Differential display cloning of a novel rat cDNA (RNB6) that shows high expression in the neonatal brain revealed a member of Ena/VASP family

We have used the differential display method to identify genes that control the neural cell development in CNS. Screening of the differential display bands that showed higher expression at neonate than at adult age enabled us to identify a novel rat cDNA (RNB6) coding for a protein of 393 amino acid residues, Database search revealed this gene as a rat homologue of the murine EVL, a member of Ena/VASP protein family that is implicated to be involved in the control of cell motility through actin filament assembly by their GPS motifs, Although the precise characterization of EVL was not reported, our Northern blot and immunoblot analyses demonstrated that RNB6 expression in the brain gradually increases during embryonic development, reaches maximum at postnatal day 1 and decreases thereafter. Studies of tissue distribution revealed the expression, of RNB6 not only in the brain but also in the spleen, thymus and testis, Histochemical analyses showed that RNB6 protein is mainly expressed in neurons and may be expressed in neural fibers, Our analyses suggest that RNB6 is critically involved in the development of CNS probably through the control of neural cell motility and/or including neuronal fiber extension. (C) 1997 Academic Press.