title: Molecular cloning of a cDNA for human pregnancy-specific beta 1-glycoprotein:homology with human carcinoembryonic antigen and related proteins.
abstract: Human pregnancy-specific beta 1-glycoprotein (SP1) plays an essential role in normal pregnancy. It is also a well-characterized oncodevelopmental antigen, expressed aberrantly by all trophoblastic tumors and some other malignant cell types. Here we report the identification of a human placental cDNA encoding the SP1 polypeptide sequence. The coding sequence shows 95% identity at the nucleotide level with a distinct, recently published SP1 cDNA sequence (PSG16). Unexpectedly, the sequence is also highly homologous to the published sequence of human carcinoembryonic antigen (CEA). SP1, CEA and CEA-related nonspecific cross-reacting species thus belong to a group of closely related though antigenically diverse tumor-associated glycoproteins. Comparison of the deduced amino acid sequence of the SP1 cDNA with that of CEA provides insight into the modular nature of these related proteins. This may have implications for the genomic organization and evolution of the CEA gene family.
authors.affiliation: Department of Biochemistry, University of Aberdeen, Marischal College, U.K.
authors.forename: B C
authors.initials: BC
authors.lastname: Rooney
authors.forename: C H
authors.initials: CH
authors.lastname: Horne
authors.forename: N
authors.initials: N
authors.lastname: Hardman
mesh_terms: D000595:Amino Acid Sequence; D000951:Antigens, Neoplasm / Q000235:genetics; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D002272:Carcinoembryonic Antigen / Q000235:genetics*; D015815:Cell Adhesion Molecules; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics*; D005260:Female; D006023:Glycoproteins / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D015345:Oligonucleotide Probes / Q000138:chemical synthesis; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000235:genetics*; D011268:Pregnancy-Specific beta 1-Glycoproteins / Q000235:genetics*; D012689:Sequence Homology, Nucleic Acid; D014357:Trypsin / Q000378:metabolism
chemical_list: D000951:Antigens, Neoplasm; D002272:Carcinoembryonic Antigen; D015815:Cell Adhesion Molecules; D006023:Glycoproteins; D015345:Oligonucleotide Probes; D011257:Pregnancy Proteins; D011268:Pregnancy-Specific beta 1-Glycoproteins; D004247:DNA; D014357:Trypsin