Activation of TRPV4 channels reduces migration of immortalized neuroendocrine cells.

Calcium is a universal signal, and its capacity to encode intracellular messages via spatial, temporal and amplitude characteristics allows it to participate in most cellular events. In a specific context, calcium plays a pivotal role in migration, although its role has not been elucidated fully. By using immortalized gonadotropin-releasing hormone-secreting neurons (GN11), we have now investigated the role of TRPV4, a member of the vanilloid family of Ca(2+) channels, in neuronal migration. Our results show that TRPV4 channels are present and functional in GN11 cells and their localization is polarized and enriched in lamellipodial structures. TRPV4 activation leads to a retraction of the lamellipodia and to a decrease in migratory behaviour; moreover cells migrate slower and in a more random manner. We therefore provide evidence for a new regulation of gonadotropin-releasing hormone neurons and a new role for calcium at the leading edge of migratory cells.