The human T-cell leukemia virus type I Tax protein induces apoptosis which is blocked by the Bcl-2 protein.
The Tax protein of human T-cell leukemia virus type I activates transcription of cellular and viral genes and can immortalize primary T lymphocytes. We have previously reported that the Tax protein transforms Rat-1 cells. Here we show that Tax-transformed Rat-1 cells detach from plates to undergo apoptotic cell death by serum deprivation. These cells exhibit DNA fragmentation into oligonucleosomal fragments and chromatin condensation. Constitutive expression of a proto-oncogene, bcl-2, effectively blocks Tax-mediated apoptosis caused by serum deprivation without affecting the levels of Tax expression and the transformed phenotype of the cells.
Yamada
T
T
Institute for Virus Research, Kyoto University, Japan.
Yamaoka
S
S
Goto
T
T
Nakai
M
M
Tsujimoto
Y
Y
Hatanaka
M
M
D000818:Animals; D017209:Apoptosis; D002471:Cell Transformation, Neoplastic; D016895:Culture Media, Serum-Free; D005347:Fibroblasts / Q000502:physiology; D005434:Flow Cytometry; D016356:Gene Products, tax / Q000494:pharmacology*; D015368:Human T-lymphotropic virus 1; D006801:Humans; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins / Q000494:pharmacology*; D019253:Proto-Oncogene Proteins c-bcl-2; D051381:Rats; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000494:pharmacology; D014162:Transfection
D016895:Culture Media, Serum-Free; D016356:Gene Products, tax; C000715470:MAS1 protein, human; D000090063:Proto-Oncogene Mas; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D011994:Recombinant Proteins