Sequence and expression of Tangier apoA-I gene.
We have isolated and characterized the apoA-I gene from a lambda 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.
D000595:Amino Acid Sequence; D016632:Apolipoprotein A-I; D001054:Apolipoproteins A / Q000235:genetics*; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D004247:DNA / Q000032:analysis; D005786:Gene Expression Regulation; D005796:Genes; D007009:Hypolipoproteinemias / Q000235:genetics*; D008214:Lymphocytes / Q000032:analysis; D008969:Molecular Sequence Data; D009154:Mutation; D012333:RNA, Messenger / Q000378:metabolism; D013631:Tangier Disease / Q000235:genetics*; D014162:Transfection
D016632:Apolipoprotein A-I; D001054:Apolipoproteins A; D012333:RNA, Messenger; D004247:DNA