CAREER: Transcriptional Regulation of Piezo2 Channels in a Behavioral and Evolutionary Context

Currently, Piezo2 is the only verified mechanically-gated ion channel known to transduce touch in vertebrate somatosensory neurons. Touch is also important in an organismal/evolutionary context, however, how Piezo2 is transcriptionally regulated (i.e., how it gets expressed in the cells that need to sense force) is completely unknown. Thus, there is a critical need to determine how Piezo2 is regulated both on developmental and evolutionary timescales. To do this we will leverage a novel clade of model organisms: Ducks (Anatidae). Many species of duck are expert “tactile foragers,” using the sense of touch in their bill which is innervated by trigeminal ganglia (TG) neurons to feed. Dependence on tactile foraging methods varies widely across species. The percentage of Piezo2 positive neurons expressed in duck TG varies widely in species with differing foraging behavior, suggesting Piezo2 is differentially regulated across species (1). In specific objective 1, we will identify regulatory elements for Piezo2 using multiomics in TG neurons at developmental timepoints spanning the onset of Piezo2 expression and experimentally validate promoters/enhancer identified using in ovo electroporation of reporter constructs. In objective 2, we will characterize a second axis of Piezo2 regulation—it’s role in the evolution of sensory specialization by correlating Piezo2 expression, functional mechanosensitivity, and variation in regulatory elements in duck species with disparate mechanosensory abilities. Finally, in teaching/research objective 3, we will use Course-Based Undergraduate Research (CURE) courses to refine and extend our novel behavioral assays for quantifying tactile discrimination ability in ducks, with the immediate goal of determining the extent of behavioral species diversity in tactile foraging, and long-term goal of testing manipulations of Piezo2.