Related Experiment Video
Updated: Jun 30, 2025

The Olfactory System as a Model to Study Axonal Growth Patterns and Morphology In Vivo
Published on: October 30, 2014
Illuminating the terminal nerve: Uncovering the link between GnRH-1 neuron and olfactory development
Enrico Amato1, Ed Zandro M Taroc1, Paolo E Forni1
1Department of Biological Sciences, The Center for Neuroscience Research, The RNA Institute, University at Albany, State University of New York, Albany, New York, USA.
Abstract:
During embryonic development, the olfactory placode (OP) generates migratory neurons, including olfactory pioneer neurons, cells of the terminal nerve (TN), gonadotropin-releasing hormone-1 (GnRH-1) neurons, and other uncharacterized neurons. Pioneer neurons from the OP induce olfactory bulb (OB) morphogenesis. In mice, GnRH-1 neurons appear in the olfactory system around mid-gestation and migrate via the TN axons to different brain regions. The GnRH-1 neurons are crucial in controlling the hypothalamic-pituitary-gonadal axis. Kallmann syndrome is characterized by impaired olfactory system development, defective OBs, secretion of GnRH-1, and infertility. The precise mechanistic link between the olfactory system and GnRH-1 development remains unclear. Studies in humans and mice highlight the importance of the prokineticin-2/prokineticin-receptor-2 (Prokr2) signaling pathway in OB morphogenesis and GnRH-1 neuronal migration. Prokr2 loss-of-function mutations can cause Kallmann syndrome (KS), and hence the Prokr2 signaling pathway represents a unique model to decipher the olfactory/GnRH-1 connection. We discovered that Prokr2 is expressed in the TN neurons during the critical period of GnRH-1 neuron formation, migration, and induction of OB morphogenesis. Single-cell RNA sequencing identified that the TN is formed by neurons distinct from the olfactory neurons. The TN neurons express multiple genes associated with KS. Our study suggests that the aberrant development of pioneer/TN neurons might cause the KS spectrum.
More Related Videos
11:08Recording Temperature-induced Neuronal Activity through Monitoring Calcium Changes in the Olfactory Bulb of Xenopus laevis
Published on: June 3, 2016
10:11In-depth Physiological Analysis of Defined Cell Populations in Acute Tissue Slices of the Mouse Vomeronasal Organ
Published on: September 10, 2016
Related Concept Videos
Physiology of Smell and Olfactory Pathway
The olfactory...
Olfactory Receptors: Location and Structure
Olfaction
The olfactory receptors are embedded in the cilia of the...
G-Protein Gated Ion Channels
Sensory...
Cranial Nerves: Types Part I
Olfactory Nerve (Cranial Nerve I)
The olfactory nerve, or cranial nerve I, is unique as it is purely sensory and dedicated to the sense of smell. This nerve originates in the olfactory epithelium of the...
The Physiology of Taste