Post on 19-Jan-2016
Glycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchors
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
ObjectivesObjectivesObjectivesObjectives
Major membrane lipid classes
PLC
GLYCEROLIPID
Glycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchors
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
ObjectivesObjectivesObjectivesObjectives
Most vertebrate glycolipids are Most vertebrate glycolipids are glycosphingolipidsglycosphingolipids
Most vertebrate glycolipids are Most vertebrate glycolipids are glycosphingolipidsglycosphingolipids
Glucosylceramide is a key intermediate in skin Glucosylceramide is a key intermediate in skin barrier formationbarrier formation
Glucosylceramide is a key intermediate in skin Glucosylceramide is a key intermediate in skin barrier formationbarrier formation
Skin water barrier. Formation and secretion of lamellar bodies (LB) at stratum granulosum – stratum corneum Skin water barrier. Formation and secretion of lamellar bodies (LB) at stratum granulosum – stratum corneum interface. Precursor lipids, including glucosylceramide, sphingomyelin, glycerophospholipids, and cholesterol interface. Precursor lipids, including glucosylceramide, sphingomyelin, glycerophospholipids, and cholesterol sulfate, are packaged into LB in the upper epidermis. Fusion of the LB with the apical plasma membrane in the sulfate, are packaged into LB in the upper epidermis. Fusion of the LB with the apical plasma membrane in the uppermost layer of the epidermis (stratum granulosum), allows extrusion of lipid precursors into the extracellular uppermost layer of the epidermis (stratum granulosum), allows extrusion of lipid precursors into the extracellular domain. Enzymatic processing of precursor lipids generates the major lipid classes required for epidermal barrier domain. Enzymatic processing of precursor lipids generates the major lipid classes required for epidermal barrier function.function.
Holleran et al (2006) Febs Letters 23:5456
Normal mouse skinNormal mouse skin
““Gaucher” Gaucher” mouse skin mouse skin
(glucocerebrosidase -/-)(glucocerebrosidase -/-)
Holleran et al (1994) J Clin Invest 93:1756
Glucosylceramide is a key intermediate in skin Glucosylceramide is a key intermediate in skin barrier formationbarrier formation
Glucosylceramide is a key intermediate in skin Glucosylceramide is a key intermediate in skin barrier formationbarrier formation
Normal human skinNormal human skin
Human type 2Human type 2Gaucher disease skin Gaucher disease skin (glucocerebrosidase- (glucocerebrosidase-
deficient)deficient)
Holleran et al (1994) J Clin Invest 93:1756
Glucosylceramide is a key intermediate in skin Glucosylceramide is a key intermediate in skin barrier formationbarrier formation
Glucosylceramide is a key intermediate in skin Glucosylceramide is a key intermediate in skin barrier formationbarrier formation
Glycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchors
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
ObjectivesObjectivesObjectivesObjectives
Glycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchors
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
ObjectivesObjectivesObjectivesObjectives
galactosylceramide and it’s 3-sulfated from, galactosylceramide and it’s 3-sulfated from, sulfatide, are major lipids in the brainsulfatide, are major lipids in the brain
galactosylceramide and it’s 3-sulfated from, galactosylceramide and it’s 3-sulfated from, sulfatide, are major lipids in the brainsulfatide, are major lipids in the brain
Together, GalCer and sulfatide comprise up to 1.9% of brain fresh weight!
galactosylceramide & sulfatide are the major galactosylceramide & sulfatide are the major glycans in the brain, and major lipids in myelinglycans in the brain, and major lipids in myelingalactosylceramide & sulfatide are the major galactosylceramide & sulfatide are the major
glycans in the brain, and major lipids in myelinglycans in the brain, and major lipids in myelin
Myelin total lipids - mole percent
Mo
le r
atio
0
10
20
30
40Phospho-
lipids
Choles-terol
Galacto-lipids
Glycan ratios in the brain
Delcomyn, F. (1998) Foundations of Neurobiology.
W.H. Freeman, New York.
