Gangliosides functions

Glycosphingolipids are constituents of the outer leaflet of plasma membranes and are important in cell adhesion and cell recognition. Some are antigens, eg, ABO blood group substances. Certain gangliosides function as receptors for bacterial toxins (eg, for cholera toxin, which subsequently activates adenylyl cyclase). 

Figure 41 Radiolabeled GM2 ganglioside functionalized with an aryl-azide photocross-linker. Photocross-linker is highlighted in red, radiolabeled atom is highlighted by a green circle.

Karlsson, K.A. (1976a) in Ganglioside Function (eds G. Porcellati etal.), Plenum, New York, p. 15. 

CECCARELLI B., APORTI F. FINESSO M. (1976) In ganglioside function biochemical and pharmacological implications, pp. 275-293. Plenum Press, New York and London. 

Markwell MA, Svennerholm L, Paulson JC (1981) Specific gangliosides function as host cell receptors for Sendai vims. Proc Natl Acad Sci U S A 78 5406-5410... 

Gielen, W., 1968, Ganglioside function. Distribution of the serotonin receptor, Z. Naturforsch 23b 117. 

In this context, divalent presentation of this promising candidate has been investigated by the authors using the fixed cone conformation of calix[4]arene to allow introduction of the molecules onto the upper rim, and their projection into the same portion of space, thus mimicking, to some extent, a small portion of the natural cell-surface ganglioside. The synthesis of the divalent neoglycoconjugate was based on initial functionalization of the corresponding diacid with an aminated spacer and further introduction of squaric acid moieties. 

Bullens, R. W., O Hanlon, G. M., Wagner, E. etal. Complex gangliosides at the neuromuscular junction are membrane receptors for autoantibodies and botulinum neurotoxin but redundant for normal synaptic function. /. Neurosci. 22 6876-6884, 2002. 

Yu, R. K. and Ando, S. Structures of some new complex gangliosides. In L. Svennerholm, P. Mandel, H. Dreyfus and P.-F. Urban (eds), Structure and Function of Gangliosides. New York Plenum Press, 1980, pp. 33M5. 

In both of these cases, the ligand (sialic acid) for the analyte of interest (influenza vims) was covalently linked to the PDA backbone generated upon photopolymerization. Functional sensors based on ligands that are noncovalently incorporated into liposomes have also been reported (Charych et al. 1996 Pan and Charych 1997). Mixed liposomes as well as mixed thin films on glass containing a combination of the ganglioside GMl and diacetylene lipids detect the presence of cholera toxin, a protein that binds to GMl. 

Included among drugs that alter the permeability of the membrane are phosphatidylserine, S-adenosylmethionine, and ganglioside extracts. Phosphatidylserine, produced from purified extracts of bovine brain cortex, alters the permeability and functionality of the neuronal membrane. A study... 

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