LIRF, a gene induced during hippocampal long-term potentiation as an immediate-early gene, encodes a novel RING finger protein

We describe here an LTP-induced gene, LIRF, which encodes a novel protein w ith RING finger and B30.2 domains in its N- and C-terminal portions, respec tively. Each domain is encoded by one exon, suggesting that the organizatio n of the gene was generated by exon shuffling. The amino acid sequences of the mouse, rat, and human LIRF proteins are highly conserved and contain a putative PEST sequence. LIRF is an immediate-early gene in hippocampal gran ule cells, and its expression is upregulated immediately after the inductio n of long-lasting long-term potentiation at perforant pathway-dentate gyrus synapses and returns to the basal level within 150 min. A heterologously e xpressed LIRF protein fused to EGFP localizes specifically to the cytoplasm in COS-7 cells. These findings suggest a possible involvement of LIRF in a limited, early phase of synaptic plasticity. (C) 2001 Elsevier Science.