Beyond CREB: The transcription factor (TF) NF-kappa B is activated after perforant pathway in vivo LTP in hilar mossy cells of the mouse hippocampus

R. FREUDENTHAL, A. ROMANO, J. REKART, A. ROUTTENBERG

Orlando, Florida. USA.

Otro; 32st SFN Annual Meeting; 2002

Society for Neuroscience

BEYOND CREB: THE TRANSCRIPTION FACTOR (TF) NF-B IS ACTIVATED AFTER PERFORANT PATHWAY IN VIVO LTP IN HILAR MOSSY CELLS OF THE MOUSE HIPPOCAMPUS R. Freudenthal2; A. Romano2; J. Rekart1; A. Routtenberg1* 1. Psychology, Northwestern University, Evanston, IL, USA 2. Neurobiologica, Universidad de Buenos Aires, Buenos Aires, Argentina Distinct molecular processes underlie different temporal phases of hippocampal LTP. Late phases of LTP recruit gene transcription and protein synthesis. The current focus on CREB has led to the misunderstanding that it alone regulates transcription. To the contrary, TFs work in a combinatorial fashion. The present report demonstrates the participation of another TF: NF-B. NF-B, a heterodimer composed of p65 and p50 monomers, is usually present in the cytoplasm complexed to an inhibitory protein (IB). Phosphorylation releases IB from NF-B, which translocates to the nucleus (Mol Br Res 38:179-90, 1996; Brain Res. 855:274-281, 2000). We show that LTP induction activates NF-B in the mouse hippocampus. Animals were sacrificed 15 min after one of 3 treatments: tetanization (LTP), low frequency stimulation (LFS) or untreated controls (CT). Hippocampal NF-B activity was estimated by electrophoretic mobility shift assays (EMSAs)or by immunohistochemistry of hippocampal sections using an antibody against the activated form of p65. EMSAs showed higher levels of hippocampal NF-B activity in the LTP group than in either the LFS or CT groups. We observed cytoplasmic-to-nuclear translocation of activated NF-B in hilar mossy cells of the LTP group and increased immunoreactivity in CA3 and dentate gyrus granule cells of LTP and LFS groups. These results call attention to NF-Bs role in plasticity, the participation of mossy cells in LTP, and synapse-to-nucleus signaling of NF-B.Supported by: NSF IBN-0090723 to AR Citation:R. Freudenthal, A. Romano, J. Rekart, A. Routtenberg. BEYOND CREB: THE TRANSCRIPTION FACTOR (TF) NF-B IS ACTIVATED AFTER PERFORANT PATHWAY IN VIVO LTP IN HILAR MOSSY CELLS OF THE MOUSE HIPPOCAMPUS Program No. 143.8. 2002 Abstract Viewer/Itinerary Planner. Washington, DC: Society for Neuroscience, 2002. Online.