Degradation of c-Fos protein expressed by N-methyl-D-aspartic acid in nuclear fractions of murine hippocampus

Citation
T. Manabe et al., Degradation of c-Fos protein expressed by N-methyl-D-aspartic acid in nuclear fractions of murine hippocampus, BRAIN RES, 905(1-2), 2001, pp. 34-43
Citations number
31
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Neurosciences & Behavoir
Journal title
BRAIN RESEARCH
ISSN journal
0006-8993 → ACNP
Volume
905
Issue
1-2
Year of publication
2001
Pages
34 - 43
Database
ISI
SICI code
0006-8993(20010629)905:1-2<34:DOCPEB>2.0.ZU;2-G
Abstract
In both nuclear and cytosolic fractions of murine hippocampus, constitutive expression was seen with Fra-2 protein, but not with other Fos family memb ers tested including c-Fos, Fos-B and Fra-1 proteins. Fos-B protein was onl y detected in nuclear fractions. The systemic administration of N-methyl-D- aspartic acid (NMDA) induced marked and transient expression of c-Fos prote in, but not other family members. in both hippocampal fractions 2 h later. In vitro incubation at 30 degreesC led to more rapid degradation of inducib le c-Fos protein than constitutive Fra-2 protein in nuclear fractions obtai ned 2 h after the administration of NMDA, without significantly affecting t hat of both member proteins in cytosolic fractions. The addition of phospha tase inhibitors significantly delayed the initial degradation rate of induc ible c-Fos protein, with concomitant facilitation of that of constitutive F ra-2 protein, in nuclear fractions. The addition of protease inhibitors als o delayed the initial degradation of constitutive Fra-2 protein, without ma rkedly altering that of inducible c-Fos protein, in nuclear fractions. Immu noprecipitation analysis revealed that NMDA induced phosphorylation of c-Fo s protein on tyrosine residues in nuclear fractions to a lesser extent than that on serine residues 2 h after administration. These results suggest th at NMDA signals may be propagated to the nucleus to induce both expression and degradation of c-Fos protein through a molecular mechanism associated w ith phosphorylation on serine and/or tyrosine residues in murine hippocampu s. (C) 2001 Elsevier Science B.V. All rights reserved.