900B Poster - 14. Neural circuits and behavior
Friday April 08, 2:00 PM - 4:00 PM

Authors:
Sydney Shea ¹; Abby Eisold ¹; Lazarina Butkovich ²; Jasper Maniates-Selvin ³; Wei-Chung Lee ³; Matthew Clark ¹; Michael Dickinson ²

Affiliations:
1) Bucknell University, Lewisburg, PA; 2) Caltech, Pasadena, CA; 3) Boston Children's Hospital, Harvard Medical School, MA

Keywords:
l. locomotion/flight; g. neurotransmitters

Muscles provide the force necessary to generate movements that drive locomotor behaviors. Muscles innervated by single motor neurons comprise synergistic motor units that can be recruited to perform a given task. Drosophila use only a dozen pairs of flight steering motor units to regulate wing motion during both quick maneuvers and slow compensatory reflexes. Steering muscles can be functionally grouped according to their size and patterns of activity. Small tonically active muscles allow the fly to steer straight via subtle adjustments in the phase of firing relative to wing strokes. Large phasically active muscles allow the fly to quickly alter heading via rapid changes in muscle activity. Although features of these motor neurons and muscles are relatively well characterized, the neural network of interneurons controlling them is poorly understood. To study the relationship between neural circuitry and flight, we performed an optogenetic screen of Split Gal4 drivers specific to ventral nerve cord interneurons (VNC INs) and recorded changes in stroke amplitude and wingbeat frequency. Results showed that activation of VNC INs had a variety of effects compared to controls, suggesting that dedicated groups govern specific wing motions. Using the MultiColor FlpOut method we have begun matching morphological features of individual behaviorally relevant neurons to those reconstructed via comprehensive connectomic mapping. Future functional studies will determine how these various interneurons alter the activity of specific steering motor units and thus alter wing motion.