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Kim, J. H.

Publications and source records attributed to Kim, J. H..

At least 55 records · Page 3Linked to original sources

The Mechanism of Dynamic Steady States in Lamellipodia

Lamellipodia are quasi-two-dimensional actin projections formed on the leading edge of the cell, playing an important role in sensing surrounding environments by forming focal adhesions. A branched actin network in the lamellipodia exhibits a stable, dynamic steady state characterized by a retrograde flow, which is attributed to a balance between network assembly at the leading edge and disassembly at the rear. Although the molecular players and architecture of the lamellipodia have been investigated extensively during recent decades, it still remains elusive how the dynamic steady state with continuous retrograde flow is achieved and robustly maintained. In this study, using an agent-based computational model, we probed how physical interactions between subcellular components in the lamellipodia lead to the dynamic steady state. We reproduced a steady retrograde flow induced by myosin activity and balance between network assembly and disassembly but hindered by resistances from adhesions formed on the underlying substrate. We demonstrated that different modes of dynamic steady states are possible, and that a network which failed to show the retrograde flow due to perturbations can be rescued by altering other factors. Our study provides insights into understanding how cells maintain the dynamic steady state of the lamellipodia in highly varying microenvironments.

biophysics↗

Disordered glass nanowire substrates produce in vivo-like astrocyte morphology revealed by optical diffraction tomography

Astrocytes, integral components of the central nervous system (CNS), fulfill crucial roles such as maintaining ion homeostasis, providing neuroprotection, and contributing to the blood-brain barrier. Their distinctive, star-like morphology is essential to these functions, and abnormalities in astrocyte structure are linked to numerous neurological disorders. However, our understanding of astrocyte morphology, particularly in vivo, remains limited. Traditional imaging methods, such as fluorescence microscopy, introduce challenges like restricting continuous observation and comprehensive morphological analysis. In this study, we present a novel approach utilizing optical diffraction tomography (ODT), an advanced imaging technique that generates 3D refractive index profiles, to image and quantify detailed astrocyte morphology. We demonstrate, for the first time, the application of ODT to image samples through and on disordered glass nanowire (NW) substrates, overcoming the typical challenges posed by nanostructures, which can disrupt phase reconstruction. Crucially, we show that disordered glass nanowire (NW) substrates can induce in vivo-like astrocyte morphology in cultured rat cortical astrocytes. Compared to traditional glass substrates, astrocytes grown on disordered glass NWs substrates exhibited enhanced process branching and greater total arbor length--features typically observed in their natural, in vivo state, a state of advanced maturation. This finding underscores the significant influence of substrate topography on astrocyte structure and highlights the unique potential of nanostructured environments to mimic physiological conditions. By leveraging ODT, we were able to monitor astrocyte behavior on these substrates, providing unprecedented insights into their morphological dynamics. Our study pioneers the use of nanostructured substrates for reconstructing astrocyte morphology and sets the stage for further exploration of how microenvironmental cues shape astrocyte morphology and behavior.

cell biology↗

Bystander base editing interferes with visual function restoration in Leber congenital amaurosis

Base editors (BEs) have emerged as a powerful tool for gene correction with high activity. However, bystander base editing, a byproduct of BEs, presents challenges for precise editing. Here, we investigated the effects of bystander edits on phenotypic restoration in the context of Leber congenital amaurosis (LCA), a hereditary retinal disorder, as a therapeutic model. We observed that in rd12 of LCA model mice, the highest editing activity version of an adenine base editors (ABEs), ABE8e, generated substantial bystander editing, resulting in missense mutations despite RPE65 expression, preventing restoration of visual function. Through AlphaFold-based mutational scanning and molecular dynamics simulations, we identified that the ABE8e-driven L43P mutation disrupts RPE65 structure and function. Our findings underscore the need for more stringent requirements in developing precise BEs for future clinical applications.

