Tyrosine O-sulfation of the fibrinogen gamma B chain in primary cultures of rat hepatocytes

Journal Article · Wed May 25 04:00:00 UTC 1988 · J. Biol. Chem.; (United States)

OSTI ID:7026916

Hirose, S; Oda, K; Ikehara, Y

Sulfation of fibrinogen was studied in a primary culture of rat hepatocytes. After cells were incubated with (35S)sulfate, 35S-labeled fibrinogen was obtained from the medium by immunoprecipitation and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis/fluorography. It was demonstrated that (35S)sulfate is exclusively incorporated into the gamma B chain, which is a minor variant form found in rat fibrinogen, in addition to a major gamma A chain. When the purified 35S-gamma B chain was digested with carboxypeptidase Y, the radioactivity was almost completely released from the protein, and the labeled product released was identified as tyrosine O-sulfate. Based on the available primary structure of the gamma B chain, the results suggest that sulfation occurs on the tyrosine residue at the second position from its COOH terminus. Pulse-chase experiments using both (3H)leucine and (35S)sulfate showed that 35S-labeled fibrinogen is secreted into the medium much faster than the 3H-labeled molecule. Incubation of cells with monensin, an inhibitor of Golgi function, strongly inhibited the sulfation of fibrinogen. In addition, in vitro sulfation experiments demonstrated that sulfotransferase activity is localized in the Golgi fraction. These results indicate that the sulfation of fibrinogen takes place in the Golgi complex, especially in the trans Golgi region, just before its secretion.

• Research Organization: Fukuoka Univ. School of Medicine (Japan)
• OSTI ID: 7026916
• Journal Information: J. Biol. Chem.; (United States), Journal Name: J. Biol. Chem.; (United States) Vol. 263:15; ISSN JBCHA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINO ACIDS
ANIMAL CELLS
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BLOOD COAGULATION FACTORS
CARBOXYLIC ACIDS
CELL CULTURES
COAGULANTS
DAYS LIVING RADIOISOTOPES
DRUGS
ENZYME ACTIVITY
ENZYMES
EVEN-ODD NUCLEI
FIBRINOGEN
GLOBULINS
HEMATOLOGIC AGENTS
HEMOSTATICS
HYDROXY ACIDS
IMMUNOASSAY
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED COMPOUNDS
LEUCINE
LIGHT NUCLEI
LIVER CELLS
MAMMALS
METABOLISM
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PROTEINS
RADIOISOTOPES
RATS
RODENTS
SOMATIC CELLS
STRUCTURE-ACTIVITY RELATIONSHIPS
SULFATES
SULFUR 35
SULFUR COMPOUNDS
SULFUR ISOTOPES
TRACER TECHNIQUES
TRANSFERASES
TRITIUM COMPOUNDS
TYROSINE
VERTEBRATES