...-adhesion molecule Neurexin IV. Alternative splicing generates two different Neurexin IV isoforms: Neurexin IV exon3 , which is found in cells that form septate junctions, and Neurexin IV exon4 , which is found in neurons that form no septate junctions. Here, we show that the formation of the BBB depends...

... axons and eventually extend processes into the commissures to wrap individual axon fascicles. Here, we show that this wrapping of axons depends on the interaction of the neuronal transmembrane protein Neurexin IV with the glial Ig-domain protein Wrapper. Although Neurexin IV has been previously...

... and is required for ensheathment of commissural axons. By contrast, Neurexin IV is present on the membranes of neurons and commissural axons, and is highly concentrated at their interfaces with midline glia. Analysis of Neurexin IV and wrapper mutant embryos revealed identical defects in glial migration...

... and its Drosophila homolog, Neurexin IV (NRX IV) are required for the formation of SJs. In this study, we report the genetic, molecular and biochemical characterization of the Drosophila homolog of vertebrate contactin, CONT. Ultrastructural and dye-exclusion analyses of Cont mutant embryos show that CONT...