genetics↗

Multi-task benchmarking of single-cell multimodal omics integration methods

Single-cell multimodal omics technologies have empowered the profiling of complex biological systems at a resolution and scale that were previously unattainable. These biotechnologies have propelled the fast-paced innovation and development of data integration methods, leading to a critical need for their systematic categorisation, evaluation, and benchmark. Navigating and selecting the most pertinent integration approach poses a significant challenge, contingent upon the tasks relevant to the study goals and the combination of modalities and batches present in the data at hand. Understanding how well each method performs multiple tasks, including dimension reduction, batch correction, cell type classification and clustering, imputation, feature selection, and spatial registration, and at which combinations will help guide this decision. This study develops a much-needed guideline on choosing the most appropriate method for single-cell multimodal omics data analysis through a systematic categorisation and comprehensive benchmarking of current methods. The Stage 1 protocol for this Registered Report was accepted in principle on 30th July 2024. The protocol, as accepted by the journal, can be found at https://springernature.figshare.com/articles/journal_contribution/Multi-task_benchmarking_of_single-cell_multimodal_omics_integration_methods/26789902.

bioinformatics↗

Uncovering Astrocyte Morphological Dynamics Using Optical Diffraction Tomography and Shape-based Trajectory Inference

Astrocytes, integral components of the central nervous system, are increasingly recognized for their multifaceted roles beyond mere support cells. Despite their acknowledged importance, understanding the intricacies of astrocyte morphology and dynamics remains limited. Our study marks the first exploration of astrocytes using optical diffraction tomography (ODT), aiming to establish a solid foundation for their detailed characterization. It offers valuable insights into the morphological changes in postnatal rat cortical astrocytes over a 7-day in vitro period in a label-free manner. Through comprehensive analysis of 3D refractive index maps and shape characterization techniques, we elucidate the developmental trajectory and dynamic morphological transformations of astrocytes in culture. Specifically, our observations revealed increased area and transition to larger, flattened shapes, and alterations in cell volume and density, indicating shifts in cellular composition. Furthermore, by employing unsupervised clustering and pseudotime trajectory analysis, we tracked the morphological evolution of astrocytes from highly directional to evenly spread shapes. These results emphasize the dynamic nature of astrocytes. In addition, this analysis marks the first use of trajectory inference based solely on morphology for neural cell types. Future studies could employ ODT to examine the morphological dynamics and interactions of various neural cell types on other types of substrates.

cell biology↗

The MRE11-RAD50-NBS1 complex both starts and extends DNA end resection in mouse meiosis

Nucleolytic resection of DNA ends is critical for homologous recombination, but its mechanism is not fully understood, particularly in mammalian meiosis. Here we examine roles of the conserved MRN complex (MRE11, RAD50, and NBS1) through genome-wide analysis of meiotic resection in mice with various MRN mutations, including several that cause chromosomal instability in humans. Meiotic DSBs form at elevated levels but remain unresected if Mre11 is conditionally deleted, thus MRN is required for both resection initiation and regulation of DSB numbers. Resection lengths are reduced to varying degrees in MRN hypomorphs or if MRE11 nuclease activity is attenuated in a conditional nuclease-dead Mre11 model. These findings unexpectedly establish that MRN is needed for longer-range extension of resection, not just resection initiation. Finally, resection defects are additively worsened by combining MRN and Exo1 mutations, and mice that are unable to initiate resection or have greatly curtailed resection lengths experience catastrophic spermatogenic failure. Our results elucidate multiple functions of MRN in meiotic recombination, uncover unanticipated relationships between short- and long-range resection, and establish the importance of resection for mammalian meiosis.

genetics↗

Arc controls organ architecture through modulation of Crb and MyoII

Precise orchestration of morphogenetic processes is required to generate organs that are optimally situated within the organism, and that are of the right size and shape to fit and maximize functionality. Here, we describe the role of Arc, a large apical membrane-associated PDZ domain-containing protein, that works through the apical determinant Crumb (Crb) to limit MyoII activity during tissue invagination in the forming Drosophila salivary gland (SG). We show that loss of Arc, attenuation of Crb function, as well as increased activation of non-muscle Myosin II (MyoII) leads to the simultaneous internalization of more precursor cells than normal. Consequently, mature SGs are significantly shorter with more cells surrounding the lumen at all positions along the tube. Correspondingly, overexpression of Arc or SG-specific knockdown of MyoII leads to the formation of longer SGs with fewer cells surrounding the lumen. We show that both Arc PDZ domains are required for Arc function and that they have distinct activities. Finally, we show that Arc facilitates Crb plasma membrane (PM) localization and suggests a model wherein PM-associated Crb stabilizes cellular junctions countering the destabilizing effects of apical medial and junctional pools of activated MyoII, thus limiting the number of primordial cells internalizing at any given time.

