Dynamics of E-cadherin distribution during collective migration of the posterior lateral line primordium

SAMPEDRO, MARIA FLORENCIA; MIÑO, L. GASTÓN; SIGOT, VALERIA

Encuentro; Xth Meeting of the Latin American Society for Developmental Biology; 2019

E-cadherin (E-cadh) is the main cell-adhesion molecule localized at adherens junctions (AJs). Dynamic remodelling of AJs is crucial at maintaining tissue integrity and coordinating collective cell movements during animal embryogenesis. The posterior lateral line primordium (pLLP) in zebrafish is a powerful model system to study guided migration and epithelial morphogenesis, being amenable to live imaging. By combining high-resolution microscopy in zebrafish embryos expressing E-cadh-GFP and automatic segmentation algorithms in 4D, we implemented a routine to analyze E-cadh distribution in vivo during pLLP migration. At every time point analysed we found a polarized distribution of E-cadh expression along the pLLP, with lower expression in cells at the leading front and at higher levels in cells at the trailing end. During one hour time lapse the total area of the pLLP did not change significantly and the global displacement measured was ~50 µm at 24°C.We proposed that this patterned E-cadh distribution at the front and trailing regions of pLLP may be related to differences in local velocity of the cells within those regions. To test this we are currently working to obtain instantaneous velocity fields from the segmented image sequences by using PIV (Particle Image Velocimetry) analysis, a technique routinely used in fluid dynamics with unexplored potential to understand morphogenetic movements.