The ability to sense the world though physical contact is essential for all living organisms. The sense of touch is essential for navigation in the environment, object recognition, detection of pain and pleasure. It facilitates the establishment of maternal bonds and underlies the development of social behaviors. The sense of touch includes the sense of physical contact and temperature, but the mechanism is poorly understood. This project seeks to reveal molecular principles underlying the detection of physical touch, and understand how temperature influences this process. These studies will use tactile foraging ducks that allow examination of these general physiological problems through the perspective of a tactile specialist animal. This research will provide mechanistic insights into the process of touch detection and reveal general principles of mechanosensitivity in vertebrates. The broader impact activities aim to promote science among school students, with a focus on ethnic and socioeconomic groups underrepresented among scientists. The PI will reach out to schools in CT, MA and NY to teach how people feel touch, warmth and cold, how they see, smell or taste. Most of the trainees are female, underrepresented minorities, economically disadvantaged, or from families without prior college graduates. The activities are designed and implemented by undergraduates, PhD students and postdocs from the lab, under close supervision of the principal investigator. This approach provides a unique teaching experience to our lab members and help them advance professionally to become educator-researchers.
In many vertebrates, fine tactile tasks are accomplished by organs covered with glabrous skin, such as the palm of hand in primates, or the bill of tactile foraging ducks. These organs specialize in the detection of the lightest forms of touch, such as transient contact and vibration, via mechanosensory corpuscles. How corpuscles convert touch into electrical signaling, what molecules are involved and how they work, remains largely unknown. The investigators will approach this problem by studying mechanosensitivity in the bill of tactile specialist ducks. They showed that duck bill contains numerous lamellar corpuscles innervated by trigeminal mechanoreceptors. Here, the investigator proposes to use the duck model to reveal general principles of touch detection by neuronal and non-neuronal components of mechanosensory corpuscles. This project aims to: (1) Determine the molecular basis of tactile-thermal interaction in neuronal mechanoreceptors. Mild cooling potentiates tactile acuity in vertebrates, but the mechanism is unknown. This project will test the hypothesis that cooling increases the ability of neuronal mechanoreceptors to convert touch into excitation, and identify the molecular basis of this process. (2) Investigate whether lamellar cells from Herbst (Pacinian) corpuscles can detect touch. It is well established that lamellar cells form a cushion around the neuronal core, acting as a passive mechanical filter. The investigator aims to test the hypothesis that lamellar cells are also mechanically sensitive, and are able to convert touch into excitation, actively contributing to the detection of touch.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.