Phox2b-Cre BAC transgenic mice are viable and fertile, with Cre recombinase expression under control of the Phox2b promoter/enhancer regions within the BAC transgene. cre-expressing neurons co-express PHOX2B (as shown by in situ hybridization). Phox2b-Cre BAC transgenic mice from founder line 3 exhibit cre expression directed primarily to the hindbrain; specifically the dorsal motor nucleus of the vagus (DMV) in parasympathetic visceral and branchial motor neurons, nodose sensory ganglia, and nucleus of the solitary tract (NTS) cells. No transgene expression is reported in hypothalamus or spinal cord. Although endogenous Phox2b expression is reported in peripheral ganglia along with the enteric nervous system, no peripheral transgene expression is reported for these Phox2b-Cre BAC transgenic mice. When bred with mice containing a loxP-flanked sequence of interest, Cre-mediated recombination will result in deletion of the floxed sequences in the offspring. These Phox2b-Cre BAC transgenic mice may be used to generate conditional mutations for studying neuronal cell types expressing/depending on the Phox2b transcription factor for energy balance, glucose homeostasis, and autonomic breathing/respiration. Specifically, these mice may be useful for studying human respiratory disease, central chemoreceptive neurons in the retrotrapezoid nucleus, respiratory rhythmogenesis, and autonomic nervous system dysregulation (such as congenital central hypoventilation syndrome (CCHS) or Ondine-Hirschsprung disease).
For example, when Phox2b-Cre BAC transgenic mice are bred with floxed leptin receptor mice (Stock No. 008327), the resulting offspring allow studying hindbrain nucleus of the solitary tract (NTS) leptin receptor function in NTS appetite, hunger, and food consumption.
