title: Isolation and characterization of a complementary DNA (PD-1) differentially expressed by human pancreatic ductal cell tumors.
abstract: A complementary DNA (cDNA) library from a cloned subline (CD-11) of a well differentiated human pancreatic tumor cell line, HPAF, was subjected to differential screening using single stranded cDNA probes synthesized from mRNA of the well differentiated cell clone CD-11 and a poorly differentiated pancreatic tumor cell line, Panc 1. A cDNA clone (PD-1) was identified which had an insert of 626 base pairs (bp). PD-1 cDNA hybridized to a transcript of about 650 bp on Northern blot analysis, suggesting that the cDNA was close to full length. Densitometric analysis of Northern blots showed that a well differentiated pancreatic tumor line had a 5-fold higher PD-1 expression as compared to the poorly differentiated line, Panc 1. Nucleotide sequence analysis of the PD-1 cDNA and its deduced amino acid sequence showed an open reading frame of 399 bp. In addition to the open reading frame, the sequence had a 5' untranslated region of 61 bp and a 3' untranslated tail of 147 bp. The nucleotide sequence did not show any significant homology to any other sequence in the GENBANK or EMBL databases; however, the translated protein showed 35% homology to bacterial ribosomal proteins over 112 amino acids. Sequence analysis of the PD-1 cDNA and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of its in vitro transcription/translation product suggest that this gene encoded a protein of 16,000 daltons.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Microbiology and Immunology, Duke University Medical Center, Durham, North Carolina 27710.
authors.forename: S K
authors.initials: SK
authors.lastname: Batra
authors.forename: R S
authors.initials: RS
authors.lastname: Metzgar
authors.forename: M A
authors.initials: MA
authors.lastname: Hollingsworth
mesh_terms: D000595:Amino Acid Sequence; D015703:Antigens, CD; D000954:Antigens, Surface; D051017:Apoptosis Regulatory Proteins; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D002454:Cell Differentiation / Q000235:genetics; D015342:DNA Probes / Q000235:genetics; D004273:DNA, Neoplasm / Q000235:genetics*; D015870:Gene Expression / Q000502:physiology; D006801:Humans; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000235:genetics*; D016366:Open Reading Frames / Q000235:genetics; D010183:Pancreatic Ducts / Q000473:pathology; D010190:Pancreatic Neoplasms / Q000235:genetics* / Q000473:pathology; D061026:Programmed Cell Death 1 Receptor; D011506:Proteins; D012269:Ribosomal Proteins / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid; D014407:Tumor Cells, Cultured
chemical_list: D015703:Antigens, CD; D000954:Antigens, Surface; D051017:Apoptosis Regulatory Proteins; D015342:DNA Probes; D004273:DNA, Neoplasm; D009363:Neoplasm Proteins; C105992:PDCD1 protein, human; D061026:Programmed Cell Death 1 Receptor; D011506:Proteins; D012269:Ribosomal Proteins