Co-operation of simian virus 40 T antigen and insulin receptor substrate-1 in protection from apoptosis induced by interleukin-3 withdrawal.
32D cells are interleukin-3 (IL-3) dependent murine hemopoietic cells, that undergo apoptosis after IL-3 withdrawal. An overexpressed insulin-like growth factor I receptor (IGF-IR) protects these cells from apoptosis induced by IL-3 withdrawal. When 32D cells are stably transfected with plasmids expressing either IRS-1 (a major substrate of the IGF-IR) or the Simian virus 40 large T antigen, singly, they still undergo apoptosis after IL-3 withdrawal, although IRS-1 offers partial protection. The cells, however, are fully protected when they are stably transfected with both IRS-1 and SV40 T antigen. Protection from apoptosis in these cells is characterized by the stabilization of the Stat1 and Stat5 protein levels, whose synthesis is inhibited when IL-3 is withdrawn.
Zhou-Li
F
F
Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
Xu
S Q
SQ
Dews
M
M
Baserga
R
R
D000818:Animals; D000952:Antigens, Polyomavirus Transforming / Q000494:pharmacology / Q000502:physiology*; D017209:Apoptosis; D002455:Cell Division; D002460:Cell Line / Q000187:drug effects; D004268:DNA-Binding Proteins / Q000096:biosynthesis; D055504:Insulin Receptor Substrate Proteins; D007377:Interleukin-3 / Q000494:pharmacology*; D008715:Methionine / Q000032:analysis; D051379:Mice; D008894:Milk Proteins; D010750:Phosphoproteins / Q000494:pharmacology / Q000502:physiology*; D010957:Plasmids; D050794:STAT1 Transcription Factor; D050799:STAT5 Transcription Factor; D015534:Trans-Activators / Q000096:biosynthesis; D014162:Transfection
D000952:Antigens, Polyomavirus Transforming; D004268:DNA-Binding Proteins; D055504:Insulin Receptor Substrate Proteins; D007377:Interleukin-3; C526295:Irs1 protein, mouse; D008894:Milk Proteins; D010750:Phosphoproteins; D050794:STAT1 Transcription Factor; D050799:STAT5 Transcription Factor; C494080:Stat1 protein, mouse; D015534:Trans-Activators; D008715:Methionine