Erythrocytes structural proteins

If preparative or instrumental artifact is ruled out, the universal occurrence of red-shifted Cotton effects with a-helical character in all the membranes studied points to a common property of the proteins in biological membranes. The ORD results from lipid-free mitochondrial structural protein and erythrocyte ghost protein are consistent with assigning the red shift in these membranes to aggregated protein. It is, therefore, reasonable that similar protein-protein association may occur in all membranes. Ionic requirements for membrane stability could then reflect in part the requirements for protein-protein association. To some extent the molecular associations which stabilize membranes, therefore, may be protein-protein as well as lipid-lipid in nature. 

Chen, Q., Heddini, A., Barragan, A., Fernandez, V., Pearce, S. F., and Wahlgren, M. (2000a). The semiconserved head structure of Plasmodium falciparum erythrocyte membrane protein 1 mediates binding to multiple independent host receptors. J. Exp. Med. 192,1-10. 

The membrane of an erythrocyte comprises intricately linked lipid and protein components. Therefore, liposomes made without structural proteins cannot be fully satisfactory model systems. Nevertheless, a-terthienyl induced photodynamic membrane damage in glucose-containing liposomes, probably through lipid peroxidation 185). The modification of the membrane properties was revealed by leakage of glucose trapped in the liposomes. 

Several studies have shown (cf. review by Bakerman and Wasem-iller, 1967 Engelman et al., 1967 Terry et al., 1967 Engelman and Morowitz, 1968a,b) that membrane dissociation could be limited to the separation of lipoprotein subunits by the use of appropriate agents and conditions. On the other hand, the use of selected solvents has permitted the isolation and study of structural protein. Data from such investigations made with erythrocyte membranes constitute the most complete set available (Bakerman and Wasem-iller, 1967 Zahler, 1968) and for this reason will be used in the following analysis of membrane dissociation mechanism. 

Solvation of Structural Protein from Erythrocyte Membrane ... 

Cartron, J. P., and Rahuel, C., 1992, Human erythrocyte glycophorins Protein and gene structure analysis, Transfus. Med. Rev. 11 63-92. 

The structure of the human erythrocyte glucose transport protein... 

Gowda, A.S.P., Madhunapantula, S.V., Achur, R.N., Valiyaveettil, M., Bhavanandan, V.P., and Gowda, D. C. (2007) Structural basis for the adherence of plasmodium falciparum-infected erythrocytes to chon-droitin 4-sulfate and design of novel photoactivable reagents for the identification of parasite adhesive proteins./. Biol. Chem. 282, 916-928. 

In erythrocytes and most other cells, the major structural link of plasma membranes to the cytoskeleton is mediated by interactions between ankyrin and various integral membrane proteins, including Cf/HCOj antiporters, sodium ion pumps and voltage-dependent sodium ion channels. Ankyrin also binds to the =100 nm, rod-shaped, antiparallel a(3 heterodimers of spectrin and thus secures the cytoskeleton to the plasma membrane. Spectrin dimers self-associate to form tetramers and further to form a polygonal network parallel to the plasma membrane (Fig. 2-9D). Neurons contain both spectrin I, also termed erythroid spectrin, and spectrin II, also termed fodrin. Spectrin II is found throughout neurons, including axons, and binds to microtubules, whereas spectrin I occurs only in the soma and dendrites. 

---