Analysis suggests that the 477 amino acid protein isoform encoded by the P{UAS-nmo.c4-2} construct does not correspond to an isoform actually expressed in flies and is probably the result of an error at the moment of cDNA synthesis. The protein (see GenBank accession U12009.1) is not predicted in the D. melanogaster genome, or in any of the other sequenced Drosophila species and there is no other EST, besides the clone that the construct was made from, that encodes this isoform. The sequence of the clone used to generate the construct is almost the same as the mRNA that encodes the shortest nmo isoform, but it includes an extra base at the end of the coding region that produces a frameshift. As a result of this shift, the protein encoded by P{UAS-nmo.c4-2} has 63 more amino acids than the nmo short isoform. This change does not alter the kinase domain of nmo.

UASt regulatory sequences drive expression of a full length cDNA corresponding to nmo isoform c4-2.