Genomic organization and chromosomal localization of the mouse Connexin36 (mCx36) gene

Connexin36 (Cx36) is a new connexin that was recently cloned in mouse, rat and human. It is highly expressed in neurons of the CNS. To gain insight into the transcriptional regulation of this gene, we have cloned the genomic region containing the entire mCx36 gene and sequenced about 7.6kb around the coding region. The computer analysis of this sequence was helpful in defining putative regulative sequences. Using both 5'-RACE and RNAse protection assay, we have mapped the transcription starting site commonly used in both adult olfactory bulb and brain, in position -479 from the ATG. By 3'-RACE, we defined the polyadenylation site used that is located 1436nt downstream the stop codon. The expected transcript is 2875nt long and is consistent with the 2.9kb transcript found in the same tissues by Northern blot. Finally, we have mapped mCx36 on chromosome 2 in the position F3 in a region that is synthenic to human chromosome 15q14, where the human Cx36 gene has been recently mapped.