P0-Cre transgenic mice for inactivation of adhesion molecules in Schwann cells

Normal peripheral nerve myelination depends on Schwann tell-basal Lamina interactions. An important component of Schwann cell basal lamina is laminin-predominantly laminins 2 and 4, Mutations in the alpha 2 chain common to these two isoforms are associated with dysmyelination in mouse (dy) and man (congenital muscular dystrophy). Thus, laminin 2 and 4 receptors are also Likely to be important for myelin formation, Several laminin 2/4 receptors are detected at the basal lamina surface of myelin-forming Schwann cells, namely, alpha 6 beta 4 and alpha 6 beta 1 integrins and dystroglycan. The evidence linking these receptors to myelination is suggestive, but not conclusive, Genetic studies have not Jet confirmed a role for these molecules in myelin formation, Natural or targeted inactivation of alpha 6, beta 4, and beta 1 integrins and of dystroglycan hare profound effects on other tissues causing embryonic or perinatal death before myelination, Therefore, to conditionally inactivate these receptors specifically in myelin-forming Schwann cells, we have constructed and initially characterized a P-0-Cre transgene that activates Cre-mediated recombination of loxP-containing genes in peripheral nerve.