cDNA cloning of human apoA-I: amino acid sequence of preproapoA-I.
ds-cDNA to human liver apoA-I mRNA has been cloned. Nucleic acid sequence analysis revealed that apoA-I mRNA codes for a precursor apolipoprotein, preproapoA-I, which contains 24 amino acids on the NH2-terminal end of the mature plasma apoA-I. Eighteen amino acids are contained within the hydrophobic prepeptide (Met-Lys-Ala-Ala-Val-Leu-Thr-Leu-Ala-Val-Leu-Phe-Leu-Thr-Gly-Ser-Gln-Ala) followed by a 6 amino acid propeptide (Arg-His-Phe-Trp-Gln-Gln). Our results on human apoA-I are in agreement with the partial sequence of the precursor of rat apoA-I with respect to the length of the precursor sequence, location of the prepeptide, and the presence of an unusual propeptide sequence terminating in a neutral dipeptide Gln-Gln. A detailed analysis of the primary structure of normal human apoA-I mRNA will be essential to our ultimate understanding of the processing of human apoA-I and diseases characterized by molecular defects in apoA-I structure and function.
D000595:Amino Acid Sequence; D016632:Apolipoprotein A-I; D001053:Apolipoproteins / Q000096:biosynthesis*; D001054:Apolipoproteins A; D001345:Autoradiography; D003001:Cloning, Molecular; D004247:DNA; D006801:Humans; D008099:Liver / Q000378:metabolism; D011498:Protein Precursors / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000378:metabolism
D016632:Apolipoprotein A-I; D001053:Apolipoproteins; D001054:Apolipoproteins A; D011498:Protein Precursors; D012333:RNA, Messenger; C035250:preproapolipoprotein A-I; D004247:DNA