Biology subjects

Lin, D.-T.

Publications and source records attributed to Lin, D.-T..

6 recordsLinked to original sources

bioRxiv2025

Broad brain biodistribution conferred by an AAV to restore TDP-43 function mitigates Frontotemporal Demenia-like deficits

TDP-43 dysfunction is an early pathogenic determinant of frontotemporal lobar degeneration with TDP-43 pathology (FTLD-TDP), a devastating disorder currently without effective therapy. Here, we exploit a blood-brain-barrier (BBB)-permeable AAV (AAV-PHP.eB) that confers broad brain biodistribution to restore TDP-43 function in a TDP-43 deficient model (CamKIIa-CreER;Tardbp mice) that mimics the early stage of TDP-43 dysfunction occurring in FTLD-TDP. Intracerebroventricular delivery by AAV-PHP.eB of CTR, our previously characterized splicing repressor, revealed its accumulation in [~]40% of adult hippocampal neurons. Remarkably, treatment of adult CamKIIa-CreER;Tardbpf/fmice with AAV-PHP.eB-CTR restored TDP-43 function, attenuated neuronal aberrant activity and memory deficits, and rescued neuron loss. Importantly, we showed that TDP-43s autoregulatory element restricts CTR expression to a physiological range. No overt phenotype was observed after long-term exposure to AAV-PHP.eB-CTR in aged mice, highlighting a favorable safety profile for this gene therapy. These results validate that BBB-crossing AAVs can deliver CTR with a biodistribution in the adult brain that is broad enough to rescue FTD-like phenotypes, supporting clinical testing of this gene therapy for FTLD-TDP.

neuroscience↗

bioRxiv2025

Patchy Striatonigral Neurons Modulate Locomotor Vigor in Response to Environmental Valence

Spiny projection neurons (SPNs) in the dorsal striatum play crucial roles in locomotion control and value-based decision-making. SPNs, which include both direct-pathway striatonigral and indirect-pathway striatopallidal neurons, can be further classified into subtypes based on distinct transcriptomic profiles and cell body distribution patterns. However, how these SPN subtypes regulate spontaneous locomotion in the context of environmental valence remains unclear. Using Sepw1-Cre transgenic mice, which label a specific SPN subtype characterized by a patchy distribution of cell bodies in the dorsal striatum, we found that these patchy striatonigral neurons constrain motor vigor in response to valence differentials. In a modified light/dark box test, mice exhibited differential walking speeds between the light and dark zones. Genetic ablation of these patchy SPNs disrupted restful slowing in the dark zone and increased zone discrimination by speed. In vivo recordings linked the activity of these neurons to zone occupancy, speed, and deceleration, with a specific role in mediating deceleration. Furthermore, chemogenetic activation of patchy SPNs--and optical activation of striatonigral neurons in particular--reduced locomotion and attenuated speed-based zone discrimination. These findings reveal that a subtype of patchy striatonigral neurons regulates implicit walking speed selection based on innate valence differentials.

neuroscience↗

bioRxiv2025

Distinct prelimbic cortex ensembles encode response execution and inhibition

Learning when to initiate or withhold actions is essential for survival and requires integration of past experiences with new information to adapt to changing environments. While stable prelimbic cortex (PL) ensembles have been identified during reward learning, it remains unclear how they adapt when contingencies shift. Does the same ensemble adjust its activity to support behavioral suppression upon reward omission, or is a distinct ensemble recruited for this new learning? We used single-cell calcium imaging to longitudinally track PL neurons in rats across operant food reward Training, Extinction and Reinstatement, trained rat-specific decoders to predict trial-wise behavior, and implemented an in-silico deletion approach to characterize ensemble contributions to behavior. We show that operant training and extinction recruit distinct PL ensembles that encode response execution and inhibition, and that both ensembles are re-engaged and maintain their roles during Reinstatement. These findings highlight ensemble-based encoding of multiple learned associations within a region, with selective ensemble recruitment supporting behavioral flexibility under changing contingencies.

neuroscience↗

bioRxiv2022

Striosomes constrain locomotor vigor with respect to an innate valence differential

Survival demands that safe and unsafe contexts are met with different locomotor profiles, yet whether striatal microcircuitry links contextual valence to spontaneous locomotor vigor is unresolved. Here we test for striosome contributions to spontaneous locomotion using ablation, calcium imaging and chemogenetics in the context of a modified Light/Dark box test. We found that locomotor speed reflects the unlearned, external valence differential present in this test, and that striosomes gate valence-oriented speed selection. Our data suggest that striosomes dampen motor vigor associated with lesser valence, or elevated anxiety. HighlightsO_LIMice explore the light and dark zones in Light/Dark box with different walk speed C_LIO_LIStriosome ablation reduces restful slowing and elevates speed relative to zone C_LIO_LIMany striosome neurons exhibit light-zone preference and speed related activity C_LIO_LIStriosome enhancement slows mice and blunts zone discrimination by speed C_LI

neuroscience↗

bioRxiv2021

Distinct Hippocampal Neuronal Reactions Reveal Different Neuronal Codes for Memory Generalization

To survive in an ever-changing world we need to learn and memorize associations of environmental stimuli and generalize them to new situations. Both memory and generalization critically rely on the hippocampus, but it is unclear how hippocampal neuronal activities represent memory and generalization, and if a conserved hippocampal mechanism serves these functions. Here we compared neuronal activities in hippocampal CA1 region of two sub-strains of the widely used C57BL/6 mice, C57BL/6J (B6J) and C57BL/6NCrl (B6NCrl), in contextual fear conditioning. Both sub-strains learnt well but differed in freezing and generalization. They displayed distinct early-late bi-phasic reactions to the unconditioned stimulus. While in both sub-strains the neurons showing late-phase reactions were preferentially engaged in memory representation, the neuronal activity feature that correlated with generalization level differed in the two sub-strains: in B6NCrl, these neurons activity level during learning negatively correlated with the generalization level; in B6J, functional coupling of these late-phase neurons with other neurons positively correlated with the generalization level. We further found that the distinct neuronal reactions were accompanied by distinct GABAb receptor-mediated inhibition but not by differences in the major synaptic inputs or neuronal excitability of the CA1. Therefore, this comparative study reveals two signature neuronal activity features in learning that can predict generalization levels. The results also demonstrate that differences in hippocampal network properties lead to diverse hippocampal mechanisms in memory encoding and generalization.

neuroscience↗

bioRxiv2021

Stratum Lacunosum-moleculare Interneurons of the Hippocampus Coordinate Memory Encoding and Retrieval

Encoding and retrieval of memory are two processes serving distinct biological purposes but operating in highly overlapping brain circuits. It is unclear how the two processes are coordinated in the same brain regions, especially in the hippocampal CA1 region where the two processes converge at the cellular level. Here we find that the neuron-derived neurotrophic factor (NDNF)-positive interneurons at stratum lacunosum-moleculare (SLM) in CA1 play opposite roles in memory encoding and retrieval. These interneurons show high activities in learning and low activities in recall. Increasing their activity facilitates learning but impairs recall. They inhibit the entorhinal- but dis-inhibit the CA3- inputs to CA1 pyramidal cells and thereby either suppress or elevate CA1 pyramidal cells activity depending on animals behavioral states. Thus, by coordinating entorhinal- and CA3- dual inputs to CA1, these SLM interneurons are key to switching the hippocampus between encoding and retrieval modes.

neuroscience↗