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 co ntrol the neural cell development in CNS. Screening of the differentia l display bands that showed higher expression at neonate than at adult age enabled us to identify a novel rat cDNA (RNB6) coding for a prote in 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 thro ugh actin filament assembly by their GPS motifs, Although the precise characterization of EVL was not reported, our Northern blot and immuno blot 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 reveale d the expression, of RNB6 not only in the brain but also in the spleen , thymus and testis, Histochemical analyses showed that RNB6 protein i s mainly expressed in neurons and may be expressed in neural fibers, O ur analyses suggest that RNB6 is critically involved in the developmen t of CNS probably through the control of neural cell motility and/or i ncluding neuronal fiber extension. (C) 1997 Academic Press.