Biology subjects

Shukla, N.

Publications and source records attributed to Shukla, N..

At least 19 recordsLinked to original sources

bioRxiv2026

Massively parallel characterization reveals context-dependent and non-additive regulatory effects of closely spaced variant pairs

Precise control of gene expression relies in part on cis-regulatory elements (CREs), including enhancers. Genetic variation within enhancers can alter their regulatory activity and contribute to variation in gene expression, yet the effects of multiple nearby variants within the same enhancer remain poorly understood. To address this, we designed a massively parallel reporter assay (MPRA) to test the regulatory effect of 7,285 pairs of close-proximity single-nucleotide variants (SNVs) selected from blood-specific and broadly active enhancers. To enrich for functionality, we required at least one variant in each pair to be annotated as an eQTL in eQTLGen dataset. We measured the regulatory activity of all four haplotypes in K562 leukemia cells, where 57% of tested variant pairs had at least one derived haplotype that differed significantly in activity from the ancestral haplotype. The effects of individual variants frequently depended on the allelic background provided by the neighboring variant, with some variants showing opposite effects in different allelic backgrounds. Among a smaller, high-confidence subset selected for analysis of additivity, 59% (105/178) of variant pairs showed non-additive effects, and non-additive pairs were located closer together than additive pairs. Among pairs in which both single-derived haplotypes increased activity, the double-derived haplotype generally showed a smaller effect than expected under additivity. Together, our results demonstrate that nearby variants within the same enhancer can jointly shape regulatory activity and highlight the importance of considering local allelic context when interpreting the functional effects of regulatory variation.

genomics↗

bioRxiv2026

PARP1 inhibition regulates tumor progression through modulation of RhoGDIα and vimentin in triple negative breast cancer

Background and PurposePARP inhibitors have been evaluated in clinical trials for several cancers and Olaparib is FDA approved for treating BRCA deficient ovarian cancer. Numerous reports have suggested Poly(ADP-ribose) polymerase1(PARP1) overexpression in a variety of cancers including breast carcinomas and proposed the role of PARP1 in metastasis. However, the mechanism of PARP1 in regulating metastatic process in BRCA proficient and deficient TNBC is not studied thoroughly. In this study, we propose that PARP1 mediated breast carcinoma progression is gene transcription mediated, where it regulates several steps of pro-metastasis. Experimental ApproachPARP inhibitors effect on metastasis was monitored by migration and invasion assay, modulation in protein expression was assessed by proteomic analysis and further confirmed by immunoblotting. Chromatin immunoprecipitation was performed to study the transcriptional role of PARP1. Ectopic expression and siRhoGDI, and immunofluorescence assessed the cytoskeleton changes. PARP inhibitor was administered in xenograft mice to study metastasis. Immunohistochemical analysis was done on patient and mice tissues. Key resultsBreast cancer cells exhibited reduced migration and invasion due to PARP1 inhibition. PARP1 regulates expression of vimentin and RhoGDI and hence cytoskeletal rearrangement causing a change in migrating potential of a cell. Metastasis in mice was reduced upon PARP inhibition. PARP1 was identified to be a novel transcriptional regulator of RhoGDI. Furthermore, RhoGDI ectopic expression substantiated the PARP inhibitor effects, suggesting the PARP inhibitor downstream signaling to be mediated through RhoGDI. Conclusions and ImplicationsWe identified a novel aspect of PARP1 as promoter of metastasis via transcriptional regulation of RhoGDI. Assessing RhoGDI levels in TNBC patients might be useful to predict sensitivity to PARP inhibitors.

cancer biology↗

bioRxiv2026

Electrostatically Assembled Layer-by-Layer Plasmonic Implant for Combination Therapy against Multidrug-Resistant Chronic Wound Biofilms

