Identification, characterization and expression profiles of PSEN2 in the Chinese tree shrew ().

Abstract

The geneencodes presenilin-2, a subunit of γ-secretase. Mutations inare not only related to Alzheimer's disease but are also involved in other diseases. The Chinese tree shrew () is a potential animal model for Alzheimer's disease, although little is known about its cDNA sequence, protein structure, andexpression. To better understandin the tree shrew, we cloned this gene by rapid amplification of cDNA ends technology. Hence, we analyzed the sequence and molecular characteristics of PSEN2 mRNA, predicted its spatial structure, and analyzed its expression profiles. We found that tree shrewis 1539 base pairs in length and encodes 330 amino acids. It is homologous and genetically similar to humans (97.64% identity). The protein structure of tree shrew PSEN2 indicated similarities to human PSEN2, both being comprised of numerous transmembrane helices. However, tree shrew PSEN2 possesses seven α-helices, and thus lacks three compared with human PSEN2. Tree shrew PSEN2 mRNAs were ubiquitously detected in all tissues, with a tissue- and temporal-specific pattern. These results pave the way towards the function of tree shrew PSEN2, which will give insights into the mechanisms leading to neurodegenerative and other diseases in humans.