Lymphoma Thy-1 glycoprotein is linked to the cytoskeleton via a 4.1-like protein.
In this study we have found that the phosphoprotein doublet of 68,000 and 65,000 daltons (68/65 kD) in mouse T-lymphoma cells shares several structural and functional similarities with erythrocyte band 4.1. Our evidence for identifying the 68/65-kD doublet as a lymphoma 4.1-like protein is as follows: it displays an immunological cross-reactivity with anti-erythrocyte band 4.1 antibody; it exhibits a Svedberg unit of sedimentation coefficient of 4 S; it is phosphorylated in the presence of phorbol ester (phorbol-12-O-tetradecanoylphorbol-13-acetate) and its phosphorylation requires Ca2+; it is phosphorylated primarily at serine residues; and it can bind directly to fodrin (a spectrin-like actin-binding protein). In addition, this lymphoma 4.1-like protein can be both colocalized and coisolated with the major T-lymphocyte-specific glycoprotein, Thy-1 (gp 25). Therefore, all of these results strongly suggest that the lymphoma 4.1-like protein (68/65-kD doublet) may play a pivotal role in linking the Thy-1 (gp 25) glycoprotein to fodrin which, in turn, binds to the actin filaments that are responsible for recruiting Thy-1 antigens into cap structures.
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D000954:Antigens, Surface / Q000032:analysis* / Q000378:metabolism; D001798:Blood Proteins / Q000378:metabolism; D002460:Cell Line; D002462:Cell Membrane / Q000648:ultrastructure; D003598:Cytoskeletal Proteins; D003599:Cytoskeleton / Q000648:ultrastructure*; D005455:Fluorescent Antibody Technique; D008223:Lymphoma / Q000473:pathology*; D008565:Membrane Proteins; D051379:Mice; D008970:Molecular Weight; D009479:Neuropeptides; D011485:Protein Binding; D013049:Spectrin / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D018800:Thy-1 Antigens
D000596:Amino Acids; D000954:Antigens, Surface; D001798:Blood Proteins; D003598:Cytoskeletal Proteins; D008565:Membrane Proteins; D009479:Neuropeptides; D018800:Thy-1 Antigens; C028841:erythrocyte membrane band 4.1 protein; C120557:erythrocyte membrane protein band 4.1-like 1; D013049:Spectrin; D013755:Tetradecanoylphorbol Acetate