developmental biology↗

Loss of p21-activated kinase 4 (PAK4) suppresses pancreatic tumor progression and metastasis through regulating E-cadherin

Pancreatic ductal adenocarcinoma (PDAC) is characterized by a poor prognosis with early and frequent metastasis. While p21-activated kinase 4 (PAK4) has been implicated in cell migration, and invasion, the molecular mechanisms in PDAC remain unknown. In this study, we found that PAK4 overexpression was correlated with poor survival in PDAC patients through analysis of TCGA data. PAK4-amplified PDAC cells showed enhanced mobility in contrast with wild-type. PAK4 knockdown in PAK4 amplified cells inhibited cell migration, invasion, and displacement by increased and stabilized E-cadherin, which was attributed to decreased activity of Cdc42. PAK4 knock-in in PAK4 wild-type models enhanced cell migration, invasion, and displacement by reduced E-cadherin through elevated Cdc42 activity. PAK4 bounded to E-cadherin, Cdc42, and p120ctn in immunoprecipitation. In confocal imaging, the colocalization of PAK4, E-cadherin, p120ctn, and Cdc42 was also identified. In an orthotopic PDAC mouse model, PAK4 knockdown decreased primary tumor size and occurrence of malignant ascites by activation of E-cadherin. Notably, in patients tissue specimens, inverse correlation on expression of PAK4 and E-cadherin were also shown. In conclusion, our study highlights that PAK4 promotes invasive and metastatic behavior by regulating E-cadherin in PDAC. PAK4 could be a potential therapeutic target for PDAC patients. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=120 SRC="FIGDIR/small/594599v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@1755a23org.highwire.dtl.DTLVardef@170b2a1org.highwire.dtl.DTLVardef@1df96edorg.highwire.dtl.DTLVardef@2dc46b_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

Noninvasive time-lapse 3D subcellular analysis of embryo development for machine learning-enabled prediction of blastocyst formation

Accurate embryo quality assessment is central to improving outcomes in in vitro fertilization (IVF), yet current practice relies mainly on subjective two-dimensional (2D) morphology. Here we present a label-free framework for quantitative three-dimensional (3D) embryo phenotyping using low-coherence holotomography (HT). Time-lapse HT enabled volumetric imaging of mouse embryos from the 2-cell stage to the blastocyst without affecting developmental competence, capturing subcellular features at high resolution. Quantitative analysis revealed that matured embryos exhibited higher blastomere counts, greater spatial variability, and tighter nuclear packing, whereas arrested embryos showed enlarged blastomeres, elevated cytoplasmic heterogeneity, and fewer, larger nuclei. Machine learning models trained on these features achieved robust prediction of blastocyst formation (AUC up to 0.958). Together, these findings demonstrate that HT provides objective and interpretable 3D biomarkers that could augment and transform embryo selection in IVF.

developmental biology↗

Impacts of Perinatal Nicotine Exposure on nAChR Expression and Glutamatergic Synaptic Transmission in the Mouse Auditory Brainstem

Exposure to nicotine in utero, often due to maternal smoking, significantly elevates the risk of auditory processing deficits in offspring. This study investigated the effects of chronic nicotine exposure during a critical developmental period on the functional expression of nicotinic acetylcholine receptors (nAChRs), glutamatergic synaptic transmission, and auditory processing in the mouse auditory brainstem. We evaluated the functionality of nAChRs at a central synapse and explored the impact of perinatal nicotine exposure (PNE) on synaptic currents and auditory brainstem responses (ABR) in mice. Our findings revealed developmentally regulated changes in nAChR expression in the medial nucleus of the trapezoid body (MNTB) neurons and presynaptic Calyx of Held terminals. PNE was associated with enhanced acetylcholine-evoked postsynaptic currents and compromised glutamatergic neurotransmission, highlighting the critical role of nAChR activity in the early stages of auditory synaptic development. Additionally, PNE resulted in elevated ABR thresholds and diminished peak amplitudes, suggesting significant impairment in central auditory processing without cochlear dysfunction. This study provides novel insights into the synaptic disturbances that contribute to auditory deficits resulting from chronic prenatal nicotine exposure, underlining potential targets for therapeutic intervention.

