M. Yamada et al., SUSTAINED TYROSINE PHOSPHORYLATION OF P140(TRKA) IN PC12H-R CELLS RESPONDING RAPIDLY TO NGF, Brain research, 661(1-2), 1994, pp. 137-146
The PC12h cell, a subclone of PC12 cells, has considerable activities
of tyrosine hydroxylase (TH) and choline acetyltransferase (ChAT) and
shows an NGF-induced increase in both enzyme activities. The TH activi
ty and its inducibility by NGF in PC12h cells were stably maintained i
n the passage of > 200 generations whereas the ChAT activity was not.
We isolated a new cell line, PC12h-R (originally clone 8), from a long
-term culture of PC12h cells. PC12h-R cells still showed the considera
ble TH activity, but not the ChAT activity, and maintained the inducib
ility of TH activity by NGF. Thus, the responses of PC12h-R cells to N
GF were similar to those of chromaffin cells and sympathetic neurons.
PC12h-R cells were found to extend neurites and differentiate into sym
pathetic neuron-like cells in response to NGF much more rapidly than P
C12h cells. In addition, PC12h-R cells showed sustained NGF-induced ty
rosine phosphorylation of p140(trkA) and several cellular proteins, in
cluding 42-, 44- and 54-kDa proteins, in comparison with PC12h cells.
We suggest that the NGF-induced sustained tyrosine phosphorylation sig
nal in PC12h-R cells may be correlated closely with their rapid NGF-in
duced differentiation into neuron-like cells.