Identification and cataloging of genes induced by long-lasting long-term potentiation in awake rats.
Maintenance of long-term potentiation (LTP) requires de novo gene expression. Here we report the direct isolation, using PCR-differential display, of genes whose expression level was altered after induction of long-lasting LTP in the hippocampus of freely moving awake rats. Differential display using 480 primer combinations revealed 17 cDNA bands that showed a reproducible change in expression level. These cDNAs represented at least 10 different genes (termed RM1-10), all of which showed up-regulation at 75 min after LTP induction and a return to basal expression levels within 24 h. Three of these genes were known only from expressed sequence tags (RM1-3), two were known genes whose up-regulation by LTP has not been described (GADD153/CHOP and ler5), and five were known genes whose up-regulation by LTP has already been reported (MAPK phosphatase, NGFI-A/zif268, vesl-1S/homer-1a, Ag2, and krox-20). We characterized the expression profiles of genes in the two former categories with respect to NMDA receptor dependency, tissue specificity, and developmental regulation using northern blotting and semiquantitative RT-PCR. The up-regulation of all five of these genes was NMDA receptor-dependent and correlated with the persistence of LTP, suggesting that these genes may play functional roles in prolonged LTP maintenance.
Matsuo
R
R
Mitsubishi Kasei Institute of Life Sciences, Tokyo, Japan. Institute of Medical Sciences, University of Tokyo, Japan.
Murayama
A
A
Saitoh
Y
Y
Sakaki
Y
Y
Inokuchi
K
K
D000818:Animals; D015152:Blotting, Northern; D001923:Brain Chemistry / Q000235:genetics*; D003001:Cloning, Molecular; D017931:DNA Primers; D018076:DNA, Complementary; D004567:Electrodes, Implanted; D018507:Gene Expression Regulation, Developmental; D005820:Genetic Testing / Q000379:methods; D017774:Long-Term Potentiation / Q000235:genetics*; D008297:Male; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000235:genetics; D009473:Neuronal Plasticity / Q000235:genetics; D016133:Polymerase Chain Reaction / Q000379:methods; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000235:genetics*; D014781:Viscera / Q000737:chemistry; D014851:Wakefulness / Q000235:genetics*
D017931:DNA Primers; D018076:DNA, Complementary; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D016194:Receptors, N-Methyl-D-Aspartate