RT Journal Article
SR Electronic
T1 Molecular Organization of the Olfactory Septal Organ
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 8383
OP 8390
DO 10.1523/JNEUROSCI.2222-04.2004
VO 24
IS 38
A1 Tian, Huikai
A1 Ma, Minghong
YR 2004
UL http://www.jneurosci.org/content/24/38/8383.abstract
AB The septal organ in the mammalian nose is a distinct chemosensory organ sitting in the air path. To gain insights into its organization and function, we analyzed the chemoreceptors expressed in this area. By combining cDNA cloning, Affymetrix (Santa Clara, CA) genechips covering all the mouse olfactory receptor genes, and in situ hybridization, we achieved a relatively complete expression profile of the olfactory receptor genes in the septal organ. The majority of the septal neurons express only a few receptor genes in varying patterns, with the top one in ∼50% of the cells and the top eight together in ∼93% of the cells. We demonstrated that a single neuron expresses only one receptor by a thorough combination of all the major septal receptor genes in double-labeling studies. These septal receptor genes do not form a single subfamily. Instead, these genes are distributed on a few major branches of the phylogenetic tree covering all the mouse olfactory receptors. Most of these genes are also concentrated in certain areas within the most ventral zone of the main olfactory epithelium, although their expression patterns do not match those in the septal organ. In contrary to the previous view of random distribution, our results indicate that certain olfactory receptors form “hot spots” in the nose.