Glutamate-dependent transcriptional regulation of the chkbp gene: Signaling mechanims

✍ Scribed by Adán Aguirre; Esther López-Bayghen; Arturo Ortega

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 369 KB
• Volume: 70
• Category: Article
• ISSN: 0360-4012
• DOI: 10.1002/jnr.10394

✦ Synopsis

Abstract

Glutamate, the major excitatory neurotransmitter, induces a signal from the membrane to the nucleus that regulates gene expression. The gene encoding the chick kainate binding protein undergoes a glutamate‐dependent transcriptional regulation via an activator protein‐1 site within its promoter region. To characterize this event, cultured chick Bergmann glia cells were exposed to glutamate, and a dose‐dependent increase in promoter activity was established. The glutamate effect is mediated through Ca^2+^‐permeable α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid/kainate receptors. The signaling cascade includes phosphatidyl inositol 3‐kinase, Ca^2+^/calmodulin‐dependent protein kinase II, mitogen‐activated protein kinase, and p90 ribosomal S6 kinase activation. The cAMP response‐element binding protein becomes phosphorylated and activates fos transcription. Finally, the activator protein‐1 complex binds to the glutamate response element in the chick kainate binding protein promoter region inducing its activity. We propose that the mitogen‐activated protein kinase/p90 ribosomal S6 kinase pathway plays a critical role in glutamate‐induced gene transcription. © 2002 Wiley‐Liss, Inc.