Although persistent infection from chronic wound lowers the efficacy of single therapy; But combination therapy with prolonged drug release have shown promising effect, such as elimination of heavy bacterial film and multi/single drug resistance with minimal side effects. One such breakthrough is multilayered scaffold that are chemically and physiologically stable. To achieve this objective, we demonstrated construction of layer-by-layer (LBL) assembly aligned by alternate deposition of (PEI/PSS and PAA/PSS) based on electrostatic force. These films exhibited loading of Ibu and gen which can be altered depending on different parameter such dipping time, pH and number of layers. Briefly, gen was encapsulated onto PPGNRs, as GNRs have good stability and their antibacterial properties can be enhanced by tunning surface upon adding chemical drugs. Such functionalized GNRs showed excellent photo thermal property which assisted controlled release of gen via deconstruction of thin layers, whereas burst release of ibu. Furthermore, complete disruption of bacterial colonies when combined with near infrared irradiation (NIR). The formed LBL endowed the great healing capability, controlled antibiotic release solve the problems of bacterial resistance due to synergistic effect. Taken together, the antibacterial, cytocompatibility, and stimuli responsive characteristics of this robust multilayer assembly can be promising multifunctional drug delivery system in different medical aliments.

microbiology↗

bioRxiv2026

Simultaneous Cancer Treatment with Photothermal Therapy andChemotherapy using Gold nanorods coated with Methotrexate conjugatedHyaluronic acid

Upon near-infrared (NIR) irradiation, combined treatment comprising of photothermal therapy (PTT) and chemotherapy (CHT) offers synergistic effects by inducing localized heat to intended tumor sites and simultaneously allowed delivering drugs thus to minimize undesired side-effects but enhance cytotoxic therapies. In this study we developed a novel platform that enables simultaneously to respond light stimuli with localized heat and released drugs using drug contained gold nanorods (GNRs). Methotrexate (MTX), a model anticancer drug is attached through hydrolytic ester bonding to targeting molecular hyaluronic acid (HA) that is coated onto GNRs. Based on the rationale, HA provides a good scaffold for high biocompatibility to shield risky GNRs, targeting for a CD44 receptor, and easy chemical binding of drugs. Upon a single light irradiation, MTX-HA functionalized GNRs (MTX-HA @GNRs) provide localized heat to cancer areas for PTT and the elevated temperature accelerates hydrolytic cleavage of the ester bond onto GNRs in physiological condition for CHT, ultimately releasing MTX to cells. In contrast to previous combination therapies that do not concurrently offer heat and drugs upon light stimuli, our NIR triggered CHT with PTT provides clinically effective options with combinatorial treatment that possesses high efficacy resulted in in vitro tests. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=159 SRC="FIGDIR/small/719030v1_figsh1.gif" ALT="Figure 1"> View larger version (84K): org.highwire.dtl.DTLVardef@f215f3org.highwire.dtl.DTLVardef@17f3016org.highwire.dtl.DTLVardef@12e265borg.highwire.dtl.DTLVardef@d85442_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOScheme 1.C_FLOATNO Schematic illustration of our nanoplatform a) The light responsive combinational therapy using GNRs scaffold for photo thermal therapy and chemotherapy b) The formation of TGNRs@RHO.B-HA and their light responsive mechanism with active CD44 receptor binding affinity c) light triggered hydrolytic release of model drug Rhodamine.B from TGNRs@RHO.B-HA. C_FIG

pharmacology and toxicology↗

bioRxiv2026

Genome-wide mapping of DCP2-dependent 5' cap footprints in Arabidopsis thaliana

mRNA decapping mediated by DCP2 is a key mechanism controlling RNA stability and gene expression in eukaryotes, including plants. Despite its central role in regulating plant development and stress responses, the repertoire of mRNA 5 caps targeted by DCP2 remains undefined. Here, we combined in vitro decapping treatment with 5-end enriched and full-length transcriptome sequencing of DCP2-deficient mutants to comprehensively characterize the mRNA capping landscape in Arabidopsis thaliana. We mapped over 13,000 high-confidence capped transcripts at nucleotide resolution, revealing distinct 5 cap signatures in both wild type and dcp2 seedlings. Most caps were localized near annotated transcription start sites, validating the accuracy of our approach. Loss of DCP2 led to a substantial accumulation of capped mRNAs, including 275 capped transcripts originating from previously unannotated loci. It also increased prevalence of multi-capped genes highlighting the role of DCP2-mediated decapping in removing unwanted transcripts. Integration of these data with degradome resources revealed that targets of co-translational and cytosolic XRN4-dependent decay, as well as of nonsense-mediated decay, were enriched among capped mRNAs specifically accumulated in dcp2. These findings suggest that mRNA degradation in these decay pathways is mediated through decapping. In addition, this study provides a valuable resource for transcript annotation and isoform-aware analysis of RNA turnover. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=82 SRC="FIGDIR/small/709597v1_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@3569a2org.highwire.dtl.DTLVardef@aa2ca3org.highwire.dtl.DTLVardef@58a27forg.highwire.dtl.DTLVardef@1147350_HPS_FORMAT_FIGEXP M_FIG C_FIG

plant biology↗

bioRxiv2025

Lift&Add - rapid and robust addition of new species to alignments of conserved non-coding sequences

