title: Isolation of a cDNA clone encoding the amino-terminal region of human apolipoprotein B.
abstract: A partial cDNA clone for the B-26 region of apolipoprotein B was isolated from an adult human liver DNA library by screening with an oligonucleotide probe derived from amino-terminal protein sequence obtained from purified B-26 peptide. Antisera against a synthetic 17-residue peptide whose amino acid sequence was encoded by the clone cross-reacts with apolipoproteins B-26, B-100, and B-48, but not with B-74. The nucleotide sequence immediately upstream from the amino terminus of B-26 codes for an apparent signal sequence, implying that the B-26 moiety is in an amino-terminal locus in the B-100 protein. That this sequence represents a 5' end region is further supported by primer extension analysis using a fragment of the cDNA clone and by S1 nuclease protection experiments using the corresponding region in a genomic clone.
mesh_terms: D000595:Amino Acid Sequence; D001055:Apolipoproteins B / Q000235:genetics* / Q000276:immunology; D001483:Base Sequence; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D005796:Genes; D006801:Humans; D007163:Immunosorbent Techniques; D012333:RNA, Messenger / Q000235:genetics
chemical_list: D001055:Apolipoproteins B; D012333:RNA, Messenger; D004247:DNA