hpttg, a human homologue of rat pttg, is overexpressed in hematopoietic neoplasms. Evidence for a transcriptional activation function of hPTTG.
We have isolated a human cDNA clone encoding a novel protein of 22 kDa that is a human counterpart of the rat oncoprotein PTTG. We show that the corresponding gene (hpttg) is overexpressed in Jurkat cells (a human T lymphoma cell line) and in samples from patients with different kinds of hematopoietic malignancies. Analysis of the sequence showed that hPTTG has an amino-terminal basic domain and a carboxyl-terminal acidic domain, and that it is a proline-rich protein with several putative SH3-binding sites. Subcellular fractionation studies show that, although hPTTG is mainly a cytosolic protein, it is partially localized in the nucleus. In addition we demonstrate that the acidic carboxyl-terminal region of hPTTG acts as a transactivation domain when fused to a heterologous DNA binding domain, both in yeast and in mammalian cells.
Domínguez
A
A
Departamento de Microbiología, Facultad de Biología, Universidad de Sevilla, Spain.
Ramos-Morales
F
F
Romero
F
F
Rios
R M
RM
Dreyfus
F
F
Tortolero
M
M
Pintor-Toro
J A
JA
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015153:Blotting, Western; D019556:COS Cells; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D015972:Gene Expression Regulation, Neoplastic; D019337:Hematologic Neoplasms / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D019169:Jurkat Cells; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism*; D014176:Protein Biosynthesis; D051381:Rats; D012441:Saccharomyces cerevisiae / Q000235:genetics; D064249:Securin; D014158:Transcription, Genetic; D001616:beta-Galactosidase / Q000378:metabolism
D018076:DNA, Complementary; D009363:Neoplasm Proteins; D064249:Securin; C578002:pituitary tumor-transforming protein 1, human; D001616:beta-Galactosidase