Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1999 Oct 18;1441(1):36-50.
doi: 10.1016/s1388-1981(99)00138-9.

Inactivation of microsomal triglyceride transfer protein impairs the normal redistribution but not the turnover of newly synthesized glycerolipid in the cytosol, endoplasmic reticulum and Golgi of primary rat hepatocytes

A Hebbachi  1 , G F Gibbons
Affiliations

Inactivation of microsomal triglyceride transfer protein impairs the normal redistribution but not the turnover of newly synthesized glycerolipid in the cytosol, endoplasmic reticulum and Golgi of primary rat hepatocytes

A Hebbachi et al. Biochim Biophys Acta. .

Abstract

The requirements for microsomal triglyceride transfer protein (MTP) during the turnover and transfer of glycerolipids from intracellular compartments into secretory very low-density lipoprotein (VLDL) were studied by pre-labelling lipids with [(3)H]glycerol and [(14)C]oleate in primary cultures of rat hepatocytes. The intracellular redistribution of pre-labelled glycerolipids was then compared at the end of subsequent chase periods during which the MTP inhibitor BMS-200150 was either present or absent in the medium. Inhibition of MTP resulted in a decreased output of VLDL triacylglycerol (TAG) and a delayed removal of labelled TAG from the cytosol and from the membranes of the smooth endoplasmic reticulum (SER), the cis- and the trans-Golgi. Inactivation of MTP did not decrease the bulk lipolytic turnover of cellular TAG as reflected by changes in its [(3)H]glycerol:[(14)C]oleate ratios. However, a larger proportion of the resultant TAG fatty acids was re-esterified and remained with the membranes of the various subcellular fractions rather than emerging as VLDL. The effects of BMS-200150 on the pattern of phospholipid (PL) mechanism and redistribution suggested that inhibition of MTP prevented the normal lipolytic transfer of PL-derived fatty acids out of the SER, cis- and trans-Golgi membrane pools. Finally, changes in the (14)C specific radioactivities of the cytosolic and membrane pools of TAG suggested that inhibition of MTP prevented a normal influx of relatively unlabelled fatty acids into these pools during the chase period.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

Publication types

MeSH terms

LinkOut - more resources

-