The reelin signaling pathway: some recent developments.

Jossin, Yves [UCL] Bar, Isabelle Ignatova, Nina [UCL] Tissir, Fadel [UCL] De Rouvroit, Catherine Lambert Goffinet, André [UCL]

The Reelin signaling pathway plays a key role in the architectonic development of the central nervous system. Extracellular Reelin binds to receptors of the lipoprotein receptor family and induces tyrosine phosphorylation of the adaptor Dab1. In this paper, we discuss three recent developments. First, we show that the central part of Reelin is involved in receptor binding and signal activation as reflected in Dab1 phosphorylation. Second, we examine the genomic organization, alternative splicing and promoter use of the Dab1 gene, which hint at a particularly complex regulation. Third, we present preliminary studies by in situ hybridization that demonstrate regulated expression of Reelin receptors and Dab1 by radial precursors in the ventricular zone.