neuroscience↗

Neuron-derived Prox1 suppresses injury-induced reprogramming of Muller glia to proliferative retinal progenitor cells

Individuals with retinal degenerative diseases face significant obstacles in restoring normal vision due to the inability to regenerate degenerated retinal cells. While retinal neurons can be regenerated from Muller glia (MG) in cold-blooded vertebrates, this regenerative ability is lacking in mammals, indicating the limited competence of mammalian MG for retinal regeneration. In this study, we elucidate the role of prospero-related homeobox 1 (Prox1) in rendering the mammalian retina incompetent for MG-derived regeneration. Prox1 accumulates in MG in the degenerating human and mouse retinas but not in those in the regenerating zebrafish retina. Strikingly, Prox1 in mouse MG originated from neighboring retinal neurons through intercellular protein transfer. Consequently, inhibition of Prox1 transfer to MG enables the reprogramming of MG into proliferative retinal progenitor cells in injured mouse retinas. Furthermore, we succeeded in regenerating retinal neurons and delaying vision loss in retinitis pigmentosa disease model in mice by adenoassociated viral gene delivery of an anti-Prox1 antibody that sequesters extracellular Prox1 in the mouse retina. Taken together, our findings highlight the therapeutic potential of anti-Prox1 therapy in restoring the regenerative potential of the mammalian retina.

developmental biology↗

Scn2a deletion disrupts oligodendroglia function: Implication for myelination, neural circuitry, and auditory hypersensitivity in ASD

Autism spectrum disorder (ASD) is characterized by a complex etiology, with genetic determinants significantly influencing its manifestation. Among these, the Scn2a gene emerges as a pivotal player, crucially involved in both glial and neuronal functionality. This study elucidates the underexplored roles of Scn2a in oligodendrocytes, and its subsequent impact on myelination and auditory neural processes. The results reveal a nuanced interplay between oligodendrocytes and axons, where Scn2a deletion causes alterations in the intricate process of myelination. This disruption, in turn, instigates changes in axonal properties and neuronal activities at the single cell level. Furthermore, oligodendrocyte-specific Scn2a deletion compromises the integrity of neural circuitry within auditory pathways, leading to auditory hypersensitivity--a common sensory abnormality observed in ASD. Through transcriptional profiling, we identified alterations in the expression of myelin-associated genes, highlighting the cellular consequences engendered by Scn2a deletion. In summary, the findings provide unprecedented insights into the pathway from Scn2a deletion in oligodendrocytes to sensory abnormalities in ASD, underscoring the integral role of Scn2a-mediated myelination in auditory responses. This research thereby provides novel insights into the intricate tapestry of genetic and cellular interactions inherent in ASD.

neuroscience↗

Enhanced mucosal mitochondrial function corrects dysbiosis and OXPHOS metabolism in IBD

