Flanking Residues Help Determine Whether a Hydrophobic Segment Adopts a Monotopic or Bitopic Topology in the Endoplasmic Reticulum Membrane
2011 (English)In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 286, no 28, 25284-25290 p.Article in journal (Refereed) Published
Proteins interacting with membranes via a single hydrophobic segment can be classified as either monotopic or bitopic. Here, we probe the topology of a membrane-attached enzyme, the epsilon isoform of human diacylglycerol kinase (DGK epsilon), when inserted into rough microsomes and compare it with the monotopic membrane protein mouse caveolin-1. In contrast to previous findings, the N-terminal hydrophobic stretch in DGK epsilon attains a bitopic rather than a monotopic topology in our experimental system. In addition, we find that charged flanking residues as well as proline residues embedded in the hydrophobic segment are important determinants of monotopic versus bitopic topology.
Place, publisher, year, edition, pages
2011. Vol. 286, no 28, 25284-25290 p.
IdentifiersURN: urn:nbn:se:su:diva-66583DOI: 10.1074/jbc.M111.244616ISI: 000292547900074OAI: oai:DiVA.org:su-66583DiVA: diva2:468596
authorCount :52011-12-212011-12-202011-12-21Bibliographically approved