TY - JOUR
T1 - Identity of urinary trypsin inhibitor-binding protein to link protein
AU - Kobayashi, Hiroshi
AU - Hirashima, Yasuyuki
AU - Sun, Guang Wei
AU - Fujie, Michio
AU - Nishida, Takashi
AU - Takigawa, Masaharu
AU - Terao, Toshihiko
PY - 2000/7/14
Y1 - 2000/7/14
N2 - Urinary trypsin inhibitor (UTI), a Kunitz-type protease inhibitor, directly binds to some types of cells via cell-associated UTI-binding proteins (UTI-BPs). Here we report that the 49-kDa protein (UTI-BP40) was purified from the cultured human chondrosarcoma cell line HCS-2/8 by UTI affinity chromatography. Purified UTI- BP40 was digested with trypsin, and the amino acid sequences of the peptide fragments were determined. The sequences of six tryptic fragments of UTI-BP40 were identical to subsequences present in human link protein (LP). Authentic bovine LP and UTI- BP40 displayed identical electrophoretic and chromatographic behavior. The UTI-binding properties of UTI-BP40 and LP were indistinguishable. Direct binding and competition studies strongly demonstrated that the NH2-terminal fragment is the UTI-binding part of the LP molecule, that the COOH-terminal UTI fragment (HI-8) failed to bind the NH2-terminal subdomain of the LP molecule, and that LP and UTI-BP40 exhibited significant hyaluronic acid binding. These results demonstrate that UTI-BP40 is identical to LP and that the NH2-terminal domain of UTI is involved in the interaction with the NH2-terminal fragment of LP, which is bound to hyaluronic acid in the extracellular matrix.
AB - Urinary trypsin inhibitor (UTI), a Kunitz-type protease inhibitor, directly binds to some types of cells via cell-associated UTI-binding proteins (UTI-BPs). Here we report that the 49-kDa protein (UTI-BP40) was purified from the cultured human chondrosarcoma cell line HCS-2/8 by UTI affinity chromatography. Purified UTI- BP40 was digested with trypsin, and the amino acid sequences of the peptide fragments were determined. The sequences of six tryptic fragments of UTI-BP40 were identical to subsequences present in human link protein (LP). Authentic bovine LP and UTI- BP40 displayed identical electrophoretic and chromatographic behavior. The UTI-binding properties of UTI-BP40 and LP were indistinguishable. Direct binding and competition studies strongly demonstrated that the NH2-terminal fragment is the UTI-binding part of the LP molecule, that the COOH-terminal UTI fragment (HI-8) failed to bind the NH2-terminal subdomain of the LP molecule, and that LP and UTI-BP40 exhibited significant hyaluronic acid binding. These results demonstrate that UTI-BP40 is identical to LP and that the NH2-terminal domain of UTI is involved in the interaction with the NH2-terminal fragment of LP, which is bound to hyaluronic acid in the extracellular matrix.
UR - http://www.scopus.com/inward/record.url?scp=0034647913&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0034647913&partnerID=8YFLogxK
U2 - 10.1074/jbc.M907862199
DO - 10.1074/jbc.M907862199
M3 - Article
C2 - 10801881
AN - SCOPUS:0034647913
VL - 275
SP - 21185
EP - 21191
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 28
ER -