Apolipoprotein AV (apoAV) modulates plasma
triglyceride levels, which is an independent risk factor for
cardiovascular disease. ApoAV is also involved in
atherosclerosis lesion formation. In order to systematically evaluate the
apolipoprotein-related gene profile in tree shrew, a model for its insusceptibility to
atherosclerosis, we performed apoAV cloning and characterization. The full-length
cDNA of apoAV was identified using SMART-RACE. ApoAV
cDNA sequence revealed two transcripts, 1,948 and 1,397 base pairs, due to alternative polyadenylation. These two transcripts share the same open reading frame (ORF), which encodes a 369-amino
acid protein with high identity to human apoAV (75 %), including a 23-amino
acid N-terminal
signal peptide. ApoAV is expressed exclusively in the liver. Mature apoAV was expressed in E. coli BL21(DE3) and purified by Ni-chelated resin.
Lipoprotein lipase activity was significantly stimulated by this
recombinant protein. The full-length ORF of apoAV was cloned into pDsRed-monomer-N1 vector with a
red fluorescent protein tag and was primarily localized in cytoplasm of hepG2 cells. The successful cloning, expression and localization of apoAV in tree shrew has laid down the foundation for further investigation on its structure and functions.