The inner ear consists of the
cochlea, dedicated to hearing and the vestibular organs, dedicated to balance
functions, including gaze stabilization, postural control and spatial
navigation. These two systems share the same developmental origin and mechanosensitive
hair cells are used by both but to achieve distinct functions. Comparing to
other sensory systems (e.g. visual, somatosensory), the molecular heterogeneity
of neurons in the inner ear and how they contribute to the morphological,
physiological and functional diversity have not been well-established and
appreciated. I demonstrated, during my postdoc, that type I SGNs consist of
three molecularly distinct subtypes (named type Ia, type Ib and type Ic), which
exhibit anatomical and physiological differences. Specification of the subtypes
is finished postnatally in an activity dependent manner. These results can provide
new angles for the mechanistic understanding of sensory coding in the auditory
system.
The
vestibular system is critical to our sense of balance and spatial orientation.
Malfunctions of the system lead to balance disorders that can affect 15 percent
of the adult population, especially the elderly. Comparing to other sensory
systems, such as the auditory system, this second part of the inner ear has
drawn less public or scientific attention. Vestibular ganglion neurons (VGNs)
innervate five distinctive end organs to carry out diverse functions ranging
from gaze stabilization and spatial navigation to cognitive functions and
autonomic regulations. Accordingly, VGNs exhibit pronounced anatomical and
physiological diversity. We plan to begin the characterization of the
vestibular circuitries with the molecular and cellular diversity of the
vestibular ganglion neurons.
Publications
1. Sun S, Siebald C, Mueller U. (2021) Subtype Maturation of Spiral Ganglion Neurons. Current Opinion in Otolaryngology &
Head and Neck Surgery 29(5):391-399.
2. Sun S*, Babola T*, Palermo A*, So K, Nguyen M, Su S,
Palermo A, Bergles D, Burns J, Mueller U. (2018) Hair Cell Mechanotransduction
Regulates Spontaneous Activity and Spiral Ganglion Subtype Specification in the
Auditory System. Cell 174(5):1246-1632. *contributed equally
to this work.
Highlighted/previewed in:
Whalley, Nature Review Neuroscience.
19,579 (2018)
Kandler, Neuron. 2018.07.043
Fekete, F1000.
3. Sun S*, Xu Q*, Guo C, Guan Y,
Liu Q and Dong X. (2017) Leaky gate model: intensity-dependent coding of pain
and itch in the spinal cord. Neuron, 93(4):840-853. *contributed equally
to this work.
Highlighted/previewed in:
Pereira and Lerner, Neuron. 2017.02.016
4. Sun S, Dong X. (2016) Trp channels and itch. Seminars in immunopathology 38(3), 293-307.
5. Reddy
VB*, Sun S*, Azimi E, Elmariah SB,
Dong X, Lerner EA. (2015) Redefining the concept of protease-activated
receptors: cathepsin S evokes itch via activation of Mrgprs. Nature communications, 6:7864. *contributed equally to this work.
6. Li Z, Tseng P.-Y, Tiwari
V, Xu Q, He S.-Q, Wang Y, Zheng Q, Han L, Wu Z, Blobaum A.L, Cui Y, Tiwari V, Sun
S, Cheng Y, Huang-Lionnet J.H.Y, Geng Y, Xiao B, Peng J, Hopkins C, Raja
S.N, Guan Y, Dong X. (2017) Targeting human Mas-related G protein-coupled
receptor X1 to inhibit persistent pain. Proc. Natl. Acad. Sci, 114(10): E1996-2005.
7. Kim YS, Chu Y, Han L, Li M, Li Z, Lavinka PC, Sun S, Tang Z, Park K, Caterina MJ, Ren
K, Dubner R, Wei F, Dong X. (2014) Central terminal sensitization of TRPV1 by
descending serotonergic facilitation modulates chronic pain. Neuron, 81(4):873-87.
8. Liu Q, Sikand P, Ma C, Tang Z, Han L, Li Z, Sun S, LaMotte RH, Dong X. (2012)
Mechanisms of itch evoked by β-alanine. J
Neurosci.3509-12.
Invited Book Chapters
Itch and Pain: Similarities,
Interactions and Differences
Chapter: Interneurons and Their Roles
in Itch and Pain, Author: Shuohao Sun
International Association for the Study
of Pain Press (2020年7月)