Polydom: a secreted protein with pentraxin, complement control protein, epidermal growth factor and von Willebrand factor A domains

• Published in: Biochemical journal Vol. 352 Pt 1; no. 1; pp. 49 - 59
• Main Authors: Gilgès, D, Vinit, M A, Callebaut, I, Coulombel, L, Cacheux, V, Romeo, P H, Vigon, I
• Format: Journal Article
• Language: English
• Published: England Portland Press 15.11.2000
• Subjects: Amino Acid Sequence; Animals; Biochemistry; Biochemistry, Molecular Biology; Blotting, Northern; Blotting, Western; Bone Marrow Cells - metabolism; C-Reactive Protein - chemistry; C-Reactive Protein - genetics; C-Reactive Protein - metabolism; Cell Adhesion; Cellular Biology; Chromosome Mapping; Chromosomes, Human, Pair 9; Cloning, Molecular; Collagen - chemistry; DNA, Complementary - metabolism; Epidermal Growth Factor - chemistry; Epidermal Growth Factor - genetics; Epidermal Growth Factor - metabolism; Extracellular Matrix Proteins - chemistry; Extracellular Matrix Proteins - metabolism; Humans; In Situ Hybridization, Fluorescence; Life Sciences; Mice; Models, Molecular; Molecular Sequence Data; Nerve Tissue Proteins - metabolism; Placenta - metabolism; Protein Sorting Signals; Protein Structure, Tertiary; Proteins; Reverse Transcriptase Polymerase Chain Reaction; Sequence Analysis, DNA; Sequence Homology, Amino Acid; Structural Biology; Time Factors; Tissue Distribution; Transfection; von Willebrand Factor - chemistry; von Willebrand Factor - genetics; von Willebrand Factor - metabolism
• ISSN: 0264-6021; 1470-8728
• DOI: 10.1042/0264-6021:3520049

To identify extracellular proteins with epidermal growth factor (EGF) domains that are potentially involved in the control of haemopoiesis, we performed degenerate reverse-transcriptase-mediated PCR on the murine bone-marrow stromal cell line MS-5 and isolated a new partial cDNA encoding EGF-like domains related to those in the Notch proteins. Cloning and sequencing of the full-length cDNA showed that it encoded a new extracellular multi-domain protein that we named polydom. This 387 kDa mosaic protein contained a signal peptide followed by a new association of eight different protein domains, including a pentraxin domain and a von Willebrand factor type A domain, ten EGF domains, and 34 complement control protein modules. The human polydom mRNA is strongly expressed in placenta, its expression in the other tissues being weak or undetectable. The particular multidomain structure of the encoded protein suggests an important biological role in cellular adhesion and/or in the immune system.