TY - JOUR
T1 - Visualizing muscle cell migration in situ
AU - Knight, Brian
AU - Laukaitis, Christina
AU - Akhtar, Nasreen
AU - Hotchin, Neil A.
AU - Edlund, Magnus
AU - Horwitz, Alan Rick
N1 - Funding Information:
This study was supported by NIH grants GM23244 and GM53905. N.A.H. is supported by an MRC Career Establishment Award (G9803567). We thank Kathy Krull and Marianne Bronner-Fraser for many useful discussions about slice technology. We also thank Marti Ware, Karen Donais and Derek Reubish for their help, and Jon Weiss for comments on the manuscript.
PY - 2000/5/1
Y1 - 2000/5/1
N2 - Background: Cell migration has been studied extensively by manipulating and observing cells bathed in putative chemotactic or chemokinetic agents on planar substrates. This environment differs from that in vivo and, consequently, the cells can behave abnormally. Embryo slices provide an optically accessible system for studying cellular navigation pathways during development. We extended this system to observe the migration of muscle precursors from the somite into the forelimb, their cellular morphology, and the localization of green fluorescent protein (GFP)-tagged adhesion-related molecules under normal and perturbed conditions. Results: Muscle precursors initiated migration synchronously and migrated in broad, rather than highly defined, regions. Bursts of directed migration were followed by periods of meandering or extension and retraction of cell protrusions. Although paxillin did not localize to discernible intracellular structures, we found that α-actinin localized to linear, punctate structures, and the α5 integrin to some focal complexes and/or vesicle-like concentrations. Alterations in the expression of adhesion molecules inhibited migration. The muscle precursors migrating in situ formed unusually large, long-lived protrusions that were polarized in the direction of migration. Unlike wild-type Rac, a constitutively active Rac localized continuously around the cell surface and promoted random protrusive activity and migration. Conclusions: The observation of cellular migration and the dynamics of molecular organization at high temporal and spatial resolution in situ is feasible. Migration from the somite to the wing bud is discontinuous and not highly stereotyped. In situ, local activation of Rac appears to produce large protrusions, which in turn, leads to directed migration. Adhesion can also regulate migration.
AB - Background: Cell migration has been studied extensively by manipulating and observing cells bathed in putative chemotactic or chemokinetic agents on planar substrates. This environment differs from that in vivo and, consequently, the cells can behave abnormally. Embryo slices provide an optically accessible system for studying cellular navigation pathways during development. We extended this system to observe the migration of muscle precursors from the somite into the forelimb, their cellular morphology, and the localization of green fluorescent protein (GFP)-tagged adhesion-related molecules under normal and perturbed conditions. Results: Muscle precursors initiated migration synchronously and migrated in broad, rather than highly defined, regions. Bursts of directed migration were followed by periods of meandering or extension and retraction of cell protrusions. Although paxillin did not localize to discernible intracellular structures, we found that α-actinin localized to linear, punctate structures, and the α5 integrin to some focal complexes and/or vesicle-like concentrations. Alterations in the expression of adhesion molecules inhibited migration. The muscle precursors migrating in situ formed unusually large, long-lived protrusions that were polarized in the direction of migration. Unlike wild-type Rac, a constitutively active Rac localized continuously around the cell surface and promoted random protrusive activity and migration. Conclusions: The observation of cellular migration and the dynamics of molecular organization at high temporal and spatial resolution in situ is feasible. Migration from the somite to the wing bud is discontinuous and not highly stereotyped. In situ, local activation of Rac appears to produce large protrusions, which in turn, leads to directed migration. Adhesion can also regulate migration.
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U2 - 10.1016/S0960-9822(00)00486-3
DO - 10.1016/S0960-9822(00)00486-3
M3 - Article
C2 - 10837222
AN - SCOPUS:0034194623
SN - 0960-9822
VL - 10
SP - 576
EP - 585
JO - Current Biology
JF - Current Biology
IS - 10
ER -