Poster abstracts
Poster number 70 submitted by Lindsay Anderson
Uncovering how serotonergic pathway in the dorsal raphe nucleus modulates thermal preference in larval zebrafishng how serotonergic pathway in the dorsal raphe nucleus modulates thermal preference in larval zebrafish
Lindsay Anderson (1Department of Neuroscience, The Ohio State University College of Medicine, Columbus, OH, USA 2Neuroscience Graduate Program, The Ohio State University, Columbus, OH, USA), Martin Haesemeyer (1Department of Neuroscience, The Ohio State University College of Medicine, Columbus, OH, USA), Parv Sharma (The Ohio State University)
Abstract:
The serotonergic system is an important regulator of temperature homeostasis. Disruption within the serotonergic pathway leads to impaired body temperature regulation and inappropriate physiological responses to thermal stress, which can be recovered by selective serotonin reuptake inhibitors. Preferred body temperature is flexible, however, identifying how serotonergic signaling effects thermal preference and behavioral modulation is challenging at the circuit level. To investigate the underlying thermoregulatory mechanisms of the serotonergic system, we will leverage the larval zebrafish model. Larval zebrafish 1) possess a highly conserved serotonergic system, 2) have a transparent brain during the larval stage, providing access to large-scale visualization of neuronal activity, and 3) display a stereotyped behavioral repertoire that can be readily quantified. Recently, we identified a crucial relay of the behavioral thermoregulatory circuit in the zebrafish medulla, which encodes temperature. In zebrafish, the nucleus of the medial longitudinal fasciculus (nMLF) is critical for generating motor commands. Our preliminary behavioral data indicate that selective functional cell ablation of the nMLF reduces time spent in preferred temperature and alters swim distance from adverse temperatures. Furthermore, serotonergic neurons within the dorsal raphe nucleus (DRN) project to the nMLF and may preferentially modulate excitatory neurons. This link between the DRN and the nMLF may be critical for tuning thermoregulatory behaviors by refining motor output. We will test how serotonin effects temperature encoding in the medulla, by combining functional calcium imaging, 2-photon cell ablation, and computational modeling to uncover the contributions of individual temperature responsive neuronal subtypes in sensory processing. Furthermore, we will assay thermoregulatory behavioral strategies after cell ablation in the nMLF to uncover how the DRN-nMLF pathway interacts to relay motor information about the thermal environment. This work will advance our understanding of how neural circuits anticipate environmental changes and drive adaptive behaviors, providing a model for sensorimotor integration.
Keywords: thermoregulation, neural circuits, feedback