Sequence and expression of Tangier apoA‐I gene

Open Access
Publisher Website
Google Scholar
Abstract
We have isolated and characterized the apoA‐I gene from a λ L47.1 genomic library constructed with DNA obtained from the lymphocytes of a Tangier disease patient. The DNA‐derived protein sequence of Tangier apoA‐I was found to be identical to normal apoA‐I. Transfection of mouse C127 cells with a recombinant vector containing the Tangier apoA‐I gene (pSV2‐gpt apoA‐I) allowed selection of stable clones resistant to aminopterin and mycophenolic acid. Analysis of these clones for apoA‐I synthesis showed that the protein secreted by cells expressing the Tangier apoA‐I gene was indistinguishable from the apoA‐I secreted by HepG2 cells. These experiments establish that the Tangier apoA‐I gene is structurally normal. It appears that the molecular basis of Tangier disease is not related to apoA‐I structure or regulation of expression, but rather to other factors pertinent to apoA‐I and high‐density lipoprotein metabolism.