Wesley Grueber, PhD

Our lab is interested in patterning and function of the sensory nervous system, with particular focus on proprioceptive and interoceptive systems.

The proprioceptive system endows animals with an ability to sense body position.  This sense is often taken for granted in our daily lives, in that we "intuitively" know where our hands and legs are as we move about, but this information is provided by an array of proprioceptive sensory neurons that are precisely positioned to detect body movements.  This capacity is critically required not only for limbed organisms but also for animals with soft bodies such as Drosophila larvae, which we use as a model to study the functional organization of proprioceptive systems. In recent studies, we exploited the transparent body of Drosophilato simultaneously monitor the activities of a large population body wall proprioceptors using calcium imaging and high-speed volumetric microscopy. Using this approach we identified patterns of sequential activation of proprioceptors during movement that could provide moment-to-moment updates on body position. In further studies we have identified additional proprioceptors in this system that could fill in missing links of body sensing including coordination between different body regions. We have recently begun to explore roles for proprioception in inter-species interactions in diverse model systems.

We are also interested in mechanisms of interoception. The sensing of internal body status is essential for proper functioning of organ systems. In contrast to signals from the classical senses, such as touch, vision, and taste, which have been studied in detail, we are only beginning to understand the sensory circuits that monitor and modulate internal body organs. We study the functions of internal sensory neurons in Drosophilalarvae, focusing on neurons that innervate the respiratory system. We have identified diverse anatomy and chemoreceptor expression in different internal sensory neurons that points to extensive heterogeneity of this system. We propose that this system comprises a major interoceptive system in Drosophila with roles in monitoring diverse internal chemical states, many of which are yet to be explored. Our current studies focus on identifying the roles for interoceptors in physiological homeostasis, from the molecular to behavioral levels.