Primary structure of a mouse mastocytoma proteoglycan core protein

• DOI: 10.1042/bj2630105
• Publication Date: 2015-08-10T21:14:21Z
• Authors: L Kjellén; I Pettersson; P Lillhager; M L Steen; U Pettersson; P Lehtonen; T Karlsson; E Ruoslahti; L Hellman
• Keywords: 0301 basic medicine; Extracellular Matrix Proteins; Base Sequence; Molecular Sequence Data; Mast-Cell Sarcoma; Nucleic Acid Hybridization; DNA; DNA, Neoplasm; Blotting, Northern; Bacteriophage lambda; Neoplasm Proteins; Blotting, Southern; Mice; 03 medical and health sciences; Microsomes; Animals; Electrophoresis, Polyacrylamide Gel; Lectins, C-Type; Aggrecans; Amino Acid Sequence; DNA Probes; Glycoproteins

The complete nucleotide sequence of a mouse mastocytoma proteoglycan core protein mRNA was determined. The mRNA, estimated to contain 1.1 kb, encodes a protein with an Mr of 16715. A 21-amino acid-residue region of the protein is composed of alternating serine and glycine residues. Southern-blot analysis of mouse genomic DNA with cDNA containing sequences corresponding to the Ser-Gly repeat region revealed more than 15 gene fragments. Hybridization with a probe corresponding to the N-terminal portion of the core protein identified two fragments, and cDNA covering the C-terminal part of the core protein and the 3′ untranslated part of the mRNA hybridized to a single fragment. Antibodies against the core protein, obtained after immunization of rabbits with a fusion protein, reacted with both chondroitin sulphate proteoglycans and heparin proteoglycans produced by the tumour. In immunoblotting of a microsomal fraction from the mastocytoma, the antiserum recognized a single protein (Mr 17,000), which probably represents the core protein before glycosylation.