Skin, muscle, joints, and internal organs encapsulate specialized sensory neurons that detect mechanical cues in the form of touch and movement. The ability to perform most, if not all of the essential activities of daily living depends on information from these somatosensory, proprioceptive, and visceral sensory neurons. Thus, a better understanding of their function and sensitivity to mechanical and chemical stress is of vital importance for health. This research program focuses on the skin-neuron composite tissues responsible for touch and seeks to decipher how mechanical force is translated from the skin surface to embedded sensory neurons and converted into electrical signals that give rise to tactile perceptions. The work combines genetic dissection in a simple invertebrate (C. elegans nematodes) with electron microscopy, high-performance tools (self-sensing cantilevers) for delivering mechanical stimuli under feedback control and for optically monitoring tissue deformation and neuronal activation with electrophysiology and calcium imaging. The research team includes biologists, engineers and physicists and integrates experimental work with theory and simulation. In addition to seeking a comprehensive understanding of mechanosensation by skin-neuron composites, the research program will also address the outstanding question of how neurons bend without breaking. Based on preliminary work, we also plan to leverage our knowledge of touch sensation and its molecular basis to investigate how chemical stressors linked to diabetes (glucose) and chemotherapy (paclitaxel) affect the function and morphology of skin-neuron composites. The knowledge we seek to acquire is relevant to all animals, including humans that rely on skin-neuron composites for touch sensation.

Public Health Relevance

Peripheral and autonomic neuropathies degrade quality of life and are linked to autoimmune disease and prevalent in patients receiving chemotherapy, but few treatments exist to alleviate these conditions. Because our skin and internal organs are in constant motion, so are the sensory neurons embedded in these tissues. The proposed multidisciplinary experiments and integrated theoretical research exploits a simple genetic model to develop a comprehensive understanding of how mechanical force is detected by sensory neurons and how these same neurons bend without breaking, focusing on cytoskeletal structures like microtubules and spectrin that are conserved in humans and implicated in sensitivity to traumatic brain injury.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Unknown (R35)
Project #
1R35NS105092-01
Application #
9458387
Study Section
Special Emphasis Panel (ZNS1)
Program Officer
Gnadt, James W
Project Start
2017-12-15
Project End
2025-11-30
Budget Start
2017-12-15
Budget End
2018-11-30
Support Year
1
Fiscal Year
2018
Total Cost
Indirect Cost
Name
Stanford University
Department
Biophysics
Type
Schools of Medicine
DUNS #
009214214
City
Stanford
State
CA
Country
United States
Zip Code
94304
Mazzochette, E A; Nekimken, A L; Loizeau, F et al. (2018) The tactile receptive fields of freely moving Caenorhabditis elegans nematodes. Integr Biol (Camb) 10:450-463
Kubanek, Jan; Shukla, Poojan; Das, Alakananda et al. (2018) Ultrasound Elicits Behavioral Responses through Mechanical Effects on Neurons and Ion Channels in a Simple Nervous System. J Neurosci 38:3081-3091