Identification of tubulin-binding proteins of the chicken erythrocyte plasma membrane skeleton which colocalize with the microtubular marginal band
Stetzkowski-Marden, F.; Deprette, C.; Cassoly, R.
European Journal of Cell Biology 54(1): 102-109
1991
ISSN/ISBN: 0171-9335 PMID: 2032540 Document Number: 369553
The plasma membrane of nucleated erythrocytes contains a microtubular marginal band which appears to be associated with the plasma membrane skeleton. In this report, we identify two families of cytoskeletal proteins which may be involved in such an association. These proteins, of molecular mass 78 kDa and 48 kDa on SDS-PAGE, are shown to bind tubulin based on a 125I-labeled tubulin binding assay. Solubilization of isolated chicken erythrocyte plasma membranes in Triton X-100 shows that these proteins centrifuge with the pellet, indicating that they are bound to the membrane skeleton. Finally, immunofluorescence studies using antisera raised against the 78 kDa and 48 kDa proteins show that they colocalize with the marginal band in intact cells. Colocalization of cytoskeletal tubulin-binding proteins with the marginal band favors a hypothesis suggesting that the 78 kDa and 48 kDa proteins are involved in the association of the two molecular superstructures.