Effect of age and cognitive status on basal level AP-1 activity in rat hippocampus.
Activator protein-1 (AP-1) was examined at multiple levels (mRNA, DNA binding, composition) in hippocampus of young and aged rats that were behaviorally characterized for spatial memory. GFAP mRNA was measured as a gene product known to increase with aging and to be regulated by AP-1. The activity of Jun-amino terminal-kinase (JNK) was also assessed. Levels of c-jun and c-fos mRNAs were unchanged with aging or spatial learning ability. Abundance of GFAP mRNA was significantly increased in aged hippocampus but did not correlate with spatial learning. Total AP-1 binding activity was unaltered with age or cognitive ability. In hippocampus of young, aged unimpaired and aged impaired rats, AP-1 consists mainly of c-Jun, phosphorylated c-Jun (p-c-Jun), JunD, and smaller amounts of c-Fos. JNK is constitutively active in young and aged hippocampus. We conclude that the basal expression of c-fos and c-jun mRNA, overall AP-1 binding activity and AP-1 composition are not influenced by aging or cognitive ability.
Smith
D R
DR
Department of Psychology, University of North Carolina, Chapel Hill, NC 27599, USA.
Hoyt
E C
EC
Gallagher
M
M
Schwabe
R F
RF
Lund
P K
PK
D000375:Aging / Q000502:physiology*; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D003071:Cognition / Q000502:physiology*; D015870:Gene Expression / Q000502:physiology; D005904:Glial Fibrillary Acidic Protein / Q000235:genetics; D006624:Hippocampus / Q000502:physiology*; D048031:JNK Mitogen-Activated Protein Kinases; D048670:MAP Kinase Kinase 4; D008297:Male; D018782:Maze Learning / Q000502:physiology; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism; D011485:Protein Binding / Q000502:physiology; D016760:Proto-Oncogene Proteins c-fos / Q000235:genetics; D016755:Proto-Oncogene Proteins c-jun / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D020318:Rats, Long-Evans; D013028:Space Perception / Q000502:physiology; D018808:Transcription Factor AP-1 / Q000235:genetics* / Q000378:metabolism*
D005904:Glial Fibrillary Acidic Protein; D016760:Proto-Oncogene Proteins c-fos; D016755:Proto-Oncogene Proteins c-jun; D012333:RNA, Messenger; D018808:Transcription Factor AP-1; D048031:JNK Mitogen-Activated Protein Kinases; D048670:MAP Kinase Kinase 4; D020929:Mitogen-Activated Protein Kinase Kinases