Sphingomyelin is synthesized in the cis Golgi.
We have employed in vitro a truncated ceramide analogue with 8 carbon atoms in the sphingosine and the fatty acyl residue, each, to investigate the activity of various membrane fractions to synthesize truncated sphingomyelin. This shortened ceramide readily diffuses through membranes and therefore can easily find access to the lumina of intact organelles. Sphingomyelin synthase activity resides in the Golgi apparatus, and after sucrose density gradient centrifugation of Golgi-enriched fractions sphingomyelin synthesis follows a cis Golgi marker enzyme.
Jeckel
D
D
Institut für Biochemie I, Heidelberg, FRG.
Karrenbauer
A
A
Birk
R
R
Schmidt
R R
RR
Wieland
F
F
D000818:Animals; D002458:Cell Fractionation; D002499:Centrifugation, Density Gradient; D002518:Ceramides / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism*; D007425:Intracellular Membranes / Q000378:metabolism; D008099:Liver / Q000648:ultrastructure*; D015388:Organelles / Q000378:metabolism; D010770:Phosphotransferases / Q000378:metabolism; D051381:Rats; D013109:Sphingomyelins / Q000096:biosynthesis*; D013110:Sphingosine / Q000378:metabolism; D017855:Transferases (Other Substituted Phosphate Groups)
D002518:Ceramides; D013109:Sphingomyelins; D010770:Phosphotransferases; D017855:Transferases (Other Substituted Phosphate Groups); C030012:UDP-N-acetylglucosamine-lysosomal-enzyme-N-acetylglucosaminephosphotransferase; C019863:ceramide cholinephosphotransferase; D013110:Sphingosine