Related Experiment Video
Updated: Apr 17, 2026
Analyzing In Vivo Cell Migration using Cell Transplantations and Time-lapse Imaging in Zebrafish Embryos
Published on: April 29, 2016
The TORC2 component, Sin1, controls migration of anterior mesendoderm during zebrafish gastrulation
Julien G Dumortier1, Nicolas B David2
1INSERM U1024, Paris, France; CNRS UMR 8197, Paris, France; IBENS, Institut de Biologie de l'Ecole Normale Supérieure, Paris, France; Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United-Kingdom.
Abstract:
TORC2 is a serine-threonine kinase complex conserved through evolution that recently emerged as a new regulator of actin dynamics and cell migration. However, knockout in mice of its core components Sin1 and Rictor is embryonic lethal, which has limited in vivo analyses. Here, we analysed TORC2 function during early zebrafish development, using a morpholino-mediated loss of function of sin1. Sin1 appears required during gastrulation for migration of the prechordal plate, the anterior most mesoderm. In absence of Sin1, cells migrate both slower and less persistently, which can be correlated to a reduction in actin-rich protrusions and a randomisation of the remaining protrusions. These results demonstrate that, as established in vitro, the TORC2 component Sin1 controls actin dynamics and cell migration in vivo. We furthermore establish that Sin1 is required for protrusion formation downstream of PI3K, and is acting upstream of the GTPase Rac1, since expression of an activated form of Rac1 is sufficient to rescue sin1 loss of function.
Insights
The target of rapamycin complex 2 (TORC2) component Sin1 is crucial for cell migration during zebrafish development. Loss of Sin1 impairs cell movement by affecting actin dynamics and protrusion formation.
Area of Science:
- Cell Biology
- Developmental Biology
- Molecular Biology
Background:
- The serine-threonine kinase complex, TORC2, regulates actin dynamics and cell migration.
- In vivo studies of TORC2 are limited due to embryonic lethality in mice lacking Sin1 or Rictor.
Purpose of the Study:
- To investigate the in vivo function of TORC2 during early zebrafish development.
- To elucidate the role of the TORC2 component Sin1 in cell migration and actin dynamics.
Main Methods:
- Morpholino-mediated knockdown of sin1 in zebrafish embryos.
- Analysis of prechordal plate cell migration during gastrulation.
- Microscopy to assess cell migration, persistence, and actin-rich protrusions.
- Investigated the involvement of PI3K and Rac1 signaling pathways.
Main Results:
- Sin1 is essential for the migration of the anterior mesoderm (prechordal plate) during zebrafish gastrulation.
- Loss of Sin1 leads to reduced cell migration speed and persistence.
- Sin1 deficiency results in fewer actin-rich protrusions and randomizes their orientation.
- Sin1 acts downstream of PI3K and upstream of Rac1 in controlling cell protrusion formation.
Conclusions:
- Sin1, a component of TORC2, is vital for regulating actin dynamics and cell migration in vivo during early development.
- Sin1 is required for proper protrusion formation, acting through the PI3K-Rac1 pathway.
- These findings extend in vitro observations to an in vivo developmental context.
Related Concept Videos
01:56Gastrulation
01:10Zygotic Development And Stem Cell Formation