MTPN Full-Length MS Protein Standard (NP_665807), Labeled with [U- 13C6, 15N4]-L-Arginine and [U- 13C6, 15N2]-L-Lysine, was produced in human 293 cells (HEK293) with fully chemically defined cell culture medium to obtain incorporation efficiency at Creative-Proteomics. The transcript produced from this gene is bi-cistronic and can encode both myotrophin and leucine zipper protein 6. The myotrophin protein is associated with cardiac hypertrophy, where it is involved in the conversion of NFkappa B p50-p65 heterodimers to p50-p50 and p65-p65 homodimers. This protein also has a potential function in cerebellar morphogenesis, and it may be involved in the differentiation of cerebellar neurons, particularly of granule cells. A cryptic ORF at the 3 end of this transcript uses a novel internal ribosome entry site and a non-AUG translation initiation codon to produce leucine zipper protein 6, a 6.4 kDa tumor antigen that is associated with myeloproliferative disease.