Mutant mice lacking GalCer synthetase (Mutant mice lacking GalCer synthetase (Ugt8aUgt8a) ) oror GalCer 3-sulfotransferase ( GalCer 3-sulfotransferase (Gal3st1) Gal3st1) display myelin display myelin
defects and associated behavioral deficitsdefects and associated behavioral deficits
Mutant mice lacking GalCer synthetase (Mutant mice lacking GalCer synthetase (Ugt8aUgt8a) ) oror GalCer 3-sulfotransferase ( GalCer 3-sulfotransferase (Gal3st1) Gal3st1) display myelin display myelin
defects and associated behavioral deficitsdefects and associated behavioral deficits
Honke et al (2002) PNAS 99:4227
Honke et al (2002) PNAS 99:4227
Popko (2000) Glia 29:149
Glycoglycerolipids are not widely distributed in vertebrates, but Glycoglycerolipids are not widely distributed in vertebrates, but 3-O-sulfated galactosyldiacylglycerol (seminolipid) makes up 3-O-sulfated galactosyldiacylglycerol (seminolipid) makes up 90% of the glycolipid in mammalian testes. 90% of the glycolipid in mammalian testes. Gal3st1Gal3st1-null males -null males are infertile due to an early block in spermatogenesis.are infertile due to an early block in spermatogenesis.
Glycoglycerolipids are not widely distributed in vertebrates, but Glycoglycerolipids are not widely distributed in vertebrates, but 3-O-sulfated galactosyldiacylglycerol (seminolipid) makes up 3-O-sulfated galactosyldiacylglycerol (seminolipid) makes up 90% of the glycolipid in mammalian testes. 90% of the glycolipid in mammalian testes. Gal3st1Gal3st1-null males -null males are infertile due to an early block in spermatogenesis.are infertile due to an early block in spermatogenesis.
Glycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchors
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
ObjectivesObjectivesObjectivesObjectives
Glycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchors
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
ObjectivesObjectivesObjectivesObjectives
GlcCer based glycolipid families:GlcCer based glycolipid families:-All share a lactosylceramide (LacCer) coreAll share a lactosylceramide (LacCer) core-Nomenclature is based on the next sugars in the neutral tetrasaccharide Nomenclature is based on the next sugars in the neutral tetrasaccharide corecore-Classified as “neutral glycosphingolipids”, “sulfated glycosphingolipids” or Classified as “neutral glycosphingolipids”, “sulfated glycosphingolipids” or “gangliosides” (sialylated glycosphingolipids)“gangliosides” (sialylated glycosphingolipids)-Nomenclature describes the length of the core and any substituents, Nomenclature describes the length of the core and any substituents, number the sugars from the reducing (Cer) end out by roman numeralsnumber the sugars from the reducing (Cer) end out by roman numerals-Biosynthesized stepwise by individual glycosphingolipids, some of which Biosynthesized stepwise by individual glycosphingolipids, some of which are glycolipid-specific, others of which also make glycoprotein glycansare glycolipid-specific, others of which also make glycoprotein glycans
GlcCer based glycolipid families:GlcCer based glycolipid families:-All share a lactosylceramide (LacCer) coreAll share a lactosylceramide (LacCer) core-Nomenclature is based on the next sugars in the neutral tetrasaccharide Nomenclature is based on the next sugars in the neutral tetrasaccharide corecore-Classified as “neutral glycosphingolipids”, “sulfated glycosphingolipids” or Classified as “neutral glycosphingolipids”, “sulfated glycosphingolipids” or “gangliosides” (sialylated glycosphingolipids)“gangliosides” (sialylated glycosphingolipids)-Nomenclature describes the length of the core and any substituents, Nomenclature describes the length of the core and any substituents, number the sugars from the reducing (Cer) end out by roman numeralsnumber the sugars from the reducing (Cer) end out by roman numerals-Biosynthesized stepwise by individual glycosphingolipids, some of which Biosynthesized stepwise by individual glycosphingolipids, some of which are glycolipid-specific, others of which also make glycoprotein glycansare glycolipid-specific, others of which also make glycoprotein glycans
Subfamily series Structure Abbreviation
Lacto Galβ1-3GlcNAcβ1-3Galβ1-4GlcβCer Lc4Cer
Neolacto Galβ1-4GlcNAcβ1-3Galβ1-4GlcβCer nLc4Cer
Ganglio Galβ1-3GalNAcβ1-4Galβ1-4GlcβCer Gg4Cer
Globo GalNAcβ1-3Galα1-4Galβ1-4GlcβCer Gb4Cer
Lactosylceramide (LacCer)
NeuAc 3 Gal 3 GalNAc 4 (NeuAc 8 NeuAc 3) Gal 4 Glc Cer
Ganglioside GT1bGanglioside GT1b
Gal GalNAc
Gal GlcNeuAc
NeuAc
NeuAc
Gangliosides are embedded in the extracellular leaflet of the Gangliosides are embedded in the extracellular leaflet of the plasma membrane with their glycans extending outwardplasma membrane with their glycans extending outward
DeMarco & Woods (2009) Glycobiology 19, 344DeMarco & Woods (2009) Glycobiology 19, 344
