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Choe, D. T.

Publications and source records attributed to Choe, D. T..

3 recordsLinked to original sources

Comparative connectomics reveals stage-specific gap junction rewiring that reshapes avoidance behavior

Environmental stress can remodel neural circuits, yet how such rewiring generates behavioral adaptation remains poorly understood. The dauer stage of Caenorhabditis elegans provides a unique model to address this question. Here, we investigated how dauer-specific circuit remodeling alters nociceptive behavior. We found that dauers exhibit markedly shorter avoidance durations than adults. Comparative connectomics revealed substantial expansion of gap junctions within the dauer nociceptive circuit. Calcium imaging further showed that dauer neurons exhibit faster and more transient activity dynamics throughout the circuit. Introducing synthetic dauer-specific gap junctions into adults was sufficient to recapitulate dauer-like neuronal activity patterns and significantly shorten avoidance duration. Despite extensive circuit rewiring, however, avoidance initiation remained preserved across developmental stages. Together, our findings demonstrate that the dauer connectome is selectively rewired through gap junction remodeling to tune behavioral persistence while robustly preserving behavioral initiation, revealing how developmental circuit reorganization balances flexibility and stability for survival under stress.

neuroscience↗

Structural diversity of mitochondria in the neuromuscular system across development

As an animal matures, its neural circuit undergoes alterations, yet the developmental changes in intracellular organelles to facilitate these changes is less understood. Using 3D electron microscopy and deep learning, we developed semi-automated methods for reconstructing mitochondria in C. elegans and collected mitochondria reconstructions from normal reproductive stages and dauer, enabling comparative study on mitochondria structure within the neuromuscular system. We found that various mitochondria structural properties in neurons correlate with synaptic connections and these properties are preserved across development in different neural circuits. To test the necessity of these universal mitochondria properties, we examined the behavior in drp-1 mutants with impaired mitochondria fission and discovered that it caused behavioral deficits. Moreover, we observed that dauer neurons display distinctive mitochondrial features, and mitochondria in dauer muscles exhibit unique reticulum-like structure. We propose that this specialized mitochondria structure may serve as an adaptive mechanism to support stage-specific behavioral and physiological needs.

neuroscience↗

Mind of a dauer: Comparative connectomics reveals developmental plasticity

A fundamental question in neurodevelopmental biology is how flexibly the nervous system changes during development. To address this, we reconstructed the complete connectome of dauer, an alternative developmental stage of nematodes with distinct behavioral characteristics, by volumetric reconstruction and automated synapse detection using deep learning. With the basic architecture of the nervous system preserved, structural changes in neurons, large or small, were closely associated with connectivity changes, which in turn evoked dauer-specific behaviors such as nictation. Graph theoretical analyses revealed significant dauer-specific rewiring of sensory neuron connectivity and increased clustering within motor neurons in the dauer connectome. We suggest that the nervous system in the nematode, probably animals in general, has evolved to respond to harsh environments by reversibly developing a quantitatively and qualitatively differentiated connectome.

neuroscience↗