title: Impaired extinction of learned contextual fear memory in early growth response 1 knockout mice.
abstract: Inductive expression of early growth response 1 (Egr-1) in neurons is associated with many forms of neuronal activity. However, only a few Egr-1 target genes are known in the brain. The results of this study demonstrate that Egr-1 knockout (KO) mice display impaired contextual extinction learning and normal fear acquisition relative to wild-type (WT) control animals. Genome-wide microarray experiments revealed 368 differentially expressed genes in the hippocampus of Egr-1 WT exposed to different phases of a fear conditioning paradigm compared to gene expression profiles in the hippocampus of KO mice. Some of genes, such as serotonin receptor 2C (Htr2c), neuropeptide B (Npb), neuronal PAS domain protein 4 (Npas4), NPY receptor Y1 (Npy1r), fatty acid binding protein 7 (Fabp7), and neuropeptide Y (Npy) are known to regulate processing of fearful memories, and promoter analyses demonstrated that several of these genes contained Egr-1 binding sites. This study provides a useful list of potential Egr-1 target genes which may be regulated during fear memory processing.
authors.affiliation: Department of Anatomy and Neuroscience, College of Medicine, Korea University, Seoul 136-705, Korea.
authors.forename: Seungrie
authors.initials: S
authors.lastname: Han
authors.forename: Soontaek
authors.initials: S
authors.lastname: Hong
authors.forename: Jiwon
authors.initials: J
authors.lastname: Mo
authors.forename: Dongmin
authors.initials: D
authors.lastname: Lee
authors.forename: Eunju
authors.initials: E
authors.lastname: Choi
authors.forename: June-seek
authors.initials: JS
authors.lastname: Choi
authors.forename: Woong
authors.initials: W
authors.lastname: Sun
authors.forename: Hyun Woo
authors.initials: HW
authors.lastname: Lee
authors.forename: Hyun
authors.initials: H
authors.lastname: Kim
mesh_terms: D000818:Animals; D003213:Conditioning, Psychological; D051766:Early Growth Response Protein 1 / Q000235:genetics*; D005108:Extinction, Psychological; D005239:Fear; D063990:Gene Ontology; D008297:Male; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D058977:Molecular Sequence Annotation; D020411:Oligonucleotide Array Sequence Analysis; D011401:Promoter Regions, Genetic; D059467:Transcriptome
chemical_list: D051766:Early Growth Response Protein 1; C486109:Egr1 protein, mouse