Rat cerebellar granule cell axons in culture immunostained for ganglioside GD1aRat cerebellar granule cell axons in culture immunostained for ganglioside GD1a
HIC (phase) image overlay imageanti-GD1a mAb
Gangliosides are on ALL vertebrate cells, but are the Gangliosides are on ALL vertebrate cells, but are the dominant glycan structures on nerve cellsdominant glycan structures on nerve cells
* non-neuronal cells
The same four structures comprise the great majority The same four structures comprise the great majority of gangliosides in the brains of all mammalsof gangliosides in the brains of all mammals
GM1Cer
GD1bCer
GT1bCer
GD1aCer
(28%)
(26%)
(25%)
(18%)
Glc Gal GalNAc NeuAc
Values are for human; Gangliosides shown constitute 97% of total brain gangliosidesTettamanti et al. (1973) Biochim Biophys Acta 296, 160
Brain ganglioside biosynthesisBrain ganglioside biosynthesis
ST3GAL5ST3GAL5:: “Infantile-onset symptomatic epilepsy syndrome caused by a homozygous “Infantile-onset symptomatic epilepsy syndrome caused by a homozygous loss-of-loss-of-
functionfunction mutation of GM3 synthase” mutation of GM3 synthase” Simpson MA et al. Nature Genet 36, 1225 (2004)Simpson MA et al. Nature Genet 36, 1225 (2004)
B4GALNT1B4GALNT1:: “Alteration of ganglioside biosynthesis responsible for complex hereditary spastic “Alteration of ganglioside biosynthesis responsible for complex hereditary spastic paraplegia” paraplegia” Boukhris et al. Am J Human Genet 93, 118 (2013)Boukhris et al. Am J Human Genet 93, 118 (2013)
Concepts of glycolipid function: Concepts of glycolipid function: ciscis and and transtransConcepts of glycolipid function: Concepts of glycolipid function: ciscis and and transtrans
ciscis: regulation by : regulation by lateral associationlateral associationciscis: regulation by : regulation by lateral associationlateral association
transtrans: regulation by : regulation by cell-cell recognition cell-cell recognition transtrans: regulation by : regulation by cell-cell recognition cell-cell recognition
Note: Because of their long unsaturated lipid chains, glycolipids cluster together, Note: Because of their long unsaturated lipid chains, glycolipids cluster together, along with cholesterol, selected other lipids, and selected proteins, in “lipid rafts”along with cholesterol, selected other lipids, and selected proteins, in “lipid rafts”Note: Because of their long unsaturated lipid chains, glycolipids cluster together, Note: Because of their long unsaturated lipid chains, glycolipids cluster together, along with cholesterol, selected other lipids, and selected proteins, in “lipid rafts”along with cholesterol, selected other lipids, and selected proteins, in “lipid rafts”
Regina Todeschini & Hakomori (2008) Biochim Biophys Acta 1780:421
Glycolipid purification and analysis: Glycolipid purification and analysis: Solvent extract, partition/chromatography, TLCSolvent extract, partition/chromatography, TLCGlycolipid purification and analysis: Glycolipid purification and analysis: Solvent extract, partition/chromatography, TLCSolvent extract, partition/chromatography, TLC
• Homogenize cells or Homogenize cells or tissuestissues
• Add methanol and Add methanol and chloroformchloroform
• Remove precipitated Remove precipitated protein and DNA by protein and DNA by centrifugationcentrifugation
• Isolate glycolipids by Isolate glycolipids by partition and/or partition and/or adsorptive adsorptive chromatographychromatography
• Analyze by TLC Analyze by TLC
Mouse brain gangliosides – silica TLC – resorcinol sialic acid stain
Mouse sialyltransferase mutants
origin -
GlcCer based glycolipid families:GlcCer based glycolipid families:-All share a lactosylceramide (LacCer) coreAll share a lactosylceramide (LacCer) core-Nomenclature is based on the next sugars in the neutral tetrasaccharide Nomenclature is based on the next sugars in the neutral tetrasaccharide corecore-Classified as “neutral glycosphingolipids”, “sulfated glycosphingolipids” or Classified as “neutral glycosphingolipids”, “sulfated glycosphingolipids” or “gangliosides” (sialylated glycosphingolipids)“gangliosides” (sialylated glycosphingolipids)-Nomenclature describes the length of the core and any substituents, Nomenclature describes the length of the core and any substituents, number the sugars from the reducing (Cer) end out by roman numeralsnumber the sugars from the reducing (Cer) end out by roman numerals-Biosynthesized stepwise by individual glycosphingolipids, some of which Biosynthesized stepwise by individual glycosphingolipids, some of which are glycolipid-specific, others of which also make glycoprotein glycansare glycolipid-specific, others of which also make glycoprotein glycans
