Cloning and characterization of a human cDNA encoding a novel putative cytoplasmic protein-tyrosine-phosphatase.
We have cloned and characterized a human cDNA encoding a new member of the family of cytosolic type protein-tyrosine-phosphatase (PTP), designated as PTPG1, from an adult colon tissue cDNA library by using the PCR product as probe. We obtained 5 cDNA clones, which cover the predicted open reading frame encoding a 88-kDa protein composed of 780 amino acids, and it had no apparent signal or transmembrane sequences, suggesting that it is a cytosolic protein. The N-terminal region had a PTP catalytic domain that is 30-40% identical to previously reported human PTPs. This revealed that the enzyme composes an additional family of human PTPs. PTPG1 was characterized by a long non-enzymatic domain located at the C-terminus, including PEST sequences which are characteristic for short half-life proteins in eukaryotes. Northern blot analysis of PTPG1 mRNA showed a 4.6-kb transcript that was detected in a wide variety of cell lines to suggest its extensive expression.
Takekawa
M
M
Department of internal medicine (Section 1), Sapporo Medical College, Japan.
Itoh
F
F
Hinoda
Y
Y
Arimura
Y
Y
Toyota
M
M
Sekiya
M
M
Adachi
M
M
Imai
K
K
Yachi
A
A
D000595:Amino Acid Sequence; D016375:Antisense Elements (Genetics); D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D003001:Cloning, Molecular; D003106:Colon / Q000201:enzymology*; D003600:Cytosol / Q000201:enzymology; D004247:DNA / Q000235:genetics*; D015723:Gene Library; D006801:Humans; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D016366:Open Reading Frames; D016133:Polymerase Chain Reaction; D017027:Protein Tyrosine Phosphatases / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000302:isolation & purification; D017386:Sequence Homology, Amino Acid
D016375:Antisense Elements (Genetics); D009838:Oligodeoxyribonucleotides; D012333:RNA, Messenger; D004247:DNA; D017027:Protein Tyrosine Phosphatases