Characterization of physiological function of the plasma proteins, PFBP and IHRP with knockout mice.

1) PHBPPHBP（血浆透明质酸结合蛋白）的研究是我们课题组1996年从人血浆中发现的。PHBP包含三个EGFs，一个Kringle和一个丝氨酸蛋白酶结构域，当特定肽键被劈裂时，它被激活以显示蛋白水解活性。为了阐明其功能，我们尝试构建PHBP基因敲除小鼠。在确定小鼠PHBP基因的基因组结构后，构建靶向载体，将新霉素耐受基因替换为第一个外显子的1kb区域。由于已经产生了PHBP基因敲除的胚胎干细胞克隆，因此正在努力培育敲除小鼠。”2) IHRPIHRP（Inter - a - trypsin inhibitor Heavy chain Related Protein，胰蛋白酶抑制剂重链相关蛋白）的研究是我课组1996年从人血浆中发现的。IHRP约70%的氨基酸序列与ITT重链具有同源性，但IHRP不具有ITT所具有的胰蛋白酶抑制活性。由于THRP的功能尚未被阐明，我们也试图产生IHRP基因敲除小鼠。目前我们已经确定了小鼠IHRP基因的结构以及小鼠IHRP mRNA的核苷酸序列。3) GBP - 28的研究在我们研究PHBP和IHRP的同时，我们也从人血浆中发现了GBP - 28。GBP 28 （28 kd明胶结合蛋白）是apM1 mRNA的翻译产物，该mRNA是Matsuzawa等人（大阪大学）发现的脂肪细胞特异性mRNA。松泽后来将这种蛋白质命名为脂联素。2001年，人们发现GBP 28/脂联素有可能成为抗糖尿病药物。目前，我们也在尝试生产ihrp基因敲除小鼠。

1) Studies on PHBPPHBP (Plasma Hyaluronan-Binding Protein)was found from human blood plasma by our group in 1996.PHBP contains three EGFs, a Kringle and a serine protease domains, and is activated to reveal proteolytic activity when a specific peptide bond is cleaved. To elucidate its functions, we tried to produce PHBP gene knockout mice. After the genomic structure of mouse PHBP gene was determined, a targeting vector was constructed to substitute a neomycin tolerant gene for a 1 kb region of the first exon. Since an ES cell clone which was knockout with PHBP gene was produced, we are trying to produce the knockout mice.2) Studies on IHRPIHRP(Inter a trypsin inhibitor Heavy chain Related Protein)was found from human blood plasma by our group in 1996.About 70% of IHRP has homology in amino acid sequence to ITT heavy chain while IHRP does not show the trypsin-inhibiting activity which ITT shows. As functions of THRP has been elucidated yet, we also tried to produce IHRP gene knockout mice. Presently we have determined the structure of mouse IHRP gene as well as the nucleotide sequence of mouse IHRP mRNA.3) Studies on GBP 28While we were working with PHBP and IHRP, we also found GBP 28 from human blood plasma. GBP 28 (gelatin binding protein of 28 kd) was the translated product of apM1 mRNA which was found as an adipocyte specific mRNA by Matsuzawa et al (Osaka univ.). Matsuzawa named this protein adiponectin later. In 2001, GBP 28/adiponectin was found to have a possibility for an anti diabetes drug. Presently we are also trying to produce IHRP-gene-knockout mice.