The behavior and cytoskeletal system of chick gastrula mesodermal cells on substrata coated with lines of fibronectin

Abstract

In order to investigate the mechanism of the formation of the mesodermal layer during chick gastrulation, we observed the behavior of fragments of mesodermal cells explanted and cultured on substrata coated with parallel lines of fibronectin (FN). We also examined the distribution of F-actin, alpha-actinin, and vinculin in explanted fragments by immunocytochemical methods noting particularly their distribution with respect to FN lines. Explants of mesodermal cells flattened on FN-coated substrata and then became elliptical with the major axis of the ellipse oriented along the FN lines and migrated along them. The peripheral cells of explants extended filopodia and lamellipodia which attached preferentially to FN lines and then contracted, pulling other mesodermal cells in explants along passively. Vinculin and alpha-actinin in peripheral anchoring filopodia and lamellipodia co-localized with the terminations of F-actin bundles and with FN lines, suggesting that the peripheral cells were the moving force for explant translocation. We propose based on these results that in vivo, peripheral cells of invaginated cell mass are guided by the known FN-rich fibrous extracellular matrix on the basal surface of epiblast to move outwards; the rest linked to the peripheral cells are pulled away from the primitive streak to spread in tandem to form the mesodermal layer.

Biophysical mechanisms of cardiac looping

“…5B). These stresses pull precardiac mesoderm through the veins toward the caudal end of the heart, possibly inducing additional influx of cells through active migration along lines of stress-aligned fibronectin (Linask and Lash, 1986;Linask and Lash, 1988a;Linask and Lash, 1988b;Toyoizumi et al, 1991;Trinh and Stainier, 2004).…”

Proteomic Profile ofMabuyasp. (Squamata: Scincidae) Ovary and Placenta During Gestation

“…Highly conserved cytoskeletal proteins such as tubulin (α and β‐5 chain), actin (cytoplasmic and alpha‐skeletal), desmin, adseverin (Ads), and α‐actinin‐3 (actin binding protein) were upregulated in placental tissues during early and mid gestation. In early gestation, this upregulation is related to amniote morphogenetic rearrangements when the zygote is under cleavage and cellular differentiation, for example, upregulation in chicken (Toyoizumi et al., ) and mammalian (Sparn et al., ) gastrulation, principally in reptiles where a bi‐modal strategy of gastrulation (involution and ingression) has been suggested (Stower et al., ).…”

Relationship between the distribution of stress fibers and centrosomes in endothelial cells of the rat aorta

“…It has been previously shown that cells can move passively as a result of their attachment to actively migrating cells. In explants of cultured chick embryo gastrula mesoderm motile activity appears to be confined to a subgroup of cells with stress fibers that pull cells, without stress fibers, passively along [Toyoizumi et al, 1991]. During morphogenesis and wound healing, migrating mesenchymal and epidermal cell sheets also appear to contain both actively and passively migrating cells [Trinkaus, 1976[Trinkaus, , 1982.…”