GlcCer based glycolipid families:GlcCer based glycolipid families:-All share a lactosylceramide (LacCer) coreAll share a lactosylceramide (LacCer) core-Nomenclature is based on the next sugars in the neutral tetrasaccharide Nomenclature is based on the next sugars in the neutral tetrasaccharide corecore-Classified as “neutral glycosphingolipids”, “sulfated glycosphingolipids” or Classified as “neutral glycosphingolipids”, “sulfated glycosphingolipids” or “gangliosides” (sialylated glycosphingolipids)“gangliosides” (sialylated glycosphingolipids)-Nomenclature describes the length of the core and any substituents, Nomenclature describes the length of the core and any substituents, number the sugars from the reducing (Cer) end out by roman numeralsnumber the sugars from the reducing (Cer) end out by roman numerals-Biosynthesized stepwise by individual glycosphingolipids, some of which Biosynthesized stepwise by individual glycosphingolipids, some of which are glycolipid-specific, others of which also make glycoprotein glycansare glycolipid-specific, others of which also make glycoprotein glycans
Subfamily series Structure Abbreviation
Lacto Galβ1-3GlcNAcβ1-3Galβ1-4GlcβCer Lc4Cer
Neolacto Galβ1-4GlcNAcβ1-3Galβ1-4GlcβCer nLc4Cer
Ganglio Galβ1-3GalNAcβ1-4Galβ1-4GlcβCer Gg4Cer
Globo GalNAcβ1-3Galα1-4Galβ1-4GlcβCer Gb4Cer
Lactosylceramide (LacCer)
Example: Total neolactoseries monsialylated glycolipids from Example: Total neolactoseries monsialylated glycolipids from human neutrophils – diversity within a structural themehuman neutrophils – diversity within a structural themeExample: Total neolactoseries monsialylated glycolipids from Example: Total neolactoseries monsialylated glycolipids from human neutrophils – diversity within a structural themehuman neutrophils – diversity within a structural theme
Nimrichter et al (2008) Blood, 112:3744
Neolactoseries monsialylated glycolipids on human neutrophilsNeolactoseries monsialylated glycolipids on human neutrophilsNeolactoseries monsialylated glycolipids on human neutrophilsNeolactoseries monsialylated glycolipids on human neutrophils
Nimrichter et al (2008) Blood,
112:3744
Neolactoseries monsialylated glycolipids on human neutrophilsNeolactoseries monsialylated glycolipids on human neutrophilsNeolactoseries monsialylated glycolipids on human neutrophilsNeolactoseries monsialylated glycolipids on human neutrophils
Nimrichter et al (2008) Blood,
112:3744
Separation of human neutrophil gangliosides by HPLCSeparation of human neutrophil gangliosides by HPLCSeparation of human neutrophil gangliosides by HPLCSeparation of human neutrophil gangliosides by HPLC
Nimrichter et al (2008) Blood,
112:3744
Concepts of glycolipid function: Concepts of glycolipid function: transtrans recognition in health and disease recognition in health and diseaseConcepts of glycolipid function: Concepts of glycolipid function:
transtrans recognition in health and disease recognition in health and disease
• Bacterial toxins bind to glycolipidsBacterial toxins bind to glycolipids– Shigatoxin (verotoxin) binds to the neutral glycosphingolipid Shigatoxin (verotoxin) binds to the neutral glycosphingolipid
GbGb33 (Gal (Galα1-α1-4Gal4Galβ1-4β1-4GlcGlcβ1-β1-Cer)Cer)
– Cholera and E. Coli enterotoxins bind to the ganglioside Cholera and E. Coli enterotoxins bind to the ganglioside GM1 (GalGM1 (Galβ1-3β1-3GalNAcGalNAcβ1-4(β1-4(NeuAcNeuAcα2-3)α2-3)GalGalβ1-4β1-4GlcGlcβ1-β1-Cer)Cer)
– Tetanus and botulinum neurotoxins toxins bind to nervous Tetanus and botulinum neurotoxins toxins bind to nervous system gangliosides with different specificitiessystem gangliosides with different specificities
• A brain lectin, myelin-associated glycoprotein (MAG), A brain lectin, myelin-associated glycoprotein (MAG), binds to gangliosides GD1a and GT1b to meidate binds to gangliosides GD1a and GT1b to meidate axon-myelin interactions*axon-myelin interactions*
• An endothelial cell lectin, E-selectin, binds to An endothelial cell lectin, E-selectin, binds to sialylated fucosylated glycolipids on human sialylated fucosylated glycolipids on human neutrophils to initiate inflammation*neutrophils to initiate inflammation*
* These lectins will be discussed in a later lecture* These lectins will be discussed in a later lecture
Research correlation: Multivalent toxin inhibitor Research correlation: Multivalent toxin inhibitor mimics glycolipid in the cell membrane mimics glycolipid in the cell membrane
Research correlation: Multivalent toxin inhibitor Research correlation: Multivalent toxin inhibitor mimics glycolipid in the cell membrane mimics glycolipid in the cell membrane
LEFT: ABLEFT: AB55 bacterial toxins (cholera toxin shown) have bacterial toxins (cholera toxin shown) have
5 glycolipid cell surface binding subunits surrounding a 5 glycolipid cell surface binding subunits surrounding a “payload” toxic subunit (not shown) that is inserted into “payload” toxic subunit (not shown) that is inserted into the cell only after binding.the cell only after binding.