Identifying sequence constraint across long evolutionary distances is a powerful method for the discovery of functional genomic sequences, especially putative non-coding elements. Conserved elements have been a mainstay of comparative genomic research, and can be further investigated for specific-specific sequence acceleration to dissect the genetic basis of trait evolution. The conclusions of these comparative genomic studies are however contingent in on the number and range of species included in this phylogenetic analysis. One group of species that has been largely under-represented in genomic comparisons are the marsupials, due to the dearth of marsupial genomes in most publicly available whole-genome alignments. In this study, we firstly showed how biased phylogenetic distributions can profoundly affects estimations of conservation/acceleration with a focus on the marsupials. Then we present a bioinformatic workflow that rapidly enabled us to map 13,287 vertebrate conserved elements--a majority of which were intergenic--identified from the 60-species whole-genome alignment of vertebrates (containing only 4 marsupials) to up to 12 new marsupial genomes ("Lift"). Following this, we combined these new marsupials sequences back to multiple species alignments of these conserved elements ("Add"). Lastly, we demonstrate with our test dataset how expanding phylogenetic breadth can change the conclusions of a comparative genomic analysis.

genomics↗

bioRxiv2025

Post-transcriptional regulation of meiotic transcripts by the RNA binding protein CDM1 is associated with cytoplasmic condensate assemblies

The transition from diploid to haploid life phases requires extensive reprogramming of gene expression that drive meiotic cell division and the differentiation of haploid forms. A hallmark of meiosis is widespread post-transcriptional regulation, including delayed translation that ensures timely protein production at specific stages. Here, we identify a mechanism controlling the translation of meiotic transcripts in Arabidopsis pollen mother cells, mediated by CALLOSE DEFECTIVE MICROSPORES1 (CDM1). We show that CDM1 affects several meiotic processes, including chromosome pairing, condensation, and cytokinesis. CDM1 forms dynamic, meiosis specific cytoplasmic foci that associate with components of processing bodies and stress granules, giving rise to three-phase condensate assemblies. Biochemical and cellular analyses reveal that CDM1 is an RNA-binding protein with an intrinsic ability to form ribonucleoprotein condensates. Furthermore, we demonstrate that CDM1 binds mRNAs expressed in prophase I and represses their translation until later meiotic stages, coinciding with the disassembly of CDM1 condensates. These findings establish CDM1 as a key post-transcriptional regulator that fine-tunes the expression of meiotic genes to ensure proper progression of microsporogenesis.

plant biology↗

bioRxiv2025

Dissecting functional regulatory convergence over 160 million years of therian evolution

Understanding the molecular mechanisms underpinning convergent traits can provide insight into the predictability of the evolutionary process. The thylacine, an extinct marsupial carnivore, has been long known to have a very similar craniofacial morphology to that of eutherian canids, despite having diverged{approx} 160 million years ago. Using a massively parallel reporter assay (MPRA), we tested the regulatory potential of a set of previously identified highly conserved craniofacial enhancers that showed convergent sequence acceleration in thylacine and wolf (TWARs). We compared orthologous sequences from six different taxa, including outgroup taxa with non-convergent craniofacial phenotypes (Tasmanian devil and giant panda) and ancestral reconstructions for marsupial and placental carnivores (Dasyuromorphia and Carnivora). Dense 10bp tiling allowed us to thoroughly examine features associated with activity, including percentage GC content and transcription factor binding motifs turnover. We identified marked conservation of levels and patterns of regulatory activity across all six taxa, as well as multiple cases of differentially active TWARs within each clade, with both thylacine and wolf driving functional divergence. However, evidence of convergent divergence was limited to a set of neighbouring TWARs near the neural crest gene Phox2b - one of which exhibited reduced activity in the wolf, and the other in the thylacine. Ultimately our findings suggest that shared gene regulatory potential is not a feature of these convergently accelerated regions in the thylacine and wolf.