BackgroundMitochondrial (Mito) dysfunction in IBD reduces mucosal O2 consumption and increases O2 delivery to the microbiome. Increased enteric O2 promotes blooms of facultative anaerobes (eg. Proteobacteria) and restricts obligate anaerobes (eg. Firmicutes). Dysbiotic metabolites negatively affect host metabolism and immunity. Our novel compound (AuPhos) upregulates intestinal epithelial cell (IEC) mito function, attenuates colitis and corrects dysbiosis in humanized Il10-/- mice. We posit that AuPhos corrects IBD-associated dysbiotic metabolism. MethodsPrimary effect of AuPhos on mucosal Mito respiration and healing process was studied in ex vivo treated human colonic biopsies and piroxicam-accelerated (Px) Il10-/- mice. Secondary effect on microbiome was tested in DSS-colitis WT B6 and germ-free 129.SvEv WT or Il10-/- mice reconstituted with human IBD stool (Hu-Il10-/-). Mice were treated orally with AuPhos (10- or 25- mg/kg; q3d) or vehicle, stool samples collected for fecal lipocalin-2 (f-LCN2) assay and microbiome analyses using 16S rRNA sequencing. AuPhos effect on microbial metabolites was determined using untargeted global metabolomics. AuPhos-induced hypoxia in IECs was assessed by Hypoxyprobe-1 staining in sections from pimonidazole HCl-infused DSS-mice. Effect of AuPhos on enteric oxygenation was assessed by E. coli Nissle 1917 WT (aerobic respiration-proficient) and cytochrome oxidase (cydA) mutant (aerobic respiration-deficient). ResultsMetagenomic (16S) analysis revealed AuPhos reduced relative abundances of Proteobacteria and increased blooms of Firmicutes in uninflamed B6 WT, DSS-colitis, Hu-WT and Hu-Il10-/- mice. AuPhos also increased hypoxyprobe-1 staining in surface IECs suggesting enhanced O2 utilization. AuPhos-induced anaerobiosis was confirmed by a significant increase in cydA mutant compared to WT (O2-utlizing) E.coli. Ex vivo treatment of human biopsies with AuPhos showed significant increase in Mito mass, and complexes I and IV. Further, gene expression analysis of AuPhos-treated biopsies showed increase in stem cell markers (Lgr4, Lgr5, Lrig1), with concomitant decreases in pro-inflammatory markers (IL1{beta},MCP1, RankL). Histological investigation of AuPhos-fed Px-Il10-/- mice showed significantly decreased colitis score in AuPhos-treated Px-Il10-/- mice, with decrease in mRNA of pro-inflammatory cytokines and increase in Mito complexes (ND5, ATP6). AuPhos significantly altered microbial metabolites associated with SCFA synthesis, FAO, TCA cycle, tryptophan and polyamine biosynthesis pathways. AuPhos increased pyruvate, 4-hydroxybutyrate, 2-hydroxyglutarate and succinate, suggesting an upregulation of pyruvate and glutarate pathways of butyrate production. AuPhos reduced IBD-associated primary bile acids (BA) with concomitant increase in secondary BA (SBA). AuPhos treatment significantly decreased acylcarnitines and increased L-carnitine reflective of enhanced FAO. AuPhos increases TCA cycle intermediates and creatine, energy reservoir substrates indicating enhanced OxPHOS. Besides, AuPhos also upregulates tryptophan metabolism, decreases Kynurenine and its derivatives, and increases polyamine biosynthesis pathway (Putresceine and Spermine). ConclusionThese findings indicate that AuPhos-enhanced IEC mitochondrial function reduces enteric O2 delivery, which corrects disease-associated metabolomics by restoring short-chain fatty acids, SBA, AA and IEC energy metabolism. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=110 SRC="FIGDIR/small/584471v1_ufig1.gif" ALT="Figure 1"> View larger version (46K): org.highwire.dtl.DTLVardef@41e437org.highwire.dtl.DTLVardef@1eddf37org.highwire.dtl.DTLVardef@1d9bff3org.highwire.dtl.DTLVardef@c925f0_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

The developing mouse dopaminergic system: Cortical-subcortical shift in D1/D2 receptor balance and increasing regional differentiation

The dopaminergic system of the brain is involved in complex cognitive functioning and undergoes extensive reorganization during development. Yet, these changes are poorly characterized. We have quantified the density of dopamine 1- and 2-receptor (D1 and D2) positive cells across the forebrain of male and female mice at five developmental stages. Our findings show a cortico-subcortical shift in D1/D2 balance, with increasing D1 dominance in cortical regions as a maturational pattern that occurs earlier in females. We describe postnatal trajectories of D1 and D2 cell densities across major brain regions and observe increasing regional differentiation of D1 densities through development. Our results provide the most comprehensive overview of the developing dopaminergic system to date, and an empirical foundation for further experimental and computational investigations of dopaminergic signaling.

neuroscience↗

Comprehensive analysis of CXXX sequence space reveals that S. cerevisiae GGTase-I mainly relies on a2X substrate determinants

