The role of the IGF-1 receptor in the stimulation of cells by short pulses of growth factors.
Balb/c 3T3 cells require prolonged stimulation by serum or growth factors to enter DNA synthesis. However, in p6 cells, a derivative cell line from 3T3 cells which constitutively over-express the insulin-like growth factor-1 (IGF-1) receptor, a serum pulse of only 1 h is sufficient for maximal stimulation. Furthermore, maximal stimulation of DNA synthesis is also obtained when 3T3 cells, serum-stimulated for only 1 h, are subsequently incubated with IGF-1. Our results indicate that short pulses of growth factors render 3T3 cells capable of responding to IGF-1, either by increasing the number of IGF-1 receptors or by providing a new substrate for the activated receptor.
Yoshinouchi
M
M
Jefferson Cancer Institute, Thomas Jefferson University, Philadelphia, PA 19107-5541.
Baserga
R
R
D016475:3T3 Cells; D000818:Animals; D002453:Cell Cycle; D002455:Cell Division; D006133:Growth Substances / Q000378:metabolism / Q000494:pharmacology*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000494:pharmacology*; D051379:Mice; D008807:Mice, Inbred BALB C; D011673:Pulsatile Flow; D017526:Receptor, IGF Type 1 / Q000235:genetics / Q000502:physiology*
D006133:Growth Substances; D007334:Insulin-Like Growth Factor I; D017526:Receptor, IGF Type 1