Gangliosides are sialic acid-containing glycosphingolipids present on mam-malian plasma membranes, where they participate in cell-surface events
such as modulation of growth factor receptors and cell-to-cell and cell-to-matrix interactions. Antibodies to gangliosides have been associated with
a wide range of clinically identifiable acute and chronic neuropathy syn-dromes.
We analyzed the role of gangliosides in the association of the ErbB2 recep-tor tyrosine-kinase (RTK) with lipid rafts in mammary epithelial HC11
cells. Scanning confocal microscopy experiments revealed a strict ErbB2–
GM3 colocalization in wild-type cells. In addition, analysis of membrane
fractions obtained using a linear sucrose gradient showed that ErbB2, epi-
The botulinum neurotoxins (BoNTs) are the most potent protein toxins for
humans. There are seven serotypes of BoNTs (A–G), based on a lack of
cross-antiserum neutralization. The BoNT⁄C and BoNT⁄D serotypes
include mosaic toxins that are organized as D–C and C–D toxins.
Gangliosides are glycosphingolipids mainly present at the outer leaflet of
the plasma membrane of eukaryotic cells, where they participate in recogni-tion and signalling activities. The synthesis of gangliosides is carried out in
the lumen of the Golgi apparatus by a complex system of glycosyltrans-ferases.
The GM2-activator protein (GM2AP) is an essential
cofactor for the degradation of ganglioside GM2 by lyso-somal b-hexosaminidase A. It mediates the interaction
between the water-soluble exohydrolase and its membrane-bound substrate at the lipid–water interphase. Inherited
defects in the gene encoding this glycoprotein result ina fatal
neurological storage disorder, the AB variant of GM2-gangliosidosis. To elucidate the mode of action of this gly-coprotein cofactor, we synthesized the two photoaffinity
-TPD-GM2 and [
Gangliosideshavebeen found toreside inglycosphingolipid-enriched microdomains (GEM) of the plasma membrane
and to be involved in the regulation of epidermal growth
factor receptor (EGFr or ErbB1) activity.To gain further
insight into the mechanisms involved in EGFr modulation
by gangliosides, we investigated the distribution of EGFr
family members in the plasma membrane of CHO-K1 cells,
which were genetically modified to express different gan-glioside molecules or depleted of glycolipids.
Numerous virus–target cell interactions have been described, and it is now clear that different viruses can use similar host-cell receptors for entry. The list of certain and likely host receptors for viral pathogens is long. Among the host membrane components that can serve as receptors for viruses are sialic acids, gangliosides, glycosaminoglycans, integrins and other members of the immunoglobulin superfamily, histocompatibility antigens, and regulators and receptors for complement components.
The GM2-activator protein (GM2AP) is an essential cofactor for the lyso-somal degradation of ganglioside GM2 by b-hexosaminidase A (HexA). It
mediates the interaction between the water-soluble exohydrolase and its
membrane-embedded glycolipid substrate at the lipid–water interface.
Functional deficiencies in this protein result in a fatal neurological storage
disorder, the AB variant of GM2 gangliosidosis.
We have investigated the conformational changes of New-castle disease virus (NDV) glycoproteins in response to
receptor binding, using 1,1-bis(4-anilino)naphthalene-5,5-disulfonic acid (bis-ANS) as a hydrophobicity-sensitive
probe. Temperature- and pH-dependent conformational
changes were detected in the presence of free bovine gan-gliosides. The fluorescence of bis-ANS was maximal at
Prosaposin is a neurotrophic factor that has been demonstrated to mediate
trophic signalling events in different cell types; it distributes to surface
membranes of neural cells and also exists as a secreted protein in different
body fluids. Prosaposin was demonstrated to form tightly bound complexes
with a variety of gangliosides, and a functional role has been suggested for
Campylobacter jejuniinfections are one of the leading causes
of human gastroenteritis and are suspected of being a pre-cursor to Guillain–Barre´ and Miller–Fisher syndromes.
Recently, the complete genome sequence ofC. jejuniNCTC
11168wasdescribed. In this study, themolecular structureof
the lipooligosaccharide and capsular polysaccharide of
C. jejuniNCTC 11168 was investigated. The lipooligosac-charide was shown to exhibit carbohydrate structures anal-ogous to the GM1a and GM2 carbohydrate epitopes of
human gangliosides (shown below)...