The fine structure of the mid-body of the rat erythroblast.
The development of the mid-body has been studied in mitotic erythroblasts of the rat bone marrow by means of thin sections examined with the electron microscope. A differentiated region on the continuous spindle fibers, consisting of a localized increase in density, is observed at the equatorial plane. The mid-body seems to develop by the aggregation of such denser lengths of spindle fiber. Its appearance precedes that of the cleavage furrow. A plate-like arrangement of fibrillary material lies transversely across the telophase intercellular bridge. Later, this material becomes amorphous and assumes the form of a dense ring closely applied to a ridge in the plasma membrane encircling the middle of the bridge. Although the mid-body forms in association with the spindle fibers, it is a structurally distinct part, and the changes which it undergoes are not shared by the rest of the bundle of continuous fibers.
D000818:Animals; D001853:Bone Marrow / Q000033:anatomy & histology*; D002462:Cell Membrane; D003599:Cytoskeleton; D004583:Electrons; D004900:Erythroblasts; D008853:Microscopy; D008854:Microscopy, Electron; D008938:Mitosis; D051381:Rats
BONE MARROW/anatomy and histology; MICROSCOPY, ELECTRON