LEFT: ABLEFT: AB55 bacterial toxins (cholera toxin shown) have bacterial toxins (cholera toxin shown) have
5 glycolipid cell surface binding subunits surrounding a 5 glycolipid cell surface binding subunits surrounding a “payload” toxic subunit (not shown) that is inserted into “payload” toxic subunit (not shown) that is inserted into the cell only after binding.the cell only after binding.
Merritt et al. (1994) Protein Sci 3:166
RIGHT: Taking RIGHT: Taking advantage of the ABadvantage of the AB55
structure of structure of vertotoxin, and its vertotoxin, and its GbGb33 specific binding, specific binding,
Kitov et al Kitov et al synthesized a synthesized a “starfish” shaped “starfish” shaped inhibitor with five inhibitor with five arms, each carrying arms, each carrying two copies of Gbtwo copies of Gb33. .
RIGHT: Taking RIGHT: Taking advantage of the ABadvantage of the AB55
structure of structure of vertotoxin, and its vertotoxin, and its GbGb33 specific binding, specific binding,
Kitov et al Kitov et al synthesized a synthesized a “starfish” shaped “starfish” shaped inhibitor with five inhibitor with five arms, each carrying arms, each carrying two copies of Gbtwo copies of Gb33. .
Kitov et al. (2000) Nature 403:669
Research correlation: Multivalent toxin inhibitor Research correlation: Multivalent toxin inhibitor mimics glycolipid in the cell membrane mimics glycolipid in the cell membrane
Research correlation: Multivalent toxin inhibitor Research correlation: Multivalent toxin inhibitor mimics glycolipid in the cell membrane mimics glycolipid in the cell membrane
ABOVE: “Starfish”GbABOVE: “Starfish”Gb33 blocks verotoxin binding at sub-nM blocks verotoxin binding at sub-nM
concentrations – a million times more potent than Gbconcentrations – a million times more potent than Gb33
ABOVE: “Starfish”GbABOVE: “Starfish”Gb33 blocks verotoxin binding at sub-nM blocks verotoxin binding at sub-nM
concentrations – a million times more potent than Gbconcentrations – a million times more potent than Gb33
Kitov et al. (2000) Nature 403:669
Kitov et al. (2000) Nature 403:669
Right: “Starfish”GbRight: “Starfish”Gb33 crystallized with verotoxin – crystallized with verotoxin –
a perfect pentomeric sandwicha perfect pentomeric sandwichRight: “Starfish”GbRight: “Starfish”Gb33 crystallized with verotoxin – crystallized with verotoxin –
a perfect pentomeric sandwicha perfect pentomeric sandwich
Glycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchors
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
ObjectivesObjectivesObjectivesObjectives
Glycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchors
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
ObjectivesObjectivesObjectivesObjectives
A small but diverse group of proteins are attached to A small but diverse group of proteins are attached to the cell surface by a “glycosylphosphatidylinositol” the cell surface by a “glycosylphosphatidylinositol” (GPI) anchor(GPI) anchor
A small but diverse group of proteins are attached to A small but diverse group of proteins are attached to the cell surface by a “glycosylphosphatidylinositol” the cell surface by a “glycosylphosphatidylinositol” (GPI) anchor(GPI) anchor
GPI anchors have a minimal (core) structure (black font) with variable additional glycan, fatty acid ester, and phosphoethanolamine groups (blue font)
Taylor and Drikamer (2011) Introduction to Glycobiology
Essentials of Glycobiology Second Edition
GPI anchors are GPI anchors are complex & diversecomplex & diverseGPI anchors are GPI anchors are complex & diversecomplex & diverse
• Glucosamine with Glucosamine with free amine – rarefree amine – rare
• Phosphodiesters at Phosphodiesters at each endeach end
• Diverse Diverse modifications along modifications along the corethe core
R3
A group of select proteins are GPI anchored*A group of select proteins are GPI anchored*A group of select proteins are GPI anchored*A group of select proteins are GPI anchored*MammalsMammals
Erythrocyte CD59 and decay Erythrocyte CD59 and decay acceleration factor (DAF)acceleration factor (DAF) complement regulationcomplement regulation
