Identification of a protein increasing in serum of Nagase analbuminemic rats bearing intestinal tumors as an isotype of T-kininogen.
Increase in an unidentified protein was observed in serum of Nagase analbuminemic rats (NAR) bearing intestinal tumors induced by azoxymethane. This protein seemed to be a polymer of a protein of 73 kDa as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and so was tentatively named 73K-protein. The serum concentration of 73K-protein in NAR bearing intestinal tumors was 11.9 +/- 2.2 mg/ml (mean +/- SD, n = 5), whereas that in control NAR was 2.0 +/- 0.2 mg/ml. Increase of the serum 73K-protein level was also observed in Sprague-Dawley rats bearing intestinal tumors, skin tumors, subcutaneous sarcomas, or mammary tumors and in ACI rats bearing urinary bladder tumors. On double immunodiffusion analysis, the 73K-protein was not detected in mouse, guinea pig, pig, horse, or human serum. A cDNA clone bearing the sequence encoding 73K-protein was isolated from a cDNA library constructed from rat liver mRNA. The nucleotide sequence of the 73K-protein showed 98.8% and 96.9% homologies with the sequences of the 3'-proximal domains of the cDNAs for TI- and TII-kininogen, respectively. Therefore, the 73K-protein was concluded to be an isotype of T-kininogen.
Kanda
S
S
Department of Chemistry, Sasaki Institute, Tokyo.
Sugiyama
K
K
Takahashi
M
M
Shumiya
S
S
Tomino
S
S
Nagase
S
S
D000595:Amino Acid Sequence; D000818:Animals; D001397:Azoxymethane; D001483:Base Sequence; D001798:Blood Proteins / Q000378:metabolism*; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D005779:Immunodiffusion; D007414:Intestinal Neoplasms / Q000097:blood* / Q000139:chemically induced / Q000150:complications; D007704:Kininogens / Q000097:blood*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D051381:Rats; D011919:Rats, Inbred Strains; D011922:Rats, Mutant Strains; D012709:Serum Albumin / Q000172:deficiency*
D001798:Blood Proteins; D007704:Kininogens; D012709:Serum Albumin; D004247:DNA; D001397:Azoxymethane