title: Snorkel: an epitope tagging system for measuring the surface expression of membrane proteins.
abstract: Tags are widely used to monitor a protein's expression level, interactions, protein trafficking, and localization. Membrane proteins are often tagged in their extracellular domains to allow discrimination between protein in the plasma membrane from that in internal pools. Multipass membrane proteins offer special challenges for inserting a tag since the extracellular regions are often composed of small loops and thus inserting an epitope tag risks perturbing the structure, function, or location of the membrane protein. We have developed a novel tagging system called snorkel where a transmembrane domain followed by a tag is appended to the cytoplasmic C-terminus of the membrane protein. In this way the tag is displayed extracellularly, but structurally separate from the membrane protein. We have tested the snorkel tag system on a diverse panel of membrane proteins including GPCRs and ion channels and demonstrated that it reliably allows for monitoring of the surface expression.
authors.affiliation: SDIX, Newark, Delaware, United States of America.
authors.forename: Michael
authors.initials: M
authors.lastname: Brown
authors.forename: Lewis J
authors.initials: LJ
authors.lastname: Stafford
authors.forename: Dale
authors.initials: D
authors.lastname: Onisk
authors.forename: Tony
authors.initials: T
authors.lastname: Joaquim
authors.forename: Alhagie
authors.initials: A
authors.lastname: Tobb
authors.forename: Larissa
authors.initials: L
authors.lastname: Goldman
authors.forename: David
authors.initials: D
authors.lastname: Fancy
authors.forename: James
authors.initials: J
authors.lastname: Stave
authors.forename: Ross
authors.initials: R
authors.lastname: Chambers
mesh_terms: D000595:Amino Acid Sequence; D000939:Epitopes / Q000737:chemistry / Q000378:metabolism*; D005110:Extracellular Space / Q000378:metabolism; D005786:Gene Expression Regulation; D057809:HEK293 Cells; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D013194:Staining and Labeling / Q000379:methods*
chemical_list: D000939:Epitopes; D008565:Membrane Proteins
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