Evolution and divergence of sodium channel genes in vertebrates.

ABSTRACT: Invertebrate species possess one or two Na+ channel genes, yet there are 10 in mammals. When did this explosive growth come about during vertebrate evolution? All mammalian Na+ channel genes reside on four chromosomes. It has been suggested that this came about by multiple duplications of an ancestral chromosome with a single Na+ channel gene followed by tandem duplications of Na+ channel genes on some of these chromosomes. Because a large-scale expansion of the vertebrate genome likely occurred before the divergence of teleosts and tetrapods, we tested this hypothesis by cloning Na+ channel genes in a teleost fish. Using an approach designed to clone all of the Na+ channel genes in a genome, we found six Na+ channel genes. Phylogenetic comparisons show that each teleost gene is orthologou

SUBMITTER: Lopreato GF 

PROVIDER: S-EPMC34712 | biostudies-literature | 2001 Jun

REPOSITORIES: biostudies-literature