| Abstract: |
Our previous studies has identified and characterized fourteen splice variants of the mouse mu-opioid receptor (MOR-1) gene. Here we report isolation of an additional mouse MOR-1 splice variant, mMOR-1R, using an RT-PCR strategy. Sequence analysis indicates that mMOR-1R contains another new exon, exon 15, with an exon composition of 1, 2, 3 and 15. Exon 15 has been mapped to downstream of the exon 3 with similar location as the fourth exon of hMOR-1R. Exon 15 is predicted to encode 70 amino acids in the C-terminal of the mMOR-1R, which contains putative phosphorylation sites for both cAMP-and cGMP-dependent protein kinase and protein kinase C. Northern blot analysis of mouse brain total RNA using an exon 15 probe showed a distinct band, approximately 1.8 kb. Expression of the mMOR-1R in mouse brain was also determined by Western blot analysis with a specific mMOR-1R antibody. Pharmacological studies in CHO cells stably transfected with the mMOR-1R cDNA suggested that mMOR-1R encodes a mu-opioid receptor. |
