicity drugs 3,3-iminodiproprionitrile (IDPN, 2 mg/g and 4 mg/g) induced; 2) Critical MET-related mutant (Cdh23v2J/v2J and TMC1-/-); 3) Vestibulo-specific mutant (Zpld1-/- for semicircular canal dysfunction and Otop1tlt/tlt for otoconia deficient; 4) Unilateral vestibular lesion (UVL) model by injecting gentamicin into horizontal semicircular canal, were constructed and evaluated with the system. The results showed 1) Quantification of the vestibular deficit is achieved in a daily manner; 2) Both the otolith organ and semicircular canals can be assessed respectively; and 3) The lesion side of UVL can be identified. During an 8-week study of IDPN vestibulotoxicity, the vestibular function of 3 groups of 20 animals was evaluated at 15 test days. These test results reveal the potential of our system as a standard system for evaluating common vestibular deficits in mice.

neuroscience↗

bioRxiv2025

Benchmarking gene embeddings from sequence, expression, network, and text models for functional prediction tasks

Accurate, data-driven representations of genes are critical for interpreting high-throughput biological data, yet no consensus exists on the most effective embedding strategy for common functional prediction tasks. Here, we present a systematic comparison of 38 gene embedding methods derived from amino acid sequences, gene expression profiles, protein-protein interaction networks, and biomedical literature. We benchmark each approach across three classes of tasks: predicting individual gene attributes, characterizing paired gene interactions, and assessing gene set relationships while trying to control for data leakage. Overall, we find that literature-based embeddings deliver superior performance across prediction tasks, sequence-based models excel in genetic interaction predictions, and expression-derived representations are well-suited for disease-related associations. Interestingly, network embeddings achieve similar performance to literature-based embeddings on most tasks despite using significantly smaller training sets. The type of training data has a greater influence on performance than the specific embedding construction method, with embedding dimensionality having only minimal impact. Our benchmarks clarify the strengths and limitations of current gene embeddings, providing practical guidance for selecting representations for downstream biological applications.

bioinformatics↗

bioRxiv2025

Automatically Defining Protein Words for Diverse Functional Predictions Based on Attention Analysis of a Protein Language Model

Understanding the relationship between protein sequence and function remains a longstanding challenge in bioinformatics, and to date the lions share of related tools parse proteins at the domain or motif levels. Here, we define "protein words" as an alternative to "motif" for studying proteins and functional prediction applications. We first developed an unsupervised tool we term Protein Wordwise, which parses analyte protein sequences into protein words by analyzing attention matrices from a protein language model (PLM) through a community detection algorithm. We then developed a supervised sequence-function prediction model called Word2Function, for mapping protein words to GO terms through feature importance analysis. We compared the prediction performance of our protein word-based toolkit with a motif-based method (PROSITE) for multiple protein function datasets. We also assembled a functionally diverse data resource we term PWNet to support evaluation of protein words for predicting functional residues across 10 tasks (e.g., diverse biomolecular binding, catalysis, and ion-channel activity). Our toolkit outperforms PROSITE in all the examined datasets and tasks. By abandoning domains and instead using attention matrices from a PLM for automatic, systematic, and annotation-agnostic parsing of proteins, our toolkit both outperforms currently available tools for functional annotations at the residue and whole-protein levels and suggests innovative forms of protein analysis well-suited to the post-AlphaFold era of biochemistry.

bioinformatics↗

bioRxiv2025

Extensive genome evolution distinguishes maize within a stable tribe of grasses

Over the last 20 million years, the Andropogoneae tribe of grasses has evolved to dominate 17% of global land area. Domestication of these grasses in the last 10,000 years has yielded our most productive crops, including maize, sugarcane, and sorghum. The majority of Andropogoneae species, including maize, show a history of polyploidy - a condition that, while offering the evolutionary advantage of multiple gene copies, poses challenges to basic cellular processes, gene expression, and epigenetic regulation. Genomic studies of polyploidy have been limited by sparse sampling of taxa in groups with multiple polyploidy events. Here, we present 33 genome assemblies from 27 species, including chromosome-scale assemblies of maize relatives Zea and Tripsacum. In maize, the after-effects of polyploidy have been widely studied, showing reduced chromosome number, biased fractionation of duplicate genes, and transposable element (TE) expansions. While we observe these patterns within the genus Zea, 12 other polyploidy events deviate significantly. Those tetraploids and hexaploids retain elevated chromosome number, maintain nearly complete complements of duplicate genes, and have only stochastic TE amplifications. These genomes reveal variable outcomes of polyploidy, challenging simple predictions and providing a foundation for understanding its evolutionary implications in an ecologically and economically important clade.

