Characterization of a neuronal kappaB-binding factor distinct from NF-kappaB.
Brain Res Mol Brain Res
; 67(2): 303-15, 1999 Apr 20.
Article
em En
| MEDLINE
| ID: mdl-10216229
ABSTRACT
Transcription factors that bind kappaB enhancer elements have begun to garner wide attention in neurobiology. Data suggest that activation of kappaB-binding factors in neurons can be protective against various neurotoxins, but other data have connected NF-kappaB to cell death. In electrophoretic mobility shift assays of kappaB-binding activity, we have found that the predominant activity in rat brain tissue, in primary neurons, and in neuronal cell lines has a mobility inconsistent with that of bona fide NF-kappaB (RelA-p50 heterodimer). We have tentatively termed this activity neuronal kappaB-binding factor (NKBF). Competition assays with various DNA probes distinguished NKBF from NF-kappaB. Probes that efficiently bind the p50 homodimer were able to compete with a conventional NF-kappaB probe for NKBF binding, but NKBF did not react with antibodies to p50 (or any other known Rel family members). Furthermore, UV-crosslinking indicated that NKBF is composed of two polypeptides of 82 kDa and 27 kDa. Although NKBF activity can be elevated in a manner independent of new macromolecular synthesis, it does not appear to be modulated by IkappaB. Finally, no NF-kappaB was induced by glutamate in highly enriched neuronal cultures, although it was induced in neuron-glia cocultures. These data suggest that the primary kappaB-binding transcription factor in neurons is a novel protein complex distinct from NF-kappaB.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
NF-kappa B
/
Proteínas I-kappa B
/
Proteínas do Tecido Nervoso
/
Neurônios
Limite:
Animals
Idioma:
En
Revista:
Brain Res Mol Brain Res
Assunto da revista:
BIOLOGIA MOLECULAR
/
CEREBRO
Ano de publicação:
1999
Tipo de documento:
Article
País de afiliação:
Estados Unidos