Plasma membrane regulation

Draeger, A., Wray, S., and E.B. Babiychuk, 2005, Domain architecture of die smooth-muscle plasma membrane regulation by annexins. Biochem J. 387(Pt 2) 309—14. 

MEMBRANE TRANSPORT Membrane transport mechanisms are vital to living organisms. Ions and molecules constantly move across cell plasma membranes and across the membranes of organelles. This flux must be carefully regulated to meet each cell s metabolic needs. For example, a cell s plasma membrane regulates the entrance of nutrient molecules and the exit of waste products. Additionally, it regulates intracellular ion concentrations. Because lipid bilayers are generally impenetrable to ions and polar substances, specific transport components must be inserted into cellular membranes. Several examples of these structures, referred to as transport proteins or permeases, are discussed. 

The plasma membrane regulates the traffic of molecules into and out of the cell. 

Glucose transporter of animal cell plasma membrane regulated by Insulin... 

Kessler, J.A., Conn, G. and Hatchers, V.B. (1986) Isolated plasma membranes regulate neurotransmitter expression and facilitate effects of a soluble brain cholinergic factor. Proc. Natl. Acad. Sci. USA 83 3528-3532. 

Rapl up-regulation and activation on plasma membrane regulates T cell adhesion. 

Fulton, D., Babbitt, R., ZoeUner, S., Fontana, J., Acevedo, L., McCabe, TJ., Iwakiri, Y, and Sessa, W.C. (2004). Taigeting of endothehal nitric-oxide synthase to the cytoplasmic face of the Golgi complex or plasma membrane regulates Akt- versus calcium-dependent mechanisms for nitric oxide relea.se. J. Biol. Chem. 279(29) 30349-57. 

Three hormones regulate turnover of calcium in the body (22). 1,25-Dihydroxycholecalciferol is a steroid derivative made by the combined action of the skin, Hver, and kidneys, or furnished by dietary factors with vitamin D activity. The apparent action of this compound is to promote the transcription of genes for proteins that faciUtate transport of calcium and phosphate ions through the plasma membrane. Parathormone (PTH) is a polypeptide hormone secreted by the parathyroid gland, in response to a fall in extracellular Ca(Il). It acts on bones and kidneys in concert with 1,25-dihydroxycholecalciferol to stimulate resorption of bone and reabsorption of calcium from the glomerular filtrate. Calcitonin, the third hormone, is a polypeptide secreted by the thyroid gland in response to a rise in blood Ca(Il) concentration. Its production leads to an increase in bone deposition, increased loss of calcium and phosphate in the urine, and inhibition of the synthesis of 1,25-dihydroxycholecalciferol. 

In addition to intracellular heme-containing proteins, big-conductance calcium-dependent K+ (BKCa) channels and calcium-spark activated transient Kca channels in plasma membrane are also tar geted by CO [3]. As well known, nitric oxide (NO) also activates BKca channels in vascular smooth muscle cells. While both NO and CO open BKCa channels, CO mainly acts on alpha subunit of BKCa channels and NO mainly acts on beta subunit of BKca channels in vascular smooth muscle cells. Rather than a redundant machinery, CO and NO provide a coordinated regulation of BKca channel function by acting on different subunits of the same protein complex. Furthermore, pretreatment of vascular smooth muscle... 

During exocytosis, intracellular vesicles fuse with the plasmalemma. As a consequence, the vesicle components are incoiporated into the plasma membrane and the vesicle content is released into the extracellular space. We distinguish constitutive and regulated exocytosis. 

In addition to secretory cells, many non-secretory cells are capable of regulating exocytotic fusion of transport vesicles that are derived from endosomal precursors. For instance, vesicles enriched in plasma membrane transport proteins are incorporated in a regulated manner in order to alter metabolite fluxes. Examples include the glucose transporter GLUT-4 in muscle and fat tissues, a key element in the control of... 

GPCR function has been shown to be regulated by several different mechanisms. The number of receptors on the plasma membrane may be regulated by transcription, mRNA stability, biosynthetic processing, and protein stability. In addition, the function of receptors in the plasma membrane can be influenced by regulatory phosphorylation and by association with other proteins that determine the subcellular location of receptors relative to other signaling molecules. 

Regulation of NHE3 involves many hormonal and physical mechanisms. Acutely, NHE3 activity is promoted by an increase in intracellular pH and this response is rapid. Furthermore, the increase in activity is proportional to the duration of acidification. Chronic acidification promotes recycling of NHE3 from subapi-cal endosomes to the plasma membrane. 

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