Prostaglandin binding does not require direct cell-cell contact during chick myogenesis in vitro.
Myogenic differentiation in vitro involves at least three events at the cell surface: binding of prostaglandin to the cells, contact-mediated cell-cell recognition, and fusion of the myoblast membranes into myotubes. While the earlier events are thought to be necessary for subsequent fusion, the sequence of events has not been determined. A major impediment to determining the initial event has been the lack of synchrony of cell differentiation in vitro. To overcome this, we cultured chick embryo myoblasts as a suspension of single cells in gyratory rotation in medium without added Ca2+. Under these conditions, myoblasts exhibited characteristic prostaglandin binding at 34 h. Within 30 min, the cells began to aggregate. Because this occurred without change of medium or conditions of rotation, we termed the process autoaggregation. Within 8-10 h. cells within these autoaggregates began to fuse into syncytia. These results suggest that an early cell surface event in embryonic myogenesis is the characteristic binding of prostaglandin to the myoblasts. The results demonstrate that this binding precedes any direct cell-cell contact and suggest that it causes the subsequent change in myoblast cell-cell adhesion.
D000527:Alprostadil / Q000378:metabolism; D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002449:Cell Aggregation; D002450:Cell Communication; D002459:Cell Fusion; D002478:Cells, Cultured; D002642:Chick Embryo; D009132:Muscles / Q000166:cytology / Q000196:embryology / Q000502:physiology*; D011982:Receptors, Prostaglandin / Q000378:metabolism*
D011982:Receptors, Prostaglandin; D000527:Alprostadil; D002118:Calcium