title: Ultrastructural analysis of membrane-bound polysomes in mouse "nonsecretory" myeloma (nonproducing type).
abstract: Using our electron microscopic method of polysome analysis we ascertained the numbers of membrane-bound polysomes and their constituent ribosomes in myeloma cells of J 606 (IgG3) and MOPC315 (IgA) parent cell lines and in their variants that did not produce and, accordingly, secrete either H- or L-chains. Both variants had far fewer membrane-bound polysomes than the respective parent lines. The polysome distribution curve drawn for each of these variants showed one peak at 5-6 ribosomes. In contrast to this finding, the distribution curves for the J 606 and MOPC315 parent lines gave two peaks. These observations on mouse myelomas strongly resembled those on human myelomas.
mesh_terms: D000818:Animals; D003593:Cytoplasm / Q000648:ultrastructure; D014644:Genetic Variation; D007136:Immunoglobulins / Q000378:metabolism; D051379:Mice; D009101:Multiple Myeloma / Q000235:genetics / Q000473:pathology*; D010950:Plasma Cells / Q000648:ultrastructure; D011132:Polyribosomes / Q000648:ultrastructure*
chemical_list: D007136:Immunoglobulins