title: Molecular cloning of Porimin, a novel cell surface receptor mediating oncotic cell death.
abstract: Anti-Porimin (Pro-oncosis receptor inducing membrane injury) mAb mediates oncosis-like cell death in Jurkat cells. Porimin cDNA was isolated from a Jurkat cell cDNA library by COS cell-expression cloning. The 3,337-bp cDNA has an ORF of 567 bp, encoding a type I transmembrane protein of 189 amino acids. The extracellular domain of Porimin contains many O-linked and seven N-linked glycosylation sites that define it as a new member of the mucin family. COS7 and 293 cells transiently transfected with Porimin cDNA were specifically recognized by anti-Porimin Ab in cell staining and immunoblotting experiments. When expressed in Jurkat cells, a His-tagged Porimin cDNA construct resulted in the generation of a specific 110-kDa-size protein that matched the molecular mass of the endogenous Porimin protein. Crosslinking of the Porimin receptor expressed on COS7 transfectants resulted in the loss of cell membrane integrity and cell death as measured by the leakage of intracellular lactate dehydrogenase. Both COS7 and 293 cells expressing transfected Porimin at a relatively high level lost their ability to adhere to culture dishes, suggesting a role for Porimin in cell adhesion. The Porimin gene was mapped to human chromosome 11q22.1 and is composed of four exons spanning 133 kb of genomic DNA.
authors.affiliation: Division of Tumor Immunology, Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: F
authors.initials: F
authors.lastname: Ma
authors.forename: C
authors.initials: C
authors.lastname: Zhang
authors.forename: K V
authors.initials: KV
authors.lastname: Prasad
authors.forename: G J
authors.initials: GJ
authors.lastname: Freeman
authors.forename: S F
authors.initials: SF
authors.lastname: Schlossman
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D019556:COS Cells; D002448:Cell Adhesion / Q000502:physiology; D016923:Cell Death / Q000502:physiology*; D002460:Cell Line; D002522:Chlorocebus aethiops; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics; D005091:Exons / Q000235:genetics; D015723:Gene Library; D005796:Genes; D006031:Glycosylation; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D019169:Jurkat Cells / Q000166:cytology; D007770:L-Lactate Dehydrogenase / Q000032:analysis; D008565:Membrane Proteins; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009077:Mucins / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D005810:Multigene Family; D009363:Neoplasm Proteins / Q000235:genetics / Q000502:physiology; D012333:RNA, Messenger / Q000032:analysis; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification* / Q000502:physiology; D014162:Transfection
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D009077:Mucins; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; C434731:TMEM123 protein, human; D007770:L-Lactate Dehydrogenase