Necdin Like Protein 2 (NDNL2)

By database searching for genes with sequence similarity to NDN, Chibuk et al. (2001) identified the NDNL2 gene on a BAC clone containing the APBA2 gene , which had been physically mapped to proximal 15q. The NDNL2 ORF, located within a single exon, predicted a 472-amino acid protein. The human and mouse proteins share 83% sequence identity, with maximum sequence conservation in the C terminus. Sequence analysis showed that mouse Ndnl2 is identical to the predicted protein Mageg1. Northern blot analysis detected expression of a 1.9-kb transcript in all human tissues tested, with highest expression in testis. Expression in mouse was also widespread. Studies in mouse and in sporadic Prader-Willi syndrome and Angelman syndrome patients indicated that expression of the NDNL2 gene is not imprinted.