Short cytoplasmic sequences serve as retention signals for transmembrane proteins in the endoplasmic reticulum.
The adenoviral transmembrane E3/19K glycoprotein is a resident of the endoplasmic reticulum. Here we show that the last six amino acid residues of the 15-membered cytoplasmic tail are necessary and sufficient for the ER retention. These residues can be transplanted onto the cytoplasmic tail of other membrane-bound proteins such that ER residency is conferred. Deletion analysis demonstrated that no single amino acid residue is responsible for the retention. The identified structural motif must occupy the extreme COOH-terminal position to be functional. An endogenous transmembrane ER protein, UDP-glucuronosyltransferase, also contains a retention signal in its cytoplasmic tail. We suggest that short linear sequences occupying the extreme COOH-terminal position of transmembrane ER proteins serve as retention signals.
Nilsson
T
T
Department of Immunology, Research Institute of Scripps Clinic, La Jolla, California 92037.
Jackson
M
M
Peterson
P A
PA
D017503:Adenovirus E3 Proteins; D000595:Amino Acid Sequence; D000945:Antigens, Differentiation, T-Lymphocyte / Q000378:metabolism; D016827:CD8 Antigens; D002451:Cell Compartmentation; D003001:Cloning, Molecular; D004252:DNA Mutational Analysis; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D014453:Glucuronosyltransferase / Q000378:metabolism; D066298:In Vitro Techniques; D007425:Intracellular Membranes / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism* / Q000648:ultrastructure; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013329:Structure-Activity Relationship; D014764:Viral Proteins / Q000502:physiology*
D017503:Adenovirus E3 Proteins; D000945:Antigens, Differentiation, T-Lymphocyte; D016827:CD8 Antigens; D008565:Membrane Proteins; D011993:Recombinant Fusion Proteins; D014764:Viral Proteins; D014453:Glucuronosyltransferase