evolutionary biology↗

bioRxiv2025

Elucidation of the biosynthetic pathway of reserpine

Reserpine is a landmark natural product that has profoundly influenced our understanding of neurotransmitter biology and cardiovascular medicine. Its complex structure, featuring a unique C3 {beta}-configuration and five consecutive chiral centers, has inspired generations of synthetic chemists to develop innovative strategies for its construction. However, the biosynthetic logic underlying natures assembly of this intricate molecule has remained elusive. Here, we decipher the biosynthetic pathway of reserpine in Rauvolfia verticillata, revealing that -configured strictosidine serves as the biosynthetic precursor. The crucial C3 {beta}-configuration is established through a two-step enzymatic epimerization, orchestrated by a flavin-dependent oxidase and a NADPH-dependent reductase. The consecutive chiral centers are constructed through coordinated action of distinct enzyme families. Through the identification of eight biosynthetic enzymes, including those catalyzing late-stage methoxylation, we successfully reconstituted the biosynthesis of rauvomitorine G, a key intermediate in reserpine formation. This work unveils natures elegant approach to stereoselective synthesis of complex alkaloids and provides valuable biocatalytic tools for molecular functionalization.

biochemistry↗

bioRxiv2025

VitisC: Visualizing interested target via integrated scaffold of cytoophidium

Cryo-electron microscopy (cryo-EM) single-particle analysis has become a widely used technique for high-resolution structural determination of biological macromolecules and complexes. However, the determination of the structure of small molecule proteins remains a limitation of this technology. To address this issue, here we develop a novel approach termed Visualizing interested target via integrated scaffold of cytoophidium (VitisC). We use a filamentous structure formed by Escherichia coli CTP synthase (CTPS) as the scaffold, termed the scaffold of cytoophidium. Through artificial design and modification, small proteins can be attached to this symmetrical scaffold, which is very suitable for cryo-EM imaging. The formation conditions for stable filament structures of the fusion protein are optimized in vitro, and the three-dimensional structure of the fusion protein is reconstructed using cryo-EM single-particle analysis, achieving an overall resolution of 3.39 [A]. Therefore, cryo-EM is successfully applied to visualize small proteins. VitisC not only demonstrates the feasibility of employing cytoophidia as scaffolds, but also provides an approach for high-resolution structural analysis of small proteins using Cryo-EM.

biochemistry↗

bioRxiv2024

Electron-density informed effective and reliable de novo molecular design and lead optimization with ED2Mol

Generative drug design opens new avenues for discovering novel compounds within the vast chemical space rather than conventional screening against limited compound libraries. However, the practical utility of the generated molecules is frequently constrained, as many designs prioritize a narrow range of pharmacological properties while neglecting physical reliability, which hinders the success rate of subsequent wet-lab evaluations. To address this, we propose ED2Mol, a deep learning-based approach that leverages fundamental electron density information to improve de novo molecular generation and lead optimization. The extensive evaluations across multiple benchmarks demonstrate that ED2Mol surpasses existing methods in terms of generation success rate and >97% physical reliability. It also facilitates automated lead optimization that is not fully implemented by other methods using fragment-based strategies. Furthermore, ED2Mol exhibits generalizability to more challenging, unseen allosteric pocket benchmarks, attaining consistent performance in both de novo molecule generation and lead optimization. More importantly, ED2Mol has been applied to various real-world essential targets, successfully identifying wet-lab validated bioactive compounds, ranging from FGFR3 orthosteric inhibitors to CDC42 allosteric inhibitors and GCK allosteric activators. The directly generated binding modes of these compounds with target proteins are close to predictions through molecular docking and further validated via the X-ray co-crystal structure. All these results highlight ED2Mols potential as a useful tool in realistic drug design with enhanced effectiveness, physical reliability, and practical applicability.

bioinformatics↗

bioRxiv2024

Chemostat culturing reduces fecal eukaryotic virus load and delays diarrhea after virome transplantation

