trkC may be an inducible transcription factor target gene.
Mechanical injury to hippocampus by needle insertion induces N-methyl-D-aspartate (NMDA) receptor-dependent expression of neurotrophin receptor mRNAs (trkB, trkC) and inducible transcription factors (ITFs, i.e. Fos, c-Jun, Krox-24) in dentate gyrus neurones. To examine the possibility that de novo synthesis of ITFs was necessary for increased expression of trk mRNA we prevented protein synthesis for 5 h using the protein synthesis inhibitor, cycloheximide (4 x 10 mg kg-1, i.p., 1 h before and 1, 2 and 3 h after injury). Cycloheximide abolished expression of ITFs 4 h after injury. Cycloheximide had no effect on trkB mRNA expression but attenuated the injury-induced increase in trkC mRNA expression in dentate gyrus at 4 h by 75%. These results suggest that trkC may be an ITF target gene in vivo.
Hughes
P
P
Department of Pharmacology, School of Medicine, University of Auckland, New Zealand.
Dragunow
M
M
D000818:Animals; D002529:Cerebellar Nuclei / Q000502:physiology*; D003513:Cycloheximide / Q000494:pharmacology; D015870:Gene Expression; D008297:Male; D011493:Protein Kinase C / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics*; D051381:Rats; D017208:Rats, Wistar; D014157:Transcription Factors / Q000235:genetics*; D014158:Transcription, Genetic
D012333:RNA, Messenger; D014157:Transcription Factors; D003513:Cycloheximide; D011493:Protein Kinase C