Article

Cell movement patterns during gastrulation in the chick are controlled by positive and negative chemotaxis mediated by FGF4 and FGF8.

Division of Cell and Developmental Biology, Wellcome Trust Biocentre, University of Dundee, Dundee DD1 5EH, Scotland, United Kingdom.
Developmental Cell (impact factor: 14.03). 10/2002; 3(3):425-37. pp.425-37
Source: PubMed

ABSTRACT During gastrulation in amniotes, epiblast cells ingress through the primitive streak and migrate away to form endodermal, mesodermal, and extraembryonic structures. Here we analyze the detailed movement trajectories of cells emerging at different anterior-posterior positions from the primitive streak, using in vivo imaging of the movement of GFP-tagged streak cells. Cells emerging at different anterior-posterior positions from the streak show characteristic cell migration patterns, in response to guidance signals from neighboring tissues. Streak cells are attracted by sources of FGF4 and repelled by sources of FGF8. The observed movement patterns of anterior streak cells can be explained by an FGF8-mediated chemorepulsion of cells away from the streak followed by chemoattraction toward an FGF4 signal produced by the forming notochord.

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Keywords

anterior streak cells
 
characteristic cell migration patterns
 
detailed movement trajectories
 
different anterior-posterior positions
 
epiblast cells ingress
 
FGF4
 
FGF4 signal
 
FGF8
 
FGF8-mediated chemorepulsion
 
forming notochord
 
GFP-tagged streak cells
 
guidance signals
 
mesodermal
 
observed movement patterns
 
primitive streak
 
streak
 
Streak cells
 
vivo imaging