SOX2-Sensing: Insights into the Role of SOX2 in the Generation of Sensory Cell Types in Vertebrates

Abstract

The SOX2 transcription factor is a key regulator of nervous system development, and its mutation in humans leads to a rare disease characterized by severe eye defects, cognitive defects, hearing defects, abnormalities of the CNS and motor control problems. SOX2 has an essential role in neural stem cell maintenance in specific regions of the brain, and it is one of the master genes required for the generation of induced pluripotent stem cells. Sox2 is expressed in sensory organs, and this review will illustrate how it regulates the differentiation of sensory cell types required for hearing, touching, tasting and smelling in vertebrates and, in particular, in mice.

Keywords: SOX2; hear; sensory; smell; taste; touch; transcription factor.

Figure 1

Sox2 expression during development of sensory organs in mice. (A) Schematic representation of a Merkel cell–neurite complex on the skin. Sox2-expressing Merkel cells are indicated. (B) Schematic representation of the distribution of papillae on the tongue and of the organization of taste buds. Taste receptor cells expressing Sox2 are indicated. Circumvallate papillae (CvPs), foliate papillae (FoPs) and fungiform papillae (FFPs). (C) Schematic representation of inner ear development. Sox2-expressing neurosensory epithelium and support cells (SCs) are indicated. Sox-negative hair cells (HCs) are shown. (D) Schematic representation of the olfactory system. Sox2-expressing sensory epithelium and olfactory epithelium (OE) are indicated. Olfactory sensory neurons (OSNs) projecting to the olfactory bulb (OB) are shown. At the bottom of the figure, a timecourse of mouse development is illustrated.