werner@aecom.UUCP (Craig Werner) (12/01/86)
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! Pertussis Toxin-Sensitive Pathway in the Stimulation of c-myc
! Expression and DNA Synthesis by Bombesin.
! Letterio JJ, Coughlin SR, Williams LT
! Science 234:1117 (28 Nov 1986)
The bombesin-like peptides are potent mitogens for Swiss 3T3
fibroblasts, human bronchial epithelial cells, and cells isolated from
small cell carcinoma of the lung. The mechanism of signal transduction
in the proliferative response to bombesin was investigated by studying
the effect of Bordetella pertussis toxin on bombesin-stimulated
mitogenesis. At nanomolar concentrations, bombesin increased levels of
c-myc messenter RNA and stimulated DNA synthesis in Swiss 3T3 cells.
Treatment of the cells with pertussis toxin (5 nanograms per milliliter)
completely blocked bombesin-enhanced c-myc expression and eliminated
bombesin-stimulated DNA synthesis. This treatment had essentially no
effect on the mitogenic responses to either platelet-derived growth
factor or phorbol 12,13-dibutyrate. The results suggest that the
mitogenic actions of bombesin-like growth factor are mediated through a
pertussis toxin-sensitive guanine nucleotide-binding protein.
Furthermore they indicate that bombesin-like growth factors act through
pathways that are different from those activated by platelet-derived
growth factor.
--
Craig Werner (MD/PhD '91)
!philabs!aecom!werner
(1935-14E Eastchester Rd., Bronx NY 10461, 212-931-2517)
"The proper delivery of medical care is to do as much Nothing as possible"