BDNF GENE CAN BE ACTIVATED BY CA2-NOVO AP-1 SYNTHESIS( SIGNALS WITHOUT INVOLVEMENT OF DE)

Although stimulation of N-methyl-D-aspartate receptors or voltage-depe ndent calcium channels induces both the activation of c-fos and brain- derived neurotrophic factor (BDNF) genes, it is not certain how the ac tivation of these genes is related. Using primary cultures of rat hipp ocampal neurons, we found that exposing the cells to cycloheximide all owed subsequent activation of BDNF mRNA expression, although activatio n of AP-1 DNA-binding activity resulting from c-fos induction was abol ished. Super-induction of BDNF gene was also caused by cycloheximide. The estimate half-life of BDNF mRNA was approximately 2.5 hrs, which w as almost identical to that of c-fos mRNA. These results indicate that nascent AP-1 is not required for the activation of BDNF gene, leading to the notion that the BDNF ene can be activated by Ca2+ signals as a n immediate early gene. (C) Academic Press