Comparative sequence and expression analyses of African green monkey (Cercopithecus aethiops) TNPO3 from CV-1 cells

摘要

Transportin 3 (TNPO3 or TRN-SR2) is a key host cellular factor involved in the early steps of several lentiviral replications. In the present study, we cloned the TNPO3 gene from CV-1 cells of African green monkey (AGM) using a homologue based cloning technology, analyzed the sequence, and evaluated the cellular expression of the proteins by western blotting and immunostaining assays. DNA sequencing of TNPO3 showed homologies of 99 % with human, rhesus monkey, chimpanzee, and baboon; the predicted protein sequence differed in only one amino acid (leucine in place of methionine). The deduced sequence revealed that AGM is phylogenetically related to human, chimpanzee, rhesus monkey, orangutan and baboon rather than bovine, rate and mouse. Western blot analysis demonstrated immunoreactive proteins in both the cytoplasmic and nuclear fractions. A similar expression pattern was observed in human and baby hamster cells. The specific detection of TNPO3 was also confirmed in the cytoplasm and nucleus by immunostaining. The present findings conclusively demonstrate that AGM-TNPO3 is genetically and physiologically almost identical with that of humans and could be a good candidate for HIV and AGM research as well as an ideal system for a TNPO3 vaccine trial.