PT  - JOURNAL ARTICLE
AU  - Wayne I. L. Davies
AU  - Soufien Sghari
AU  - Brian A. Upton
AU  - Christoffer Nord
AU  - Max Hahn
AU  - Ulf Ahlgren
AU  - Richard A. Lang
AU  - Lena Gunhaga
TI  - Distinct Opsin 3 (<em>Opn3</em>) Expression in the Developing Nervous System during Mammalian Embryogenesis
AID  - 10.1523/ENEURO.0141-21.2021
DP  - 2021 Sep 01
TA  - eneuro
PG  - ENEURO.0141-21.2021
VI  - 8
IP  - 5
4099  - http://www.eneuro.org/content/8/5/ENEURO.0141-21.2021.short
4100  - http://www.eneuro.org/content/8/5/ENEURO.0141-21.2021.full
SO  - eNeuro2021 Sep 01; 8
AB  - Opsin 3 (Opn3) is highly expressed in the adult brain, however, information for spatial and temporal expression patterns during embryogenesis is significantly lacking. Here, an Opn3-eGFP reporter mouse line was used to monitor cell body expression and axonal projections during embryonic and early postnatal to adult stages. By applying 2D and 3D fluorescence imaging techniques, we have identified the onset of Opn3 expression, which predominantly occurred during embryonic stages, in various structures during brain/head development. In addition, this study defines over twenty Opn3-eGFP-positive neural structures never reported before. Opn3-eGFP was first observed at E9.5 in neural regions, including the ganglia that will ultimately form the trigeminal, facial and vestibulocochlear cranial nerves (CNs). As development proceeds, expanded Opn3-eGFP expression coincided with the formation and maturation of critical components of the central and peripheral nervous systems (CNS, PNS), including various motor-sensory tracts, such as the dorsal column-medial lemniscus (DCML) sensory tract, and olfactory, acoustic, and optic tracts. The widespread, yet distinct, detection of Opn3-eGFP already at early embryonic stages suggests that Opn3 might play important functional roles in the developing brain and spinal cord to regulate multiple motor and sensory circuitry systems, including proprioception, nociception, ocular movement, and olfaction, as well as memory, mood, and emotion. This study presents a crucial blueprint from which to investigate autonomic and cognitive opsin-dependent neural development and resultant behaviors under physiological and pathophysiological conditions.