title: Parts-based assembly of synthetic transmembrane proteins in mammalian cells.
abstract: Transmembrane proteins span cellular membranes such as the plasma membrane and endoplasmic reticulum (ER) membrane to mediate inter- and intracellular interactions. An N-terminal signal peptide and transmembrane helices facilitate recruitment to the ER and integration into the membrane, respectively. Using a parts-based assembly approach in this study, we confirm that the minimum requirement to create a transmembrane protein is indeed only a transmembrane helix (TM). When transfected in mammalian cells, our fusion proteins in the schematic form X-TM-Y were localized to vesicles, the golgi apparatus, the nuclear envelope, or the endoplasmic reticulum, consistent with ER targeting. Further studies to determine orientation showed that X was facing the cytoplasm, and Y the lumen. Lastly, in our fusion proteins with an N-terminal TM, the TM effectively reversed the orientation of X and Y. This knowledge can be applied to the parts-based engineering of synthetic transmembrane proteins with varied functions and biological applications.
authors: Seema
authors: S
authors: Nagaraj
authors: Stanley
authors: S
authors: Wong
authors: Kevin
authors: K
authors: Truong
mesh_terms: D000818:Animals; D019556:COS Cells; D002522:Chlorocebus aethiops; D004721:Endoplasmic Reticulum / Q000378:metabolism; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015202:Protein Engineering / Q000379:methods*; D021382:Protein Sorting Signals / Q000235:genetics; D017433:Protein Structure, Secondary; D021381:Protein Transport; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D058615:Synthetic Biology / Q000379:methods*; D014162:Transfection
chemical_list: D008565:Membrane Proteins; D021382:Protein Sorting Signals; D011993:Recombinant Fusion Proteins