genomics↗

bioRxiv2025

SMG7 and eIF4A constitute a homeostatic module controlling P-body condensation and function of Meiotic bodies

Processing bodies (P-bodies) are ribonucleoprotein condensates that regulate RNA processing and storage. Although present constitutively in most cells, their size and composition dynamically change in response to developmental and environmental cues. However, mechanisms governing P-body assembly and remodelling remain poorly understood. Here we show that in Arabidopsis, SMG7 interacts with the eIF4A helicases and recruits them to P-bodies. eIF4As limit P-bodies condensation and also restrict stress granule (SG) formation under heat stress. We further identify meiotic (M-)bodies as composite RNP granules with a P-body core surrounded by a SG-like shell. The SMG7-eIF4A module regulates the recruitment of the meiosis-specific protein TDM1 into M-bodies, influencing meiotic exit and plant reproduction. Our findings suggest that SMG7 functions as an adaptor protein that recruits client proteins into P-bodies and, together with eIF4A, forms a regulatory module that regulates P-body composition and maintains their size homeostasis.

cell biology↗

bioRxiv2025

Mapping the gene regulatory landscape of archaic hominin introgression in modern Papuans

Interbreeding between anatomically modern humans and archaic hominins has contributed to the genomes of present-day human populations. However, our understanding of the specific gene regulatory consequences of Neanderthal, and particularly, Denisovan introgression is limited. Here, we used a massively parallel reporter assay to investigate the regulatory effects of 25,869 high-confidence introgressed SNPs segregating in present-day individuals of Papuan genetic ancestry in immune cell types. Overall, 8.22% of Denisovan and 8.58% of Neanderthal sequences showed active regulatory activity, and 9.22% of these displayed differential activity between alleles. We examined the properties of active and differentially active sequences, and found no impact of introgressed allele frequency on the probability of activity, but do observe an association with distance to the nearest transcription start site. Differential activity was also associated with differential transcription factor binding. Genes predicted to be regulated by differentially active sequences included IFIH1 and TNFAIP3, key immune genes and known examples of archaic introgression. Overall, this work provides insight into the regulatory activity of archaic variants in Papuan populations and, more broadly, the contribution of archaic introgression in shaping modern human genetic diversity.

evolutionary biology↗

bioRxiv2025

Kozak sequence libraries for characterizing transgenes across expression levels

Typical mammalian overexpression systems test protein sequence variants with little control over expression levels and steady-state protein abundances, hindering interpretations of how protein sequence and expression converge to yield phenotypic outcomes. We explored the translation initiation sequence, commonly referred to as the Kozak sequence, as a means to modulate protein steady-state abundance and cellular function. We performed sort-seq on a randomized library of the 6 nucleotides preceding the start codon, amounting to 4,042 sequences. Calibrating the scores revealed a ~100-fold range of protein steady-state abundances possible through manipulation of the Kozak sequence. We identified human germline variants with predicted expression-reducing Kozak substitutions in disease-associated genes. Modulating the cell surface abundance of the host cell receptor ACE2 controlled the rate at which those cells became infected by SARS-like coronavirus spike pseudotyped particles. We demonstrated the potential of the approach by simultaneously testing Kozak libraries with a small panel of coding variants for ACE2 and STIM1. This approach lays the methodological groundwork for linking the causal relationships between protein sequence, abundance, and functional outcome.

genetics↗

bioRxiv2025

TOR and heat shock response pathways regulate peroxisome biogenesis during proteotoxic stress

Peroxisomes are versatile organelles mediating energy homeostasis and redox balance. While peroxisome dysfunction is linked to numerous diseases, the molecular mechanisms and signaling pathways regulating peroxisomes during cellular stress remain elusive. Using yeast, we show that perturbations disrupting protein homeostasis including loss of ER or cytosolic chaperone function, impairments in ER protein translocation, blocking ER N-glycosylation, or reductive stress, cause peroxisome proliferation. This proliferation is driven by increased de novo biogenesis from the ER as well as increased fission of pre-existing peroxisomes, rather than impaired pexophagy. Notably, peroxisome biogenesis is essential for cellular recovery from proteotoxic stress. Through comprehensive testing of major signaling pathways, we determine this response to be mediated by activation of the heat shock response and inhibition of Target of Rapamycin (TOR) signaling. Finally, the effects of proteotoxic stress and TOR inhibition on peroxisomes are also captured in human fibroblasts. Overall, our findings reveal a critical and conserved role of peroxisomes in cellular response to proteotoxic stress.

