Mouse Cyp2g1 gene: Promoter structure and tissue-specific expression of a Cyp2g1-LacZ fusion gene in transgenic mice

The structure of the mouse Cyp2g1 gene was determined to identify regulator y regions important for its olfactory mucosa-specific expression. Two Cyp2g 1 genomic clones were isolated and characterized. A 3.6-kilobase 5'-flankin g sequence was used to prepare a Cyp2g1-LacZ fusion gene for transgenic mic e production. Transgene expression, as determined by beta -galactosidase ac tivity in tissue extracts, was detected in the olfactory mucosa, but not in any other tissues examined, in five different transgenic lines. Thus, the 3,6-kilobase fragment contained regulatory elements sufficient for olfactor y mucosa-specific and proper developmental expression of the reporter gene. However, histological and immunohistochemical studies indicated that the e xpression of the transgene in the olfactory mucosa was patchy and the cellu lar expression patterns of the transgene did not exactly match that of the endogenous gene. These results implicate the presence of additional regulat ory sequences that are necessary for the correct cell type-selectivity with in the olfactory mucosa, (C) 2001 Academic Press.