The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 
 
 
 
 

Production of rat soluble and membrane-bound catechol O-methyltransferase forms from bifunctional mRNAs.

In the rat, the catechol O-methyltransferase (COMT) gene has been found to contain two promoters, P1 and P2. This organization enables the gene to produce a soluble (S-COMT) and a membrane-associated (MB-COMT) protein by using two in-frame ATG initiation codons (S- and MB-ATG). The P1 promoter expresses a 1.6 kb transcript (S-mRNA) which codes for the S-COMT polypeptide only. Here we demonstrate that the P2 promoter controls the expression of alternatively spliced 1.9 kb transcripts (MB-mRNA) which differ by a 27-nucleotide region immediately upstream of the MB-AUG codon. The presence of the 27-base sequence alters the nucleotide at position -3 from G to C, thereby changing the translation initiation context of the MB-AUG codon. Expression experiments in COS-7 cells using full-length COMT cDNAs showed that this alteration affected the initiation of the translation of the MB-AUG and consequently changed the relative amounts of MB- and S-COMT polypeptides produced. No proteolytic cleavage of the MB-COMT form to S-COMT was detected in in vitro or in vivo pulse-chase experiments. We conclude that the bifunctional 1.9 kb mRNAs are able to produce both S-COMT and MB-COMT polypeptide by the leaky scanning mechanism of translation initiation.[1]

References

 
WikiGenes - Universities