Plasma membrane Nature

M.S. Bretscher, M.C. Raff, Mammalian Plasma Membrane , Nature, 258,43 (1975) S.J. Singer, G.L. Nicolson, Fluid Mosaic Model of Structiue of Cell Membranes , Science, 175,720 (1972)... 

Fhill sDR, Jenkins CSP, Luscher EF, Larrieu M-J Molecular differences of exposed surface proteins on thrombasthenic platelet plasma membranes. Nature 257 599-600,1975. 

Kraft, A.S., and Anderson, W.B. (1983) Phorbol Esters Increase the Amount of Ca +, Phospholipid-Dependent Protein Kinase Associated with the Plasma Membrane, Nature 301, 621-623. 

Hunter, T., Ling, N., and Cooper, J. A. (1984) Protein kinase C phosphorylation of the EGF receptor at a threonine residue close to the cytoplasmic face of the plasma membrane. Nature (London) 311, 480-483. 

Rapoport, T.A., 2007. Protein translocation across the eukaryotic endoplasmic reticulum and bacterial plasma membranes. Nature, 450, 663-669. 

Biochemically, most quaternary ammonium compounds function as receptor-specific mediators. Because of their hydrophilic nature, small molecule quaternaries caimot penetrate the alkyl region of bdayer membranes and must activate receptors located at the cell surface. Quaternary ammonium compounds also function biochemically as messengers, which are generated at the inner surface of a plasma membrane or in a cytoplasm in response to a signal. They may also be transferred through the membrane by an active transport system. 

Primarily using isolated plasma membrane vesicles as an experimental preparation, the functional properties of Na /H exchangers have been elucidated. The important kinetic properties include (1) stoichiometry (one-for-one) (2) reversibility (3) substrate specificity (monovalent cations Na, H, Li, NH4, but not K, Rb, Cs, choline) (4) modes of operation (Na -for-H, Na -for-Na Li " -for-Na, Na -for-NH4 ) (5) existence of an internal site for allosteric activation by (6) reversible inhibition by amiloride (Af-amidino-5-amino-6-chloropyr-azine carboxamide) and its 5-amino-substituted analogs and (7) competitive nature... 

Figure 4.2 Hypothetical plasma membrane (PM)-associated structure of FR02. Four histidine residues (white spots) predicted to coordinate two intramembraneous haem groups (white bars) are indicated, as are the tetrapeptide binding sites for FAD and N AD(P)H. The sites of mutations in the FRO gene are indicated (frdl-l,frdl-3) i, inside cell o, outside cell. Reprinted with permission from Nature (Robinson et al., 1999). Copyright (1999) Macmillan Magazines Limited.

The plasma membrane Ca2+-ATPase pump effects outward transport of Ca2+ against a large electrochemical gradient for Ca2+. The mechanism of the pump involves its phosphorylation by ATP and the formation of a high-energy intermediate. This basic mechanism is similar for both the plasma membrane and ER pumps however, the structures of these distinct gene products are substantially different. As discussed below, the ER pump, sometimes called a sarcoendoplasmic reticulum Ca2+-ATPase (SERCA) pump, is inhibited potently by certain natural and synthetic toxins that do not affect the plasma membrane pump. The plasma membrane pump, but not the SERCA pump, is controlled in part by Ca2+ calmodulin, allowing for rapid activation when cytoplasmic Ca2+ rises. 

Fesenko, E., Kolesnikov, S. S. and Lyubarsky, A. L. Induction by cyclic GMP of cationic conductance in plasma membrane of retinal rod outer segment. Nature 313 310-313,1985. 

The oft-touted argument against a physiological role for HbSNO is that even if it does form in RBCs, the Hb-bound NO has to make quite a journey to get to smooth muscle cells it must first cross the RBC plasma membrane, then the RBC free zone (Liao et al., 1999), then cross the endothelial cell membranes twice and finally go through the smooth muscle membrane. Why would nature adopt such a convoluted route when the endothelial cells next to the smooth muscle cells are producing membrane-diffusable NO ... 

Keenan (68) thoroughly discuss the nature of these vesicular and transitional membrane forms. In particular, these well-established, investigators evaluate er to Golgi apparatus transfer, Golgi apparatus to plasma membrane transfer, as well as models for conveying materials through... 

The behaviour of natural ligands has been discussed in Section 4.3.3. In addition to the direct effect of complexation that is related to a decrease in the free ion activity, it has been shown that some ligands, in particular the HS, can be sorbed directly to biological surfaces, in the presence or absence of the trace metal [228,229]. This result is likely due to the fact that HS and similar macromolecules contain hydrophobic moieties that facilitate their adsorption to the plasma membrane and cell wall [157,230,231]. Because adsorption is expected to occur primarily with sites that are independent of the transporters,... 

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