Acetylation in vitro of constituent polypeptides by smooth endoplasmic reticulum (SER) and Golgi membrane fractions

Conference · Thu May 01 00:00:00 EDT 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:7119608

Sambasivam, H; Murray, R K

Many polypeptides of the membranes of the ER are phosphorylated. To determine if any such polypeptides are acetylated, microsomal and other classical subcellular fractions were incubated with (/sup 3/H) acetyl-CoA; the specific activity of the microsomal fraction (MF) was the greatest. SDS-PAGE revealed that some 20 polypeptides of the MF were acetylated; 2-D electrophoretograms extended this number to approximately 60. Separation of the MF into smooth (S) and rough (R) fractions showed that the great majority of the labelled polypeptides belonged to the former. Isolation of a Golgi fraction revealed that its acetylation activity was approximately 3-fold greater than the SER fraction. Extensive proteolytic digestion of the MF followed by radiochromatography disclosed some 9 components whose precise nature (acetylated amino acids and/or sialic acids, etc.) is under study. Assuming that the majority of the radioactivity is in the former components and that a similar process occurs in vivo, the authors suggest that the Golgi apparatus may be a major site of acetylation of membrane and possibly other proteins.

• Research Organization: Univ. of Toronto, Ontario
• OSTI ID: 7119608
• Report Number(s): CONF-8606151-; TRN: 87-007004
• Journal Information: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Vol. 45:6; Conference: 76. annual meeting of the Federation of American Society for Experimental Biology, Washington, DC, USA, 8 Jun 1986
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ACETYLATION
ENDOPLASMIC RETICULUM
BIOCHEMISTRY
ENZYME ACTIVITY
ORGANOIDS
PROTEINS
ELECTROPHORESIS
IN VITRO
MICROSOMES
SUBCELLULAR DISTRIBUTION
TRACER TECHNIQUES
TRITIUM COMPOUNDS
ACYLATION
CELL CONSTITUENTS
CHEMICAL REACTIONS
CHEMISTRY
DISTRIBUTION
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
ORGANIC COMPOUNDS
550201* - Biochemistry- Tracer Techniques