Two neural-cell adhesion molecule(NCAM)-encoding genes in Xenopus laevis are expressed during development and in adult tissues

Expression of genes encoding neural-cell adhesion molecules (NCAM) is regulated to a large extent at the level of alternative splicing. Xenopus laevis contains two functional copies of the NCAM gene and comparison of the amino acid sequences of NCAM proteins derived from both genes shows that they differ at approximately 8% of positions. Differential expression of these proteins during development or in adult tissues could provide an additional level of regulation above that obtained by alternative splicing. PCR analysis however, shows that both NCAM genes are expressed at similar levels throughout embryonic development and in all adult tissues examined.