Clofibrate inhibits membrane trafficking to the Golgi complex and induces its retrograde movement to the endoplasmic reticulum.
Insights into the function of the Golgi complex have been provided by experiments performed with various inhibitors of membrane trafficking, such as the macrocyclic lactone brefeldin A (BFA), a compound that inhibits constitutive secretion, prevents the formation of coatomer-coated transport vesicles, and stimulates the retrograde movement of Golgi resident enzymes back to the ER. We show here that the structurally unrelated compound clofibrate, a peroxisome proliferator (PP) and hypolipidemic agent, also reversibly disrupts the morphological and functional integrity of the Golgi complex in a manner similar to BFA. In the presence of clofibrate, the forward transport of newly synthesized secretory proteins from the ER to the Golgi is dramatically inhibited. Moreover, clofibrate causes Golgi membranes to travel rapidly in a microtubule-dependent manner back to the ER, forming a hybrid ER-Golgi tubulovesicular membrane network. These affects appear to be independent of clofibrate's ability to stimulate the PP-activated receptor (PPAR) alpha pathway because other PPAR stimulators (DEHP, WY-14643) did not alter the Golgi complex or induce retrograde trafficking. These data suggest that PPAR alpha-independent, clofibrate-sensitive proteins participate in regulating Golgi-to-ER retrograde membrane transport, and, equally importantly, that clofibrate may be used as a pharmacological tool for investigating Golgi membrane dynamics.
de Figueiredo
P
P
Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853, USA.
Brown
W J
WJ
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D001692:Biological Transport / Q000187:drug effects; D002478:Cells, Cultured; D002994:Clofibrate / Q000494:pharmacology*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D004051:Diethylhexyl Phthalate / Q000494:pharmacology; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D006056:Golgi Apparatus / Q000378:metabolism*; D000960:Hypolipidemic Agents / Q000494:pharmacology*; D008099:Liver / Q000166:cytology / Q000201:enzymology; D008361:Mannosidases / Q000032:analysis / Q000276:immunology; D008562:Membrane Glycoproteins; D008870:Microtubules / Q000187:drug effects / Q000378:metabolism; D015739:Nocodazole / Q000494:pharmacology; D020025:Peroxisome Proliferators / Q000494:pharmacology; D020675:Peroxisomes / Q000378:metabolism; D011743:Pyrimidines / Q000494:pharmacology; D051381:Rats; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D014759:Viral Envelope Proteins / Q000493:pharmacokinetics
D000970:Antineoplastic Agents; D005227:Fatty Acids; C028391:G protein, vesicular stomatitis virus; D000960:Hypolipidemic Agents; D008562:Membrane Glycoproteins; D020025:Peroxisome Proliferators; D011743:Pyrimidines; D018160:Receptors, Cytoplasmic and Nuclear; D014157:Transcription Factors; D014759:Viral Envelope Proteins; C006253:pirinixic acid; D003577:Cytochrome P-450 Enzyme System; D004051:Diethylhexyl Phthalate; D008361:Mannosidases; C038829:mannosyl-oligosaccharide 1,3 - 1,6-alpha-mannosidase; D002994:Clofibrate; D015739:Nocodazole