Alkaline phosphataseAlkaline phosphatase cell-surface hydrolasecell-surface hydrolase
5′-Nucleotidase5′-Nucleotidase cell-surface hydrolasecell-surface hydrolase
Renal dipeptidaseRenal dipeptidase cell-surface hydrolasecell-surface hydrolase
TrehalaseTrehalase cell-surface hydrolasecell-surface hydrolase
Neural cell adhesion Neural cell adhesion molecule 120 (NCAM-120)molecule 120 (NCAM-120) adhesion moleculeadhesion molecule
Neural cell adhesion Neural cell adhesion molecule TAG-1molecule TAG-1 adhesion moleculeadhesion molecule
CD58CD58 adhesion moleculeadhesion molecule
FcFcγγIII receptorIII receptor Fc receptorFc receptor
Ciliary neurotrophic factor Ciliary neurotrophic factor receptor (CNTFR) α subunitreceptor (CNTFR) α subunit neural receptorneural receptor
Glial-cell-derived Glial-cell-derived neurotrophic factor receptor neurotrophic factor receptor (GDNFR) α subunit(GDNFR) α subunit
neural receptorneural receptor
CD14CD14 LPS receptorLPS receptor
Prion protein (PrP)Prion protein (PrP) unknownunknown
Glypican family of GPI-Glypican family of GPI-anchored proteoglycansanchored proteoglycans
extracellular matrix extracellular matrix componentcomponent
Trypanosoma bruceTrypanosoma brucei i variant surface variant surface glycoprotein (VSG)glycoprotein (VSG)
protective coatprotective coat
Leishmania majorLeishmania major promastigote surface promastigote surface protease (PSP)protease (PSP)
bound complement bound complement degradationdegradation
Trypanosoma cruziTrypanosoma cruzi GPI- GPI-anchored mucinsanchored mucins host cell invasionhost cell invasion
Plasmodium falciparumPlasmodium falciparum merozoite surface protein 1 merozoite surface protein 1 (MSP-1)(MSP-1)
erythrocyte invasionerythrocyte invasion
Toxoplasma gondiiToxoplasma gondii surface surface antigen 1 (SAG-1)antigen 1 (SAG-1) host cell invasionhost cell invasion
Entamoeba histolyticaEntamoeba histolytica GPI GPI proteophosphoglycansproteophosphoglycans virulence factorvirulence factor
ParasitesParasites
*plus some in yeast, plants, some other species*plus some in yeast, plants, some other species
Variety is the spice of… GPI anchorsVariety is the spice of… GPI anchorsVariety is the spice of… GPI anchorsVariety is the spice of… GPI anchors
Essentials of Glycobiology Second Edition
Glycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchors
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
ObjectivesObjectivesObjectivesObjectives
Glycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchors
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
ObjectivesObjectivesObjectivesObjectives
Preassembled GPI Preassembled GPI anchors are covalently anchors are covalently transferred transferred en blocen bloc via via amide linkage to an amide linkage to an amino acid near the amino acid near the carboxy terminus of a carboxy terminus of a nacient protein, at the nacient protein, at the same time releasing same time releasing the C-terminal protein the C-terminal protein fragment. This occurs fragment. This occurs in the ER.in the ER.
Although there is no Although there is no “consensus sequence,” “consensus sequence,” per se, for GPI transfer, per se, for GPI transfer, likely sites are identified likely sites are identified by their structural by their structural features.features.
Preassembled GPI Preassembled GPI anchors are covalently anchors are covalently transferred transferred en blocen bloc via via amide linkage to an amide linkage to an amino acid near the amino acid near the carboxy terminus of a carboxy terminus of a nacient protein, at the nacient protein, at the same time releasing same time releasing the C-terminal protein the C-terminal protein fragment. This occurs fragment. This occurs in the ER.in the ER.
Although there is no Although there is no “consensus sequence,” “consensus sequence,” per se, for GPI transfer, per se, for GPI transfer, likely sites are identified likely sites are identified by their structural by their structural features.features.