cell biology↗

bioRxiv2024

Role of CCK1 receptor in metabolic benefits of intestinal enteropeptidase inhibition in mice

Enteropeptidase (EP; enterokinase) is a serine protease that regulates intestinal protein digestion by converting trypsinogen into active trypsin, and thus initiates activation of the pancreatic zymogen cascade. Chronic inhibition of EP and trypsin (EP/T) with camostat (Foipan, FOY-305) or its active metabolite (FOY-251) causes weight loss in obese mice by reducing intestinal protein absorption and suppression of food intake, however, the mechanisms leading to appetite suppression are not well understood. We tested the hypothesis that cholecystokinin (CCK) signaling mediates the anorectic effects of EP/T inhibition using a CCK1R inhibitor (loxiglumide) or CCK1R knockout (KO) mice. Acute treatment with loxiglumide was able to partially reverse FOY-251-induced gallbladder contraction and delayed gastric emptying in mice. Chronic co-administration of loxiglumide reversed FOY-251 mediated effects on food intake and metabolism in diet-induced obese (DIO) mice. Chronic dosing of FOY-251 caused similar reductions in food intake but greater weight loss in CCK1R KO mice compared to wildtype (WT) mice, primarily due to fat mass loss. Pair fed (PF) groups revealed food intake-dependent and -independent mechanisms of weight loss by FOY-251. Notably, FOY-251 treatment induced sustained weight loss, whereas body weight loss rebounded in PF animals. In CCKR1 KO mice, FOY-251 caused greater weight loss, and increased protein calorie loss relative to that in WT mice, while having no effect on glycemic control or FGF21. Hence, CCK1R-dependent and - independent mechanisms modulate the metabolic effects of EP/T inhibition and may play a role in maintaining weight loss by this mechanism.

pharmacology and toxicology↗

bioRxiv2024

Emergence of Dip2-mediated Specific DAG-based PKC Signalling Axis in Eukaryotes

Diacylglycerols (DAGs) are used for metabolic purposes and are tightly regulated secondary lipid messengers in eukaryotes. DAG subspecies with different fatty-acyl chains are proposed to be involved in the activation of distinct PKC isoforms, resulting in diverse physiological outcomes. However, the molecular players and the regulatory origin for fine-tuning the PKC pathway are unknown. Here, we show that Dip2, a conserved DAG regulator across Fungi and Animalia, has emerged as a modulator of PKC signalling in yeast. Dip2 maintains the level of a specific DAG subpopulation, required for the activation of PKC-mediated cell wall integrity pathway. Interestingly, the canonical DAG-metabolism pathways, being promiscuous, are decoupled from PKC signalling. We demonstrate that these DAG subspecies are sourced from a phosphatidylinositol pool generated by the acyl-chain remodelling pathway. Furthermore, we provide insights into the intimate coevolutionary relationship between the regulator (Dip2) and the effector (PKC) of DAG-based signalling. Hence, our study underscores the establishment of Dip2-PKC axis about 1.2 billion years ago in Opisthokonta, which marks the rooting of the first specific DAG-based signalling module of eukaryotes.

cell biology↗

bioRxiv2024

Automated, image-based quantification of peroxisome characteristics with perox-per-cell

perox-per-cell automates cumbersome, image-based data collection tasks often encountered in peroxisome research. The software processes microscopy images to quantify peroxisome features in yeast cells. It uses off-the-shelf image processing tools to automatically segment cells and peroxisomes and then outputs quantitative metrics including peroxisome counts per cell and spatial areas. In validation tests, we found that perox-per-cell output agrees well with manually-quantified peroxisomal counts and cell instances, thereby enabling high-throughput quantification of peroxisomal characteristics. The software is available at https://github.com/AitchisonLab/perox-per-cell

bioinformatics↗

bioRxiv2024

Pseudotyped virus infection of multiplexed ACE2 libraries reveals SARS-CoV-2 variant shifts in receptor usage

