URF13, a maize mitochondrial pore-forming protein, is oligomeric and has a mixed orientation in Escherichia coli plasma membranes.

Journal Article

URF13, an inner mitochondrial membrane protein of the maize Texas male-sterile cytoplasm (cms-T), has one orientation in the inner membrane of maize mitochondria but two topological orientations in the plasma membrane when expressed in Escherichia coli. Antibodies specific for the carboxyl terminus of URF13 and for an amino-terminal tag fused to URF13 in E. coli were used to determine the location of each end of the protein following protease treatments of right-side-out and inside-out vesicles derived from cms-T mitochondria and the E. coli plasma membrane. Cross-linking studies indicate that a portion of the URF13 population in mitochondria and E. coli exists in membranes in an oligomeric state and, in combination with proteolysis studies, show that individual subunits within a given multimer have the same orientation. A three-membrane-spanning helical model for URF13 topology is presented.

Full Text

Duke Authors

Cited Authors

  • Korth, KL; Kaspi, CI; Siedow, JN; Levings, CS

Published Date

  • December 1, 1991

Published In

Volume / Issue

  • 88 / 23

Start / End Page

  • 10865 - 10869

PubMed ID

  • 1961757

International Standard Serial Number (ISSN)

  • 0027-8424

Language

  • eng

Conference Location

  • United States