Essentials of Glycobiology Second Edition
Like N-linked glycan biosynthesis, the precursor starts assembly on the cytoplasmic Like N-linked glycan biosynthesis, the precursor starts assembly on the cytoplasmic face of the ER, then is flipped inside for further processing. GlcNAc transfer and face of the ER, then is flipped inside for further processing. GlcNAc transfer and deacetylation, inositol fatty acid esterification, and multiple ethanolamine phosphate deacetylation, inositol fatty acid esterification, and multiple ethanolamine phosphate group transfers by separate enzymes are noteworthy.group transfers by separate enzymes are noteworthy.
Like N-linked glycan biosynthesis, the precursor starts assembly on the cytoplasmic Like N-linked glycan biosynthesis, the precursor starts assembly on the cytoplasmic face of the ER, then is flipped inside for further processing. GlcNAc transfer and face of the ER, then is flipped inside for further processing. GlcNAc transfer and deacetylation, inositol fatty acid esterification, and multiple ethanolamine phosphate deacetylation, inositol fatty acid esterification, and multiple ethanolamine phosphate group transfers by separate enzymes are noteworthy.group transfers by separate enzymes are noteworthy.
Essentials of Glycobiology Second Edition
GPI anchor synthesis has been studied most extensively in parasites, which express GPI anchor synthesis has been studied most extensively in parasites, which express millions of GPI-anchored proteins and glycans on the surface of each cell. millions of GPI-anchored proteins and glycans on the surface of each cell. GPI anchor synthesis has been studied most extensively in parasites, which express GPI anchor synthesis has been studied most extensively in parasites, which express millions of GPI-anchored proteins and glycans on the surface of each cell. millions of GPI-anchored proteins and glycans on the surface of each cell.
http://www.lifesci.dundee.ac.uk/people/mike-ferguson
African sleeping sickness Chagas diseaseleishmaniasis
GPI anchor synthesis in parasites is complex with some interesting twists, such as GPI anchor synthesis in parasites is complex with some interesting twists, such as fatty acid remodeling. Since GPI anchored coat proteins are virulence factors, they fatty acid remodeling. Since GPI anchored coat proteins are virulence factors, they are being exploited as targets for therapy.are being exploited as targets for therapy.
GPI anchor synthesis in parasites is complex with some interesting twists, such as GPI anchor synthesis in parasites is complex with some interesting twists, such as fatty acid remodeling. Since GPI anchored coat proteins are virulence factors, they fatty acid remodeling. Since GPI anchored coat proteins are virulence factors, they are being exploited as targets for therapy.are being exploited as targets for therapy.
Essentials of Glycobiology
Second Edition
To study the structures and functions of GPI anchored proteins, they can be To study the structures and functions of GPI anchored proteins, they can be released under biologically compatible conditions using bacterial released under biologically compatible conditions using bacterial phosphatidylinositol-specific phospholipase C (PIPLC), or decomposed specifically phosphatidylinositol-specific phospholipase C (PIPLC), or decomposed specifically by nitrous acid, which cleaves at the glucosamine residue forming a 2,5-by nitrous acid, which cleaves at the glucosamine residue forming a 2,5-anhydromannose residue.anhydromannose residue.
To study the structures and functions of GPI anchored proteins, they can be To study the structures and functions of GPI anchored proteins, they can be released under biologically compatible conditions using bacterial released under biologically compatible conditions using bacterial phosphatidylinositol-specific phospholipase C (PIPLC), or decomposed specifically phosphatidylinositol-specific phospholipase C (PIPLC), or decomposed specifically by nitrous acid, which cleaves at the glucosamine residue forming a 2,5-by nitrous acid, which cleaves at the glucosamine residue forming a 2,5-anhydromannose residue.anhydromannose residue.
