Thymidine phosphorylase activity associated with platelet-derived endothelial cell growth factor.
Partial complementary DNA (cDNA) for thymidine phosphorylase (dThdPase) was cloned by means of a polymerase chain reaction. There was complete sequence identity between the amino acid sequence deduced from the nucleotide sequence of a clone (288 nucleotides) and the residues of platelet-derived endothelial cell growth factor (PD-ECGF). The amino acid sequence of all four peptide fragments from purified human dThdPase could be aligned with that of PD-ECGF. Our data indicate that residues 125-244 of PD-ECGF are identical to the sequence of human dThdPase. The molecular weights of human dThdPase and recombinant PD-ECGF (rPD-ECGF) that lacks 10 amino acids at the amino terminal were 55 and 52 kDa, respectively. Anti-PD-ECGF antibody recognized dThdPase, and anti-dThdPase antibody recognized rPD-ECGF. rPD-ECGF had dThdPase activity and its specific activity was similar to that of purified human dThdPase. dThdPase activity and molecules were detected in COS cells transfected with human PD-ECGF cDNA, but not in nontransfected cells. The sizes of PD-ECGF and dThdPase in the transfected COS cells were identical. These data suggest that human dThdPase is identical to PD-ECGF.
Sumizawa
T
T
Department of Cancer Chemotherapy, Institute of Cancer Research, Faculty of Medicine, Kagoshima University.
Furukawa
T
T
Haraguchi
M
M
Yoshimura
A
A
Takeyasu
A
A
Ishizawa
M
M
Yamada
Y
Y
Akiyama
S
S
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D006801:Humans; D015151:Immunoblotting; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011233:Precipitin Tests; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013939:Thymidine Phosphorylase / Q000737:chemistry* / Q000378:metabolism; D014162:Transfection
D018076:DNA, Complementary; D013939:Thymidine Phosphorylase