title: The role of caldesmon in the regulation of receptor capping in mouse T-lymphoma cell.
abstract: Several complementary techniques, including immunocytochemical and immunobiochemical analyses, two-dimensional gel electrophoresis, and peptide mapping, were used in this study to examine the involvement of caldesmon in lymphocyte receptor capping. We have found a lymphoma 140-kDa polypeptide that is structurally similar to muscle caldesmon, suggesting that this polypeptide may be a lymphoma caldesmon. When lymphoma 140-kDa polypeptide is extracted from permeabilized cells using 25 mM MgCl2, capping is inhibited. Adding the 140-kDa protein or gizzard caldesmon back to the extracted cells restores their ability to cap. These findings suggest that actin-linked regulatory proteins such as caldesmon may be critically important to actomyosin-mediated contraction which, in turn, is responsible for collecting receptors into cap structures.
authors.affiliation: Department of Anatomy and Cell Biology, University of Miami, Florida 33101.
authors.forename: G
authors.initials: G
authors.lastname: Walker
authors.forename: W G
authors.initials: WG
authors.lastname: Kerrick
authors.forename: L Y
authors.initials: LY
authors.lastname: Bourguignon
mesh_terms: D000818:Animals; D002148:Calmodulin-Binding Proteins / Q000302:isolation & purification / Q000502:physiology*; D002460:Cell Line; D002462:Cell Membrane / Q000276:immunology; D002645:Chickens; D015151:Immunoblotting; D007152:Immunologic Capping; D008223:Lymphoma / Q000276:immunology*; D051379:Mice; D011971:Receptors, Immunologic / Q000502:physiology*
chemical_list: D002148:Calmodulin-Binding Proteins; D011971:Receptors, Immunologic