S08-13 Tissue interactions in Drosophila nephrogenesis

intracellular components have been identified in both invertebrate and vertebrate, extracellular regulation that allows the morphogenesis cell mass maintaining the epithelial integrity is largely unknown. Here, we present Nectin2, a cell adhesion molecule belonging to the immunoglobulin family has an essential role in the apical constriction. Nectin2 expression is spatially and temporally regulated and its transcripts are confined to the neural plate in Xenopus neurula embryo. Depletion of Nectin2 by antisense-morpholino oligonucleotide resulted in defects in neural tube closure, while overexpression of Nectin2 in ventral ectoderm caused ectopic apical constriction. Analysis at the cellular level revealed that the cortical actin accumulation was severely affected. Interestingly, we found that the intracellular domain of Nectin2 harboring the binding site for Afadin which links Nectin2 to actin is not essential for the constricting activity. Instead, we found that N-cadherin plays a cooperative role in the apical constriction through the interaction with Nectin2. In this presentation, we will discuss about the new regulatory mechanism for apical constriction by the cell adhesion molecules.