c. elegans worm

Quality of Synaptic Vesicles

Synaptic vesicles (SVs) store and release neurotransmitters and serve as morphological counterparts of the neurotransmitter quanta. Disruptions in vesicle property create deficits in synaptic transmission that underlie various forms of neurological and psychiatric disorders. Thus, dissecting the key mechanisms (e.g., synaptic vesicle exocytosis and endocytosis) that control the property of neuron communication is important for understanding the activity of the brain in both healthy and disease conditions.

Architecture of synaptic vessicles
Architecture of synaptic vessicles (SVs). (A) A cluster of SVs with homogeneous size. (B) A molecular model of a SV cross-section. High-res version

Neuromodulation and Behavior

Monoamine neurotransmitters and neuropeptides play important roles in modulating the properties of synapses and neurons, which consequently lead to behavior flexibility with changing environmental stimuli. While the importance of neuromodulators is well documented, how environment and past experience shape monoamine and peptide signaling remains largely unknown. Projects in the Bai lab explore these areas by studying the release and the receiving of neuromodulatory signals, and their impacts on animal behavior. 

Diagram of dopamine signaling
Dopamine signaling tunes spatial pattern selectivity in the nematode C. elegans.

Sensory Integration and Plasticity

Multiple neural circuits simultaneously execute distinct functions in the brain. However, these circuits do not work in isolation; rather they interact and influence each other’s performance through reciprocal modulation and plasticity. We are interested in both molecular and circuitry mechanisms that coordinate different brain circuits and govern brain-wide plasticity. For instance, we study cross-modal plasticity that occurs following the loss of a sensory modality. We explore circuit regulation using a novel circuit engineering approach to re-engineer circuit function. 

Diagram depicting sensor integration