Pairwise compatibility between virus and host proteins can dictate the outcome of infection. During transmission, both inter- and intraspecies variabilities in receptor protein sequences can impact cell susceptibility. Many viruses possess mutable viral entry proteins and the patterns of host compatibility can shift as the viral protein sequence changes. This combinatorial sequence space between virus and host is poorly understood, as traditional experimental approaches lack the throughput to simultaneously test all possible combinations of protein sequences. Here, we created a pseudotyped virus infection assay where a multiplexed target-cell library of host receptor variants can be assayed simultaneously using a DNA barcode sequencing readout. We applied this assay to test a panel of 30 ACE2 orthologs or human sequence mutants for infectability by the original SARS-CoV-2 spike protein or the Alpha, Beta, Gamma, Delta, and Omicron BA1 variant spikes. We compared these results to an analysis of the structural shifts that occurred for each variant spikes interface with human ACE2. Mutated residues were directly involved in the largest shifts, although there were also widespread indirect effects altering interface structure. The N501Y substitution in spike conferred a large structural shift for interaction with ACE2, which was partially recreated by indirect distal substitutions in Delta, which does not harbor N501Y. The structural shifts from N501Y greatly influenced the set of animal orthologs the variant spike was capable of interacting with. Out of the thirteen non-human orthologs, ten exhibited unique patterns of variant-specific compatibility, demonstrating that spike sequence changes during human transmission can toggle ACE2 compatibility and potential susceptibility of other animal species, and cumulatively increase overall compatibilities as new variants emerge. These experiments provide a blueprint for similar large-scale assessments of protein compatibility during entry by diverse viruses. This dataset demonstrates the complex compatibility relationships that occur between variable interacting host and virus proteins.

genetics↗

bioRxiv2023

In silico approaches to identify the role of lncRNAs in Prostate cancer and Androgen receptor-targeted proteins

Long non-coding RNA (lncRNAs) are known to have a role in pathogenesis of a broad spectrum of malignancies.These are found to have a significant role as signal transduction mediators in cancer signaling pathways. Prostate Cancer (PCa) is emerging with increasing cases worldwide even as advanced approaches in clinical diagnosis and treatment of PCa are still challenging to address. To enhance patient stratification, there is an indefatigable need to understand risk that can allow new approaches of treatment based on prognosis. While PCa is known to have mediated androgen receptor (AR) stimulation, the latter plays a key role in regulating transcription of genes via nuclear translocation which in turn leads to response to androgens. LncRNAs have been implicated in developing clinical diagnostic and prognostic biomarkers in a broad spectrum of cancers. In our present study, 12 lncRNAs identified from clinical samples from our erstwhile PCa patients were docked with PCa and AR targeted 36 proteins. We identified three lncRNAs, viz. SCARNA10, NPBWR1, ANKRD20A9P are common between the targeted proteins and discern that SCARNA10 lncRNA could serve as a prognostic signature for PCa and AR biogenesis. We also sought to check the coding potential of interfacial residues associated with lncRNA docking sites.x

bioinformatics↗

bioRxiv2023

Mutant Prion Protein Endoggresomes are Hubs for Local Axonal Organelle-Cytoskeletal Remodeling

Dystrophic axons comprising misfolded mutant prion protein (PrP) aggregates are a characteristic pathological feature in the prionopathies. These aggregates form inside endolysosomes -called endoggresomes-, within swellings that line up the length of axons of degenerating neurons. The pathways impaired by endoggresomes that result in failed axonal and consequently neuronal health, remain undefined. Here, we dissect the local subcellular impairments that occur within individual mutant PrP endoggresome swelling sites in axons. Quantitative high-resolution light and electron microscopy revealed the selective impairment of the acetylated vs tyrosinated microtubule cytoskeleton, while micro-domain image analysis of live organelle dynamics within swelling sites revealed deficits uniquely to the MT-based active transport system that translocates mitochondria and endosomes toward the synapse. Cytoskeletal and defective transport results in the retention of mitochondria, endosomes, and molecular motors at swelling sites, enhancing mitochondria-Rab7 late endosome contacts that induce mitochondrial fission via the activity of Rab7, and render mitochondria dysfunctional. Our findings point to mutant Pr Pendoggresome swelling sites as selective hubs of cytoskeletal deficits and organelle retention that drive the remodeling of organelles along axons. We propose that the dysfunction imparted locally within these axonal micro-domains spreads throughout the axon over time, leading to axonal dysfunction in prionopathies.

cell biology↗