Fecal virome transfer (FVT) shows promise in reducing necrotizing enterocolitis (NEC), likely due to donor bacteriophages preventing the gut dysbiosis preceding disease. However, concurrent transfer of eukaryotic viruses may carry a risk of infection for the recipient. To increase safety, we investigated chemostat propagation as a method to eliminate eukaryotic viruses from donor feces while maintaining a diverse and reproducible bacteriophage community. Donor feces was collected from healthy suckling piglets and inoculated into a fermenter containing growth media supplemented with lactose and milk oligosaccharides (MOs). During continuous medium exchange (20% volume/h), dilution significantly reduced eukaryotic viruses. Viral richness was concurrently reduced although still preserving a stable community of 200-250 bacteriophages. Inclusion of MOs in the medium ensured higher bacterial richness and a bacterial community closer resembling donor feces. Fecal Lactobacillaceae bacteria were lost during cultivation but partially replaced by members of the Bacteroidota phylum in MO-supplemented cultures, accompanied by phages predicted to have Parabacteroides as host. After cultivation, virus-like particles (VLPs) were isolated, and their ability to reduce NEC incidence tested in vivo. Preterm piglets were delivered by cesarean section and received either the lactose- or MO-propagated viromes by oral route (n = 14-15/group). These were compared with groups receiving the same dose of donor fecal virome (1010 VLPs/kg) or vehicle control. The piglets were subsequently fed infant formula for 96 hours followed by euthanasia and tissue sampling. Both chemostat-propagated viromes effectively mitigated diarrhea compared to the donor virome. The donor virome partially engrafted in recipients and led to higher levels of Lactobacillaceae bacteria and Lactobacillaceae targeting phages. However, these signatures were lost in recipients of chemostat-propagated viromes, and only minor microbiome effects and no NEC prevention were observed. To conclude, we provide in vivo proof-of-concept for chemostat propagation of fecal viruses as a means to deplete eukaryotic viruses and in turn reduce side effects in newborn virome recipients. However, chemostat culture conditions need further optimization to preserve the donor phageome.

microbiology↗

bioRxiv2024

Stacked Human Arterial Endothelial Cells Generate Atherosclerotic Fatty Streaks and Release Proinflammatory Cytokines

Fatty streaks are the first sign of atherosclerosis. They consist of lipid-containing foam cells, which were believed to be derived from the monocytes in the blood through the leaky endothelium, and from the vascular smooth muscle cells migrating into the intima from the media. Here, we showed that fatty streaks can also be formed by the stacked human arterial endothelial cells (HAECs) cultured in vitro. Via SEM we revealed a novel cell phenotype (coralthelial) that forms a streak/coral-like structure. We observed accumulation of lipids in the coralthelial cell and increased Golgi and coat protein II markers in its nucleus. Additionally, proinflammatory cytokines were upregulated in these cells, likely due to Golgi nuclear translocation and subsequently increased expression of the ribosomal protein RPL23 in the nucleus. We demonstrated, for the first time, that the atherosclerotic fatty streak-like structure can be generated from the stacked HAECs, which also create a proinflammatory microenvironment. Significance StatementOur work presents a novel perspective on atherosclerotic fatty streak formation, a critical early event in atherosclerosis development. We demonstrate, for the first time, that human arterial endothelial cells (HAECs) can transform into a novel phenotype, termed "coralthelial cells". These cells contribute to fatty streak formation, and produce proinflammatory cytokines through the relocation of RPL23 with the Golgi apparatus to the nucleus. This finding provides a new cellular mechanism by which endothelial cells initiate atherosclerosis, independent of traditional monocyte-derived foam cells. By enriching established paradigms, our research not only opens new avenues for therapeutic intervention targeting endothelial cells but also enhances understanding of vascular diseases and provides potential diagnostic and prognostic markers for atherosclerosis.

cell biology↗

bioRxiv2024

Activating p53Y220C with a Mutant-Specific Small Molecule

TP53 is the most commonly mutated gene in cancer, but it remains recalcitrant to clinically meaningful therapeutic reactivation. We present here the discovery and characterization of a small molecule chemical inducer of proximity that activates mutant p53. We named this compound TRanscriptional Activator of p53 (TRAP-1) due to its ability to engage mutant p53 and BRD4 in a ternary complex, which potently activates mutant p53 and triggers robust p53 target gene transcription. Treatment of p53Y220C expressing pancreatic cell lines with TRAP-1 results in rapid upregulation of p21 and other p53 target genes and inhibits the growth of p53Y220C-expressing cell lines. Negative control compounds that are unable to form a ternary complex do not have these effects, demonstrating the necessity of chemically induced proximity for the observed pharmacology. This approach to activating mutant p53 highlights how chemically induced proximity can be used to restore the functions of tumor suppressor proteins that have been inactivated by mutation in cancer.

cancer biology↗

bioRxiv2024

RIG-I and MDA5 cooperatively recognize the DENV replicative-form dsRNA to activate innate immunity

