| First Author | Omura M | Year | 2014 |
| Journal | Mol Cell Neurosci | Volume | 58 |
| Pages | 1-10 | PubMed ID | 24211702 |
| Mgi Jnum | J:203525 | Mgi Id | MGI:5527204 |
| Doi | 10.1016/j.mcn.2013.10.010 | Citation | Omura M, et al. (2014) The beta2-adrenergic receptor as a surrogate odorant receptor in mouse olfactory sensory neurons. Mol Cell Neurosci 58:1-10 |
| abstractText | In the mouse, mature olfactory sensory neurons (OSNs) express one allele of one of the ~1200 odorant receptor (OR) genes, which encode G-protein coupled receptors (GPCRs). Axons of OSNs that express the same OR coalesce into homogeneous glomeruli at conserved positions in the olfactory bulb. ORs are involved in OR gene choice and OSN axonal wiring, but the mechanisms remain poorly understood. One approach is to substitute an OR genetically with another GPCR, and to determine in which aspects this GPCR can serve as a surrogate OR under experimental conditions. Here, we characterize a novel gene-targeted mouse strain in which the mouse beta2-adrenergic receptor (beta2AR) is coexpressed with tauGFP in OSNs that choose the OR locus M71 for expression (beta2AR-->M71-GFP). By crossing these mice with beta2AR-->M71-lacZ gene-targeted mice, we find that differentially tagged beta2AR-->M71 alleles are expressed monoallelically. The OR coding sequence is thus not required for monoallelic expression - the expression of one of the two alleles of a given OR gene in an OSN. We detect strong beta2AR immunoreactivity in dendritic cilia of beta2AR-->M71-GFP OSNs. These OSNs respond to the beta2AR agonist isoproterenol in a dose-dependent manner. Axons of beta2AR-->M71-GFP OSNs coalesce into homogeneous glomeruli, and beta2AR immunoreactivity is detectable within these glomeruli. We do not find evidence for expression of endogenous beta2AR in OSNs of wild-type mice, also not in M71-expressing OSNs, and we do not observe overt differences in the olfactory system of beta2AR and beta1AR knockout mice. Our findings corroborate the experimental value of the beta2AR as a surrogate OR, including for the study of the mechanisms of monoallelic expression. |
