TY - JOUR
T1 - Neurotrophins
T2 - The biological paradox of survival factors eliciting apoptosis
AU - Casaccia-Bonnefil, Patrizia
AU - Kong, Haeyoung
AU - Chao, Moses V.
PY - 1998/5
Y1 - 1998/5
N2 - Neurotrophins are target-derived soluble polypeptides required for neuronal survival. Binding of neurotrophins to Trk receptor tyrosine kinases initiate signaling cascades that promote cell survival and differentiation. All family members bind to another receptor (p75(NTR)), which belongs to the tumor necrosis factor superfamily. Hence, nerve growth factor (NGF) and related trophic factors are unique in that two separate receptor types are utilized. Although the biological function of p75(NTR) has been elusive, it has been suggested to mediate apoptosis of developing neurons in the absence of Trk receptors. This presents a tantalizing paradigm, in which life-death decisions of cells are dependent upon the expression and action of two different receptors with distinctive signaling mechanisms. In the presence of TrkA receptors, p75 can participate in the formation of high affinity binding sites and enhanced NGF responsiveness leading to a survival signal. In the absence of TrkA receptors, p75 can generate, in only specific cell populations, a death signal. Here we discuss the unique features and implications of this unusual signal transduction system.
AB - Neurotrophins are target-derived soluble polypeptides required for neuronal survival. Binding of neurotrophins to Trk receptor tyrosine kinases initiate signaling cascades that promote cell survival and differentiation. All family members bind to another receptor (p75(NTR)), which belongs to the tumor necrosis factor superfamily. Hence, nerve growth factor (NGF) and related trophic factors are unique in that two separate receptor types are utilized. Although the biological function of p75(NTR) has been elusive, it has been suggested to mediate apoptosis of developing neurons in the absence of Trk receptors. This presents a tantalizing paradigm, in which life-death decisions of cells are dependent upon the expression and action of two different receptors with distinctive signaling mechanisms. In the presence of TrkA receptors, p75 can participate in the formation of high affinity binding sites and enhanced NGF responsiveness leading to a survival signal. In the absence of TrkA receptors, p75 can generate, in only specific cell populations, a death signal. Here we discuss the unique features and implications of this unusual signal transduction system.
KW - Brain
KW - Central nervous system
KW - Ceramide
KW - Tumor necrosis factor receptors
UR - http://www.scopus.com/inward/record.url?scp=0031823035&partnerID=8YFLogxK
U2 - 10.1038/sj.cdd.4400377
DO - 10.1038/sj.cdd.4400377
M3 - Review article
C2 - 10200484
AN - SCOPUS:0031823035
SN - 1350-9047
VL - 5
SP - 357
EP - 364
JO - Cell Death and Differentiation
JF - Cell Death and Differentiation
IS - 5
ER -