BRAIN-DERIVED NEUROTROPHIC FACTOR INDUCES A RAPID UP-REGULATION OF SYNAPTOPHYSIN AND TAU-PROTEINS VIA THE NEUROTROPHIN RECEPTOR TRKB IN RATCEREBELLAR GRANULE CELLS
Et. Coffey et al., BRAIN-DERIVED NEUROTROPHIC FACTOR INDUCES A RAPID UP-REGULATION OF SYNAPTOPHYSIN AND TAU-PROTEINS VIA THE NEUROTROPHIN RECEPTOR TRKB IN RATCEREBELLAR GRANULE CELLS, Neuroscience letters, 227(3), 1997, pp. 177-180
We have examined the effects of neurotrophins brain derived neurotroph
ic factor (BDNF) and nerve growth factor (NGF) on the expression of th
e maturation-specific proteins synaptophysin end tau, and the growth-a
ssociated protein (GAP)-43 in cerebellar granule cells. We find that B
DNF but not NGF rapidly (within 2 h) upregulates levels of synaptophys
in, tau and c-Fos correlating with expression of the neurotrophin rece
ptor TrkB. The rapid increase in synaptophysin is not preceded by c-Fo
s elevation suggesting a post-transcriptional mechanism may be involve
d. In contrast, no upregulation of GAP-43 levels are seen within this
time period. Phorbol ester mimics the effects of BDNF, indicating that
protein kinase C (PKC) is either a component of, or feeds into the si
gnalling mechanism. We conclude that BDNF, characterized to be surviva
l promoting early in differentiation of cerebellar granule cells, enha
nces maturation at a later stage. (C) 1997 Elsevier Science Ireland Lt
d.