-transparent.png){kind=logo}
Hormones and growth factors regulate cell growth via the mitogen-activated protein (MAP) kinase cascade. Here we examine the actions of the hormone somatostatin on the MAP kinase cascade through one of its two major receptor subtypes, the somatostatin receptor 1 (SSTR1) stably expressed in CHO-K1 cells. Somatostatin antagonizes the proliferative effects of fibroblast growth factor in CHO-SSTR1 cells via the SSTR1 receptor. However, in these cells, somatostatin robustly activates MAP kinase (also called extracellular signal regulated kinase; ERK) and augments fibroblast growth factor-stimulated ERK activity. We show that the activation of ERK via SSTR1 is pertussis toxin sensitive and requires the small G protein Ras, phosphatidylinositol 3-kinase, the serine/threonine kinase Raf-1, and the protein tyrosine phosphatase SHP-2. The activation of ERK by SSTR1 increased the expression of the cyclin-dependent protein kinase inhibitor p21(cip1/WAF1). Previous studies have suggested that somatostatin-stimulated protein tyrosine phosphatase activity mediates the growth effects of somatostatin. Our data suggest that SHP-2 stimulation by SSTR1 may mediate some of these effects through the activation of the MAP kinase cascade and the expression of p21(cip1/WAF1).
T Florio, and
H Yao, and
K D Carey, and
T J Dillon, and
P J Stork
December 1998,
Annals of the New York Academy of Sciences,
T Florio, and
H Yao, and
K D Carey, and
T J Dillon, and
P J Stork
September 2001,
The Journal of neuroscience : the official journal of the Society for Neuroscience,
T Florio, and
H Yao, and
K D Carey, and
T J Dillon, and
P J Stork
September 1994,
Biochemical and biophysical research communications,
T Florio, and
H Yao, and
K D Carey, and
T J Dillon, and
P J Stork
November 2013,
The Journal of biological chemistry,
T Florio, and
H Yao, and
K D Carey, and
T J Dillon, and
P J Stork
November 2001,
The Journal of biological chemistry,
T Florio, and
H Yao, and
K D Carey, and
T J Dillon, and
P J Stork
January 2006,
Methods in molecular biology (Clifton, N.J.),
T Florio, and
H Yao, and
K D Carey, and
T J Dillon, and
P J Stork
December 1998,
The Biochemical journal,
T Florio, and
H Yao, and
K D Carey, and
T J Dillon, and
P J Stork
September 2002,
Molecular biology of the cell,
T Florio, and
H Yao, and
K D Carey, and
T J Dillon, and
P J Stork
November 2004,
Journal of cardiovascular pharmacology,
T Florio, and
H Yao, and
K D Carey, and
T J Dillon, and
P J Stork
October 2009,
Molecular pharmacology,