Essentials of Glycobiology Second Edition
Glycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchors
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
ObjectivesObjectivesObjectivesObjectives
Glycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchors
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
ObjectivesObjectivesObjectivesObjectives
Clinical correlation: defects in glycolipid degradationClinical correlation: defects in glycolipid degradationClinical correlation: defects in glycolipid degradationClinical correlation: defects in glycolipid degradation
Disease name Disease name (glycolipid)(glycolipid) Enzyme or protein deficiencyEnzyme or protein deficiency Clinical symptomsClinical symptoms
Tay–Sachs (GM2)Tay–Sachs (GM2) β-β-hexosaminidase Ahexosaminidase A neurodegeneration, death by 4 yearsneurodegeneration, death by 4 years
Sandhoff (GM2)Sandhoff (GM2) β-β-hexosaminidase A and Bhexosaminidase A and B neurodegeneration, death by 4 yearsneurodegeneration, death by 4 years
GM1 gangliosidosis GM1 gangliosidosis (GM1)(GM1) β-β-galactosidasegalactosidase progressive neurological disease and skeletal progressive neurological disease and skeletal
dysplasia in severe infantile formdysplasia in severe infantile form
Fabry*Fabry*(Gb3)(Gb3) α-α-galactosidasegalactosidase
severe pain, angiokeratoma, corneal severe pain, angiokeratoma, corneal opacities, death from renal or cerebrovascular opacities, death from renal or cerebrovascular diseasedisease
Gaucher’s*Gaucher’s*(GlcCer)(GlcCer) β-β-glucoceramidaseglucoceramidase hepatosplenomegaly hepatosplenomegaly
neurodegeneration (severe form only)neurodegeneration (severe form only)
KrabbeKrabbe(GalCer)(GalCer) β-β-galactoceramidasegalactoceramidase early onset with progression to severe mental early onset with progression to severe mental
and motor deteriorationand motor deterioration
Metachromatic Metachromatic leukodystrophy leukodystrophy
(sulfatide)(sulfatide)
arylsulfatase A arylsulfatase A (cerebroside sulfatase)(cerebroside sulfatase)
mental regression, peripheral neuropathy, mental regression, peripheral neuropathy, seizures, dementiaseizures, dementia
Saposin deficiencySaposin deficiency(many)(many) saposin precursorsaposin precursor neurodegeneration, death by 4 yearsneurodegeneration, death by 4 years
*enzyme replacement therapy available*enzyme replacement therapy availableEssentials of Glycobiology
Second Edition
Gaucher disease – cause, symptoms and treatmentGaucher disease – cause, symptoms and treatmentGaucher disease – cause, symptoms and treatmentGaucher disease – cause, symptoms and treatment
Hepatosplenomegaly: Grossly enlarged liver and spleen
http://www.gauchercare.com/
The cure: enzyme replacement therapy
Andersson et al.. (2008) Pediatrics 122:1182
A new direction – substrate reduction therapyA new direction – substrate reduction therapyA new direction – substrate reduction therapyA new direction – substrate reduction therapy
n-butyl-deoxynojirimycin = Miglustat = Zavesca®
Glycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchors
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
ObjectivesObjectivesObjectivesObjectives
Glycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchors
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
ObjectivesObjectivesObjectivesObjectives
Clinical correlation: Paroxysmal nocturnal hemoglobinuriaClinical correlation: Paroxysmal nocturnal hemoglobinuriaClinical correlation: Paroxysmal nocturnal hemoglobinuriaClinical correlation: Paroxysmal nocturnal hemoglobinuria
http://www.bioch.ox.ac.uk/glycob/archive/
CD59, a GPI-anchored “complement defense protein” terminal complement complex
http://trialx.com/
The cause, somatic mutation of the PIG-A gene resulting in failure to transfer GlcNAc to phosphatidylinositol, and loss of multiple GPI-anchored complement control proteins.
Essentials of Glycobiology
Clinical correlation: Paroxysmal nocturnal hemoglobinuriaClinical correlation: Paroxysmal nocturnal hemoglobinuriaClinical correlation: Paroxysmal nocturnal hemoglobinuriaClinical correlation: Paroxysmal nocturnal hemoglobinuria
Kelly R J et al. Blood (2011)117:6786
Anti-complement protein 5 treatment improves outcomesAnti-complement protein 5 treatment improves outcomesAnti-complement protein 5 treatment improves outcomesAnti-complement protein 5 treatment improves outcomes
per year per year
Glycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchorsGlycolipids and GPI anchors
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
• Learn the structures, and some functions of the most Learn the structures, and some functions of the most abundant vertebrate glycolipidsabundant vertebrate glycolipids
• Glucosylceramide and the skin barrier• Galactosylceramide & sulfatide in myelin• Glycolipids in cell-cell interactions and membrane receptor
modulation
• Learn the structures, distribution and biosynthesis of Learn the structures, distribution and biosynthesis of GPI anchorsGPI anchors
• GPI-anchored proteins and their anchor structures in people and parasites
• GPI anchor biosynthesis and en bloc transfer
• Glycolipids and GPI anchors in diseaseGlycolipids and GPI anchors in disease• Glycolipids and lysosomal storage diseases• GPI anchors in anemia
ObjectivesObjectivesObjectivesObjectives