Many proteins undergo a post-translational lipid attachment, which increases their hydrophobicity, thus strengthening their membrane association properties or aiding in protein interactions. Geranylgeranyltransferase-I (GGTase-I) is an enzyme involved in a three-step post-translational modification (PTM) pathway that attaches a 20-carbon lipid group called geranylgeranyl at the carboxy-terminal cysteine of proteins ending in a canonical CaaL motif (C - cysteine, a - aliphatic, L - often leucine, but can be phenylalanine, isoleucine, methionine, or valine). Genetic approaches involving two distinct reporters were employed in this study to assess S. cerevisiae GGTase-I specificity, for which limited data exists, towards all 8000 CXXX combinations. Orthogonal biochemical analyses and structure-based alignments were also performed to better understand the features required for optimal target interaction. These approaches indicate that yeast GGTase-I best modifies the Cxa[L/F/I/M/V] sequence that resembles but is not an exact match for the canonical CaaL motif. We also observed that minor modification of non-canonical sequences is possible. A consistent feature associated with well-modified sequences was the presence of a non-polar a2 residue and a hydrophobic terminal residue, which are features recognized by mammalian GGTase-I. These results thus support that mammalian and yeast GGTase-I exhibit considerable shared specificity. Article SummaryThis work investigates yeast GGTase-I specificity through genetics, high throughput sequencing, and two distinct reporter systems. This approach allows for comprehensive evaluation of all CXXX sequence space, which has not been possible with earlier approaches. We identified CXXX sequences supporting geranylgeranylation that differ from the historically defined CaaL sequence often cited in the literature as the GGTase-I target motif, and our results indicate that the last two amino acids of the target motif largely dictate GGTase-I specificity.

genetics↗

Structural insights into CXCR4 modulation and oligomerization

Activation of the chemokine receptor CXCR4 by its chemokine ligand CXCL12 regulates diverse cellular processes. CXCR4 also serves as a key target for diseases such as cancer and HIV. Previously reported crystal structures of CXCR4 bound to antagonists revealed the architecture of an inactive, homodimeric receptor. However, many structural aspects of CXCR4 remain poorly understood, including its activation by CXCL12, as well as its assembly into higher-order oligomers. Here, we use cryoelectron microscopy (cryoEM) to investigate various modes of CXCR4 regulation in the presence and absence of Gi protein. CXCL12 activates CXCR4 by inserting its N-terminus deep into the CXCR4 orthosteric pocket. The binding of FDA-approved antagonist AMD3100 is stabilized by electrostatic interactions with acidic residues in the 7 transmembrane helix bundle. A potent antibody blocker, REGN7663, binds across the extracellular face of CXCR4 and inserts its CDR-H3 loop into the orthosteric pocket. Trimeric and tetrameric structures of CXCR4 reveal, to our knowledge, previously undescribed modes of GPCR oligomerization. Remarkably, CXCR4 adopts distinct subunit conformations in trimeric and tetrameric assemblies, highlighting how oligomerization could allosterically regulate chemokine receptor function.

biochemistry↗

Identification of B cell subsets based on antigen receptor sequences using deep learning

B cell receptors (BCRs) denote antigen specificity, while corresponding cell subsets indicate B cell functionality. Since each B cell uniquely encodes this combination, physical isolation and subsequent processing of individual B cells become indispensable to identify both attributes. However, this approach accompanies high costs and inevitable information loss, hindering high-throughput investigation of B cell populations. Here, we present BCR-SORT, a deep learning model that predicts cell subsets from their corresponding BCR sequences by leveraging B cell activation and maturation signatures encoded within BCR sequences. Subsequently, BCR-SORT is demonstrated to improve reconstruction of BCR phylogenetic trees, and reproduce results consistent with those verified using physical isolation-based methods or prior knowledge. Notably, when applied to BCR sequences from COVID-19 vaccine recipients, it revealed inter-individual heterogeneity of evolutionary trajectories towards Omicron-binding memory B cells. Overall, BCR-SORT offers great potential to improve our understanding of B cell responses.

bioinformatics↗

Divergent opioid-mediated suppression of inhibition between hippocampus and neocortex across species and development

Within the adult rodent hippocampus, opioids suppress inhibitory parvalbumin-expressing interneurons (PV-INs), thus disinhibiting local micro-circuits. However, it is unknown if this disinhibitory motif is conserved in other cortical regions, species, or across development. We observed that PV-IN mediated inhibition is robustly suppressed by opioids in hippocampus proper but not primary neocortex in mice and nonhuman primates, with spontaneous inhibitory tone in resected human tissue also following a consistent dichotomy. This hippocampal disinhibitory motif was established in early development when PV-INs and opioids were found to regulate early population activity. Acute opioid-mediated modulation was partially occluded with morphine pretreatment, with implications for the effects of opioids on hippocampal network activity important for learning and memory. Together, these findings demonstrate that PV-INs exhibit a divergence in opioid sensitivity across brain regions that is remarkably conserved across evolution and highlights the underappreciated role of opioids acting through immature PV-INs in shaping hippocampal development.

neuroscience↗