RIG-I like receptors (RLRs) are a family of cytosolic RNA sensors that sense RNA virus infection to activate innate immune response. It is generally believed that different RNA viruses are recognized by either RIG-I or MDA5, two important RLR members, depending on the nature of pathogen-associated molecular patterns (PAMPs) that are generated by RNA virus replication. Dengue virus (DENV) is an important RNA virus causing serious human diseases. Despite extensive investigations, the molecular basis of the DENV PAMP recognized by the host RLR has been poorly defined, and which RLR is involved in sensing the DENV PAMP remains controversial. Here, we demonstrated that the DENV infection-induced interferon response is dependent upon both RIG-I and MDA5, with RIG-I playing a predominant role. Next we purified the DENV PAMP RNA from the DENV-infected cells, and demonstrated that the purified DENV PAMP is viral full-length double-stranded RNA bearing 5ppp modifications, likely representing the viral replicative-form RNA. Finally, we confirmed the nature of the DENV PAMP by reconstituting the viral replicative-form RNA from in vitro synthesized DENV genomic RNA. In conclusion, our work not only defined the molecular basis of the RLR-PAMP interaction during DENV infection, but also revealed the previously underappreciated recognition of the distinct moiety of same PAMP by different RLRs in innate immunity against RNA viruses. ImportanceThe molecular interaction between PAMPs and RLRs plays a crucial role in innate immune response against the RNA virus infection. To our knowledge, the exact molecular basis of the DENV PAMPs and which RLR member (RIG-I or MDA5) is involved in this recognition remain controversial. In this study, we demonstrated that the DENV PAMP is likely DENV replicative-form RNA, a double-stranded RNA. RIG-I and MDA5 can sense different moieties of this DENV PAMP to active innate immune response. Our work not only clarified which RLR and what viral PAMP are involved in innate immune sensing of DENV infection, but also revealed previously underappreciated recognition of the same PAMPs by different RLRs in innate immunity against RNA viruses.

microbiology↗

bioRxiv2024

Discovery of electrophilic degraders that exploit SNAr chemistry

Targeted covalent inhibition (TCI) and targeted protein degradation (TPD) have proven effective in pharmacologically addressing formerly undruggable targets. Integration of both methodologies has resulted in the development of electrophilic degraders where recruitment of a suitable E3 ubiquitin ligase is achieved through formation of a covalent bond with a cysteine nucleophile. Expanding the scope of electrophilic degraders requires the development of electrophiles with tempered reactivity that enable selective ligase recruitment and reduce cross-reactivity with other cellular nucleophiles. In this study, we report the use of chemical moieties that enable nucleophilic aromatic substitution (SNAr) reactions in the rational design of electrophilic protein degraders. Appending an SNAr covalent warhead to several preexisting small molecule inhibitors transformed them into degraders, obviating the need for a defined E3 ligase recruiter. The SNAr covalent warhead is versatile; it can recruit various E3 ligases, including DDB1 and CUL4 associated factor 11 (DCAF11), DDB1 and CUL4 associated factor 16 (DCAF16), and possibly others. The incorporation of an SNAr covalent warhead into the BRD4 inhibitor led to the discovery of degraders with low picomolar degradation potency. Furthermore, we demonstrate the broad applicability of this approach through rational functional switching from kinase inhibitors into potent degraders.

biochemistry↗

bioRxiv2024

Deleting PTEN, but not SOCS3 or myelin inhibitors, robustly boosts BRAF-elicited intraspinal regeneration of peripheral sensory axons

Primary sensory axons fail to regenerate into the spinal cord after dorsal root (DR) injury, resulting in persistent sensory deficits. This regenerative failure occurs at the dorsal root entry zone (DREZ), the CNS-PNS interface where injured sensory axons encounter both extrinsic inhibitory cues and a limited intrinsic growth state. Although several approaches have promoted partial DR regeneration across the DREZ, sustained long-distance regeneration, particularly of large-diameter myelinated axons, remains a major challenge. We previously showed that induced expression of constitutively active B-RAF (kaBRAF) increases the regenerative competence of injured adult DRG neurons. Here, we tested whether robust intraspinal regeneration after cervical DR injury could be achieved by selective kaBRAF expression alone or in combination with removal of myelin-associated inhibitors or deletion of neuron-intrinsic growth suppressors, PTEN or SOCS3. kaBRAF promoted reproducible but limited regeneration across the DREZ and did not produce significant functional recovery by two months. Additional deletion of Nogo, MAG, and OMgp produced only a modest improvement in kaBRAF-mediated regeneration. Deletion of PTEN or SOCS3, either alone or together, failed to promote meaningful growth across the DREZ. In contrast, PTEN deletion dramatically enhanced kaBRAF-mediated regeneration, enabling many axons to penetrate the DREZ and grow deep into the spinal cord, whereas SOCS3 deletion provided little additional benefit. These findings identify combined activation of BRAF-MEK-ERK and PI3K-Akt-mTOR signaling as a powerful strategy for stimulating robust intraspinal regeneration of injured DR axons.

neuroscience↗