Heterogeneity of N-linked sugar chains of apolipoprotein B-100 in Watanabe heritable hyperlipidemic and fasting rabbits.

Tsunemitsu, Masahiko; Ishikawa, Yuichi; Taniguchi, Takahiro; Fukuzaki, Hisashi

doi:10.1161/01.atv.10.3.386

Cited by 7 publications

(1 citation statement)

References 49 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A cluster of oligosaccharides has been localized to the putative LDL receptor domain and to some heparin-binding sites of human apo B-100 [4], and it is possible that oligosaccharides protect the precise function of this region of the molecule. In Watanabe hyperlipidaemic rabbits, apo B-100 oligosaccharides were poorly sialylated, supporting a hypothesis that altered surface charge of LDL particles may play a role in atherosclerotic development [41]. In chylomicronretention disease, which is characterized by malabsorption and low concentrations of plasma lipids and cholesterol, there are no detectable circulating chylomicrons.…”

Section: Discussionmentioning

confidence: 66%

Human small-intestinal apolipoprotein B-48 oligosaccharide chains

Sasak

Lown

Colburn

1991

Biochemical Journal

View full text Add to dashboard Cite

Hepatic apolipoprotein (apo) B-100 isolated from human plasma is known to contain N-linked oligosaccharides of high-mannose-type and complex-type structures. Sequencing data have revealed that apo B-48 of small-intestinal origin, which represents about 48% of apo B-100 polypeptide from the N-terminus, possesses six potential sites for N-linked oligosaccharides, of which five are likely to be glycosylated. The characterization of the carbohydrate moiety of apo B-48 is the focus of this study. Apo B-48 was labelled with L-[35S]methionine and D-[3H]glucosamine in organ culture of human small-intestinal explants. N-Glycanase treatment resulted in loss of radioactivity from D-[3H]glucosamine-labelled but not L-[35S]methionine-labelled apo B-48 secreted into the medium, and caused no distinct change in mobility of apo B-48 upon electrophoresis on 5% polyacrylamide gel. Analysis of monosaccharide content revealed the presence of 16.8, 17.8, 13.4, 3.4, 2.4 and 2.3 residues of N-acetylglucosamine, mannose, galactose, fucose, xylose and N-acetylgalactosamine respectively. Small-intestinal apo B-48 from human lymph chylomicrons bound to [14C]concanavalin A, and the binding could be inhibited with methyl alpha-D-mannoside. In addition, wheat-germ, peanut, Limulus, soya-bean and Ulex lectins bound apo B-48 specifically. To characterize the carbohydrate moiety further, N-linked oligosaccharides were released by N-Glycanase treatment and reduced with NaB3H4. Labelled oligosaccharides were separated on a concanavalin A-Sepharose column. The majority (78%) were biantennary complex-type structures, 16% were high-mannose type and 6% (not retained by the column) most probably represented higher-branched oligosaccharides. These results suggest the presence of one high-mannose-type and four biantennary complex-type oligosaccharides, as well as probable O-linked sugars in apo B-48. By the use of h.p.l.c., exoglycosidase treatments and ion-exchange chromatography, a mixture of high-mannose-type species with predominant Man8GlcNAc2 as well as monosialylated, desialylated and fucosylated forms of complex-type oligosaccharides were detected.

show abstract

Section: Discussionmentioning

confidence: 66%

Human small-intestinal apolipoprotein B-48 oligosaccharide chains

Sasak

Lown

Colburn

1991

Biochemical Journal

View full text Add to dashboard Cite

show abstract

Association of N-glycosylation of apolipoprotein B-100 with plasma cholesterol levels in Watanabe heritable hyperlipidemic rabbits

et al. 1992

View full text Add to dashboard Cite

Relation of N-glycosylation of apolipoprotein B-100 to cellular metabolism of low density lipoprotein

et al. 1994

View full text Add to dashboard Cite

We studied the functional role of N-linked sugar chains of apolipoprotein (apo) B-100 of low density lipoprotein (LDL) in cholesterol metabolism. The N-linked sugar chains of apo B-100 of LDL obtained from four homozygous Watanabe heritable hyperlipidemic (WHHL) rabbits were liberated by hydrazinolysis, followed by NaB3H4 reduction and were fractionated by paper electrophoresis and column chromatography. They consisted of one neutral (N) and two acidic (A1, A2) fractions. The ratio of apo B-100 acidic fractions (A1+A2) varied among 4 WHHL rabbits. Serial measurements of serum cholesterol levels showed that they decreased with aging in each of 4 WHHL rabbits. We investigated the relation of the ratio of acidic sugar chains of apo B-100 to the serum cholesterol levels. Reciprocals of the serum cholesterol levels were significantly correlated with the ratio of acidic sugar chains of apo B-100 (r = 0.901, P < 0.001). To elucidate the role of N-linked sugar chains of apo B-100, we investigated cellular uptake of LDL in normal rabbit skin fibroblasts. The amounts of association, degradation and cholesteryl esterification of LDL with a lower ratio of acidic sugar chains at 37 degrees C were greater than those of LDL with a higher ratio of acidic sugar chains. These results suggest that N-glycosylation of apo B-100 may be related with serum cholesterol levels and N-linked sugar chains of apo B-100 may play an important role in cellular metabolism of LDL.

show abstract

Heterogeneity of N-linked sugar chains of apolipoprotein B-100 in Watanabe heritable hyperlipidemic and fasting rabbits.

Cited by 7 publications

References 49 publications

Human small-intestinal apolipoprotein B-48 oligosaccharide chains

Human small-intestinal apolipoprotein B-48 oligosaccharide chains

Association of N-glycosylation of apolipoprotein B-100 with plasma cholesterol levels in Watanabe heritable hyperlipidemic rabbits

Relation of N-glycosylation of apolipoprotein B-100 to cellular metabolism of low density lipoprotein

Contact Info

Product

Resources

About