Tropomyosin modulates erythrocyte membrane stability Export

@article{citeulike:6045238, abstract = {The ternary complex of spectrin, actin, and 4.1R (human erythrocyte protein 4.1) defines the nodes of the erythrocyte membrane skeletal network and is inseparable from membrane stability under mechanical stress. These junctions also contain tropomyosin (TM) and the other actin-binding proteins, adducin, protein 4.9, tropomodulin, and a small proportion of capZ, the functions of which are poorly defined. Here, we have examined the consequences of selective elimination of TM from the membrane. We have shown that the mechanical stability of the membranes of resealed ghosts devoid of TM is grossly, but reversibly, impaired. That the decreased membrane stability of TM-depleted membranes is the result of destabilization of the ternary complex of the network junctions is demonstrated by the strongly facilitated entry into the junctions in situ of a {beta}-spectrin peptide, containing the actin- and 4.1R-binding sites, after extraction of the TM. The stabilizing effect of TM is highly specific, in that it is only the endogenous isotype, and not the slightly longer muscle TM that can bind to the depleted membranes and restore their mechanical stability. These findings have enabled us identify a function for TM in elevating the mechanical stability of erythrocyte membranes by stabilizing the spectrin-actin-4.1R junctional complex. 10.1182/blood-2006-07-036954}, author = {An, Xiuli and Salomao, Marcela and Guo, Xinhua and Gratzer, Walter and Mohandas, Narla}, citeulike-article-id = {6045238}, citeulike-linkout-0 = {http://dx.doi.org/10.1182/blood-2006-07-036954}, citeulike-linkout-1 = {http://bloodjournal.hematologylibrary.org/content/109/3/1284.abstract}, citeulike-linkout-2 = {http://bloodjournal.hematologylibrary.org/content/109/3/1284.full.pdf}, citeulike-linkout-3 = {http://view.ncbi.nlm.nih.gov/pubmed/17008534}, citeulike-linkout-4 = {http://www.hubmed.org/display.cgi?uids=17008534}, day = {1}, doi = {10.1182/blood-2006-07-036954}, journal = {Blood}, keywords = {biological, biology, cell, erythrocyte, essay, membrane}, month = {February}, number = {3}, pages = {1284--1288}, posted-at = {2009-10-30 22:43:31}, priority = {2}, title = {Tropomyosin modulates erythrocyte membrane stability}, url = {http://dx.doi.org/10.1182/blood-2006-07-036954}, volume = {109}, year = {2007} }

TY - JOUR ID - citeulike:6045238 L3 - citeulike-article-id:6045238 N2 - The ternary complex of spectrin, actin, and 4.1R (human erythrocyte protein 4.1) defines the nodes of the erythrocyte membrane skeletal network and is inseparable from membrane stability under mechanical stress. These junctions also contain tropomyosin (TM) and the other actin-binding proteins, adducin, protein 4.9, tropomodulin, and a small proportion of capZ, the functions of which are poorly defined. Here, we have examined the consequences of selective elimination of TM from the membrane. We have shown that the mechanical stability of the membranes of resealed ghosts devoid of TM is grossly, but reversibly, impaired. That the decreased membrane stability of TM-depleted membranes is the result of destabilization of the ternary complex of the network junctions is demonstrated by the strongly facilitated entry into the junctions in situ of a {beta}-spectrin peptide, containing the actin- and 4.1R-binding sites, after extraction of the TM. The stabilizing effect of TM is highly specific, in that it is only the endogenous isotype, and not the slightly longer muscle TM that can bind to the depleted membranes and restore their mechanical stability. These findings have enabled us identify a function for TM in elevating the mechanical stability of erythrocyte membranes by stabilizing the spectrin-actin-4.1R junctional complex. 10.1182/blood-2006-07-036954 IS - 3 JF - Blood EP - 1288 TI - Tropomyosin modulates erythrocyte membrane stability VL - 109 SP - 1284 KW - biological KW - biology KW - cell KW - erythrocyte KW - essay KW - membrane AU - An, Xiuli AU - Salomao, Marcela AU - Guo, Xinhua AU - Gratzer, Walter AU - Mohandas, Narla PY - 2007/02/01/ UR - http://dx.doi.org/10.1182/blood-2006-07-036954 ER -