Catherine G. Dulac
Board Member: 2013 - 2015
Molecular and Developmental Biology of Sensory Systems
Sensory stimuli are detected by specialized receptors in sensory organs and the signals hence generated flow through multiple and interconnected centers of the brain where they are analyzed and processed into complex sensory perception. Processing of the sensory information requires the coding of sensory inputs into specific patterns of neuronal activity.
Our group is exploring the molecular logic of olfactory signaling underlying the coding of odorant- and pheromone-mediated signals and is interested in the developmental processes that ensure appropriate neuronal connections between the olfactory sensory neurons and the brain.
In mammals, olfactory sensory perception is mediated by two anatomically and functionally distinct sensory organs: the main olfactory epithelium (MOE) and the vomeronasal organ (VNO). Pheromones activate the vomeronasal organ (VNO) in order to provide information about gender, dominance and reproductive status of the animal and elicit innate social and sexual behaviors along with dramatic neuroendocrine responses.
We have developed a molecular technology which enabled us to construct and screen cDNA libraries prepared from single neurons. The differential screen of single cell cDNA libraries prepared from two isolated VNO neurons had led to the isolation of two independent families of genes which are likely to encode mammalian pheromone receptors. Patterns of receptor gene expression suggest that the VNO is organized into discrete and sexually dimorphic functional units that may permit segregation of pheromone signals leading to specific arrays of behaviors and neuroendocrine responses.
The isolation of these genes from the VNO should provide new insights into the chemical nature of the pheromones themselves, the molecular mechanisms by which pheromone perception leads to innate and stereotyped behaviors and the molecular mechanisms directing the development of the olfactory and vomeronasal systems.