Rat Stromal cell Derived factor 1α ELISA Kit

Collective cell migration plays an important role in development. Here, we study the posterior lateral line primordium (PLLP) a group of about 100 cells, destined to form sensory structures, that migrates from head to tail in the zebrafish embryo. We model mutually inhibitory FGF-Wnt signalling network in the PLLP and link tissue subdivision (Wnt receptor and FGF receptor activity domains) to receptor-ligand parameters. We then use a 3D cell-based simulation with realistic cell-cell adhesion, interaction forces, and chemotaxis. Our model is able to reproduce experimentally observed motility with leading cells migrating up a gradient of CXCL12a, and trailing (FGF receptor active) cells moving actively by chemotaxis towards FGF ligand secreted by the leading cells. The 3D simulation framework, combined with experiments, allows an investigation of the role of cell division, chemotaxis, adhesion, and other parameters on the shape and speed of the PLLP. The 3D model demonstrates reasonable behaviour of control as well as mutant phenotypes.

Collective cell migration is critical for normal development, tissue repair and cancer metastasis. Migration of the posterior lateral line primordium (pLLP) generates the zebrafish sensory organs (neuromasts, NMs). This migration is promoted by the leader cells at the leading edge of the pLLP, which express the G protein-coupled chemokine receptor Cxcr4b and respond to the chemokine Cxcl12a. However, the mechanism by which Cxcl12a/Cxcr4b signaling regulates pLLP migration remains unclear. Here we report that signal transduction by the heterotrimeric G protein subunit G beta 1 is essential for proper pLLP migration. Although both G beta 1 and G beta 4 are expressed in the pLLP and NMs, depletion of G beta 1 but not G beta 4 resulted in an arrest of pLLP migration. In embryos deficient for G beta 1, the pLLP cells migrated in an uncoordinated fashion and were unable to extend protrusions at the leading front, phenocopying those in embryos deficient for Cxcl12a or Cxcr4b. A transplantation assay showed that, like Cxcr4b, G beta 1 is required only in the leader cells of the pLLP. Analysis of F-actin dynamics in the pLLP revealed that whereas wild-type leader cells display extensive actin polymerization in the direction of pLLP migration, counterparts defective for GO, Cxcr4b or Cxcl12a do not. Finally, synergy experiments revealed that G beta 1 and Cxcr4b interact genetically in regulating pLLP migration. Collectively, our data indicate that G beta 1 controls migration of the pLLP, likely by acting downstream of the Cxcl12a/Cxcr4b signaling. This study also provides compelling evidence for functional specificity among G beta isoforms in vivo. (C) 2013 Elsevier Inc. All rights reserved.