title: Amino-terminal phosphorylation of c-Jun regulates apoptosis in the retinal ganglion cells by optic nerve transection.
abstract: OBJECTIVE
  To examine the involvement of c-Jun and c-Jun N-terminal phosphorylation (JNP) in apoptosis of retinal ganglion cells (RGCs) after the optic nerve (ON) transection.
  
  
  METHODS
  The expression and phosphorylation of c-Jun protein and apoptosis in RGCs were examined after ON transection in wild-type mice and mice in which both phosphoacceptor serines of Jun have mutated to alanines (c-Jun[AA] mice). The fluorescent tracer 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI) was applied to the superior colliculi (SC), and the right ON was severed after 7 days. After two more weeks, the average number of RGCs per field was calculated.
  
  
  RESULTS
  JNP and TUNEL-labeled apoptotic nuclei were detected in the ganglion cell layer (GCL) of the retina of the wild-type mice in response to ON transection. The numbers of TUNEL-positive nuclei in the c-Jun(AA) mice was reduced in comparison to those in wild-type mice. Retrograde labeling showed that the number of the RGCs in the retinas on the injured side of the c-Jun(AA) mice was significantly higher than in wild-type mice 14 days after the lesion.
  
  
  CONCLUSIONS
  These results suggest that there is a partial but significant contribution of JNP to the induction of apoptosis in RGCs by ON transection.
authors: Laboratory of Gene Regulation and Signal Transduction, Department of Pharmacology, University of California-San Diego, La Jolla, CA, USA. kyoshida@med.hokudai.ac.jp
authors: Kazuhiko
authors: K
authors: Yoshida
authors: Axcel
authors: A
authors: Behrens
authors: Helen
authors: H
authors: Le-Niculescu
authors: Erwin F
authors: EF
authors: Wagner
authors: Takayuki
authors: T
authors: Harada
authors: Junko
authors: J
authors: Imaki
authors: Shigeaki
authors: S
authors: Ohno
authors: Michael
authors: M
authors: Karin
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D002232:Carbocyanines; D002452:Cell Count; D002467:Cell Nucleus; D002470:Cell Survival; D020287:In Situ Nick-End Labeling; D048031:JNK Mitogen-Activated Protein Kinases; D051379:Mice; D008817:Mice, Mutant Strains; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009900:Optic Nerve / Q000378:metabolism; D020221:Optic Nerve Injuries / Q000378:metabolism*; D010766:Phosphorylation; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism*; D012165:Retinal Ganglion Cells / Q000378:metabolism*
chemical_list: C035005:3,3'-dihexadecylindocarbocyanine; D002232:Carbocyanines; D016755:Proto-Oncogene Proteins c-jun; D048031:JNK Mitogen-Activated Protein Kinases; D020928:Mitogen-Activated Protein Kinases