Lipid rafts are membrane microdomains that function as platforms for signal transduction and membrane trafficking. Tyrosine kinase interacting protein (Tip) of T lymphotropic Herpesvirus saimiri (HVS) is targeted to lipid rafts in T cells and downregulates TCR and CD4 surface expression. Here, we report that the membrane-proximal amphipathic helix preceding Tip's transmembrane (TM) domain mediates lipid raft localization and membrane deformation. In turn, this motif directs Tip's lysosomal trafficking and selective TCR downregulation. The amphipathic helix binds to the negatively charged lipids and induces liposome tubulation, the TM domain mediates oligomerization, and cooperation of the membrane-proximal helix with the TM domain is sufficient for localization to lipid rafts and lysosomal compartments, especially the mutivesicular bodies. These findings suggest that the membrane-proximal amphipathic helix and TM domain provide HVS Tip with the unique ability to deform the cellular membranes in lipid rafts and to downregulate TCRs potentially through MVB formation.
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http://dx.doi.org/10.1371/journal.ppat.1000209 | DOI Listing |
Eur J Med Chem
January 2025
Institute of Materia Medica, Chinese Academy of Medical Sciences, Peking Union Medical College, No. 1 Xian Nong Tan Street, Beijing, 100050, PR China; Key Laboratory of Preclinical Study for New Drugs of Gansu Province, School of Basic Medical Sciences & Research Unit of Peptide Science, Chinese Academy of Medical Sciences, 2019RU066, Lanzhou University, Lanzhou, 730000, PR China; Institute of Pharmaceutics, School of Pharmacy, 2019RU066, Lanzhou University, Lanzhou, 730000, PR China. Electronic address:
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Department of Experimental Pathology, Federal University of São João del-Rei, Divinópolis 36301-158, Brazil.
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School of Biomedical Sciences, The University of Hong Kong, Pokfulam, Hong Kong.
C1orf115 has been identified in high-throughput screens as a regulator of multidrug resistance possibly mediated through an interaction with ATP-dependent membrane transporter ABCB1. Here we show that C1orf115 not only shares structural similarities with FACI/C11orf86 to interact with clathrin adaptors to undergo endocytosis, but also induces ABCA1 transcription to promote cholesterol efflux. C1orf115 consists of an N-terminal intrinsically disordered region and a C-terminal α-helix.
View Article and Find Full Text PDFbioRxiv
December 2024
T. C. Jenkins Department of Biophysics, The Johns Hopkins University, 3400 N. Charles St., Baltimore, Maryland 21218, USA.
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December 2024
Chemical and Biological Engineering Department, School of Engineering and Applied Sciences, State University of New York at Buffalo, Buffalo, NY, USA.
All-atom molecular dynamics (AAMD) is a computational technique that predicts the movement of particles based on the intermolecular forces acting on the system. It enables the study of biological systems at atomic detail, complements observations from experiments, and can help the selection of experimental targets. Here, we describe the applications of MD simulations to study the interaction between peripheral membrane proteins and lipid bilayers.
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