Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
INFLUENCE OF TRIACYLGLYCEROL BIOSYNTHESIS RATE ON THE ASSEMBLY OF APO-B-100-CONTAINING LIPOPROTEINS IN HEP G2 CELLS
Autore:
BOREN J; RUSTAEUS S; WETTESTEN M; ANDERSSON M; WIKLUND A; OLOFSSON SO;
Indirizzi:
UNIV GOTEBORG,DEPT MED BIOCHEM,MEDICINAREGATAN 9 S-41390 GOTHENBURG SWEDEN UNIV GOTEBORG,DEPT MED BIOCHEM S-41390 GOTHENBURG SWEDEN UNIV GOTEBORG,WALLENBERG LAB GOTHENBURG SWEDEN
Titolo Testata:
Arteriosclerosis and thrombosis
fascicolo: 12, volume: 13, anno: 1993,
pagine: 1743 - 1754
SICI:
1049-8834(1993)13:12<1743:IOTBRO>2.0.ZU;2-L
Fonte:
ISI
Lingua:
ENG
Soggetto:
LOW-DENSITY-LIPOPROTEIN; APOLIPOPROTEIN-B SECRETION; APO-B; ENDOPLASMIC-RETICULUM; PULSE-CHASE; OLEIC-ACID; FATTY-ACID; HEPATOCYTES; LIVER; MEMBRANE;
Keywords:
APO-B-100; HEP G2 CELLS; TRIACYLGLYCEROL BIOSYNTHESIS;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Citazioni:
41
Recensione:
Indirizzi per estratti:
Citazione:
J. Boren et al., "INFLUENCE OF TRIACYLGLYCEROL BIOSYNTHESIS RATE ON THE ASSEMBLY OF APO-B-100-CONTAINING LIPOPROTEINS IN HEP G2 CELLS", Arteriosclerosis and thrombosis, 13(12), 1993, pp. 1743-1754

Abstract

Apolipoprotein B-100 (apoB-100) appears in three forms in the endoplasmic reticulum of Hep G2 cells: (1) tightly bound to the membrane, ie,not extractable by sodium carbonate. This form is glycosylated but protease sensitive when present in intact microsomes, suggesting that itis only partially translocated to the microsomal lumen; (2) extractable by sodium carbonate and present on low-density lipoprotein-very-low-density lipoprotein (LDL-VLDL)-like particles. This form is glycosylated and secreted into the medium; and (3) extractable by sodium carbonate but having a higher density than the LDL-VLDL-like particles. Thisform, referred to as Fraction I, is glycosylated and protected against proteases when present in intact microsomal vesicles, indicating that it is completely translocated to the luminal side of the microsomal membrane. Fraction I is not secreted into the medium, but it disappears with time from the cell, suggesting that it is degraded. Oleic acid induced a 2.7-fold increase in the rate of the biosynthesis of triacylglycerol but not of phosphatidylcholine in Hep G2 cells. Incubation ofthe cells with oleic acid had no significant effect on the rate of initiation of the apoB-100-containing lipoproteins, nor did it influencethe amount of apoB-100 that was associated with the membrane or the turnover of apoB-100 in the membrane. Instead, it increased the proportion of the nascent apoB polypeptides on initiated lipoproteins that was converted into full-length apoB-100 on LDL-VLDL-like particles, giving rise to an increased amount of these particles in the lumen of the secretory pathway. Pulse-chase experiments showed that incubation witholeic acid gave rise to an increased formation of LDL-VLDL-like particles ion behalf of the formation of Fraction I. This effect of oleic acid could partially explain the protective effect of the fatty acid onapoB-100, preventing it from undergoing posttranslational degradation.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 28/03/20 alle ore 09:04:47