We attempted to isolate genes involved in neuronal differentiation from a cell line 2Y-3t newly established from a mouse cerebellum. 2Y-3t cells proliferate in serum-containing medium and differentiate into neurons in serum-free medium. We took a subtraction method to isolate genes differerentially expressed in differentiated cells and 17 cDNA clones were isolated. Functions of 6 cDNA clones are unknown. No. 60 cDNA clone has 723 nucleotides encoding 240 amino acid residues. It contains two putative EF-hand motifs and a coiled-coil region at C terminal end. Expression of the clone was undetectable at embryonic stage and was increased in brain during development. In situ hybridization showed that the expression was observed predominantly in neurons, suggesting that the protein may play roles in the neuronal differentiation and function. (C) 2002 Elsevier Science (USA). All rights reserved.