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A tetrameric complex of membrane proteins in the endoplasmic reticulum

Item Type:Article
Title:A tetrameric complex of membrane proteins in the endoplasmic reticulum
Creators Name:Hartmann, E., Goerlich, D., Kostka, S., Otto, A., Kraft, R., Knespel, S., Buerger, E., Rapoport, T.A. and Prehn, S.
Abstract:The translocation site (translocon), at which nascent polypeptides pass through the endoplasmic reticulum membrane, contains a component previously called 'signal sequence receptor' that is now renamed as 'translocon-associated protein' (TRAP). Two glycosylated subunits of the TRAP complex have been identified before (alpha and beta subunits). We now show that TRAP complex is actually comprised of four membrane proteins (alpha, beta, gamma, delta), present in a stoichiometric relation, which are genuine neighbours in intact microsomes. The amino acid sequences of the additional, non-glycosylated subunits were deduced from cloning of the corresponding cDNAs. The delta subunit spans the membrane only once and has its major portion, containing a disulfide bridge, at the lumenal side. The gamma subunit is predicted to span the membrane four times.
Keywords:Amino Acid Sequence, Base Sequence, Calcium-Binding Proteins, Cell Surface Receptors, Cytoplasmic and Nuclear Receptors, DNA, Endoplasmic Reticulum, Macromolecular Substances, Membrane Glycoproteins, Molecular Cloning, Molecular Sequence Data, Peptide Receptors, Animals, Dogs
Source:European Journal of Biochemistry
Publisher:Blackwell Publishing
Page Range:375-381
Date:1 June 1993
Official Publication:https://doi.org/10.1111/j.1432-1033.1993.tb17933.x
PubMed:View item in PubMed

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