Dataset Information


An investigation of the transverse topology of bilirubin UDP-glucuronosyltransferase in rat hepatic endoplasmic reticulum.

ABSTRACT: Bilirubin UDP-glucuronosyltransferase (UDPGT) activity in sealed hepatic microsomes from clofibrate-treated rats was highly latent and was fully expressed by disruption of vesicles with detergents. Antibodies raised against purified bilirubin UDPGT were used to study the transmembrane orientation of the protein to provide a molecular understanding of the UDPGT latency. Immunoblot analysis of sealed microsomes, and microsomes after treatment with proteinases, showed that only a small portion of the protein resides on the cytoplasmic side of the microsomal vesicles. Treatment of microsomes with sodium deoxycholate allowed subtilisin and proteinase K to cleave the transferase, causing loss of activity and the release of smaller immunodetectable peptides. Treatment of the purified bilirubin UDPGT with peptide N-glycosidase F indicated that the enzyme was a glycoprotein. A working model of the transmembrane topology of bilirubin UDPGT is described.


PROVIDER: S-EPMC1138556 | BioStudies | 1989-01-01

REPOSITORIES: biostudies

Similar Datasets

1992-01-01 | S-EPMC1132655 | BioStudies
1995-01-01 | S-EPMC1136259 | BioStudies
1997-01-01 | S-EPMC1218366 | BioStudies
1991-01-01 | S-EPMC1150023 | BioStudies
1989-01-01 | S-EPMC1138569 | BioStudies
1982-01-01 | S-EPMC1163694 | BioStudies
1984-01-01 | S-EPMC1144319 | BioStudies
1987-01-01 | S-EPMC1148495 | BioStudies
1991-01-01 | S-EPMC1151454 | BioStudies
2005-01-01 | S-EPMC1316310 | BioStudies