Evidence for a role of caveolin-1 in neurokinin-1 receptor plasma-membrane localization, efficient signaling, and interaction with β-arrestin 2

A fraction of the nuclear estrogen receptor α (ERα) is localized to the plasma membrane region of 17β-estradiol (E2) target cells. We previously reported that ERα is a palmitoylated protein. To gain insight into the molecular mechanism of ERα residence at the plasma membrane, we tested both the role of palmitoylation and the impact of E2 stimulation on ERα membrane localization. The cancer cell lines expressing transfected or endogenous human ERα (HeLa and HepG2, respectively) or the ERα nonpalmitoylable Cys447Ala mutant transfected in HeLa cells were used as experimental models. We found that palmitoylation of ERα enacts ERα association with the plasma membrane, interaction with the membrane protein caveolin-1, and nongenomic activities, including activation of signaling pathways and cell proliferation (i.e., ERK and AKT activation, cyclin D1 promoter activity, DNA synthesis). Moreover, E2 reduces both ERα palmitoylation and its interaction with caveolin-1, in a time- and dose-dependent manner. These data point to the physiological role of ERα palmitoylation in the receptor localization to the cell membrane and in the regulation of the E2-induced cell proliferation.

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Mutation of Hydrophobic Residues in the C-Terminal Domain of the Marburg Virus Matrix Protein VP40 Disrupts Trafficking to the Plasma Membrane

Viruses ◽

10.3390/v12040482 ◽

2020 ◽

Vol 12 (4) ◽

pp. 482 ◽

Cited By ~ 2

Author(s):

Kaveesha J. Wijesinghe ◽

Luke McVeigh ◽

Monica L. Husby ◽

Nisha Bhattarai ◽

Jia Ma ◽

...

Keyword(s):

Amino Acids ◽

Plasma Membrane ◽

Matrix Protein ◽

Marburg Virus ◽

Membrane Localization ◽

Hydrophobic Residues ◽

Plasma Membrane Localization ◽

Terminal Domain ◽

Loop Region

Marburg virus (MARV) is a lipid-enveloped negative sense single stranded RNA virus, which can cause a deadly hemorrhagic fever. MARV encodes seven proteins, including VP40 (mVP40), a matrix protein that interacts with the cytoplasmic leaflet of the host cell plasma membrane. VP40 traffics to the plasma membrane inner leaflet, where it assembles to facilitate the budding of viral particles. VP40 is a multifunctional protein that interacts with several host proteins and lipids to complete the viral replication cycle, but many of these host interactions remain unknown or are poorly characterized. In this study, we investigated the role of a hydrophobic loop region in the carboxy-terminal domain (CTD) of mVP40 that shares sequence similarity with the CTD of Ebola virus VP40 (eVP40). These conserved hydrophobic residues in eVP40 have been previously shown to be critical to plasma membrane localization and membrane insertion. An array of cellular experiments and confirmatory in vitro work strongly suggests proper orientation and hydrophobic residues (Phe281, Leu283, and Phe286) in the mVP40 CTD are critical to plasma membrane localization. In line with the different functions proposed for eVP40 and mVP40 CTD hydrophobic residues, molecular dynamics simulations demonstrate large flexibility of residues in the EBOV CTD whereas conserved mVP40 hydrophobic residues are more restricted in their flexibility. This study sheds further light on important amino acids and structural features in mVP40 required for its plasma membrane localization as well as differences in the functional role of CTD amino acids in eVP40 and mVP40.

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A Conserved Tryptophan in the Ebola Virus Matrix Protein C-Terminal Domain Is Required for Efficient Virus-Like Particle Formation

Pathogens ◽

10.3390/pathogens9050402 ◽

2020 ◽

Vol 9 (5) ◽

pp. 402 ◽

Cited By ~ 1

Author(s):

Kristen A. Johnson ◽

Rudramani Pokhrel ◽

Melissa R. Budicini ◽

Bernard S. Gerstman ◽

Prem P. Chapagain ◽

...

Keyword(s):

Plasma Membrane ◽

Matrix Protein ◽

Ebola Virus ◽

Membrane Localization ◽

Virus Like Particles ◽

Plasma Membrane Localization ◽

The Matrix ◽

Dynamics Simulations

The Ebola virus (EBOV) harbors seven genes, one of which is the matrix protein eVP40, a peripheral protein that is sufficient to induce the formation of virus-like particles from the host cell plasma membrane. eVP40 can form different structures to fulfil different functions during the viral life cycle, although the structural dynamics of eVP40 that warrant dimer, hexamer, and octamer formation are still poorly understood. eVP40 has two conserved Trp residues at positions 95 and 191. The role of Trp95 has been characterized in depth as it serves as an important residue in eVP40 oligomer formation. To gain insight into the functional role of Trp191 in eVP40, we prepared mutations of Trp191 (W191A or W191F) to determine the effects of mutation on eVP40 plasma membrane localization and budding as well as eVP40 oligomerization. These in vitro and cellular experiments were complemented by molecular dynamics simulations of the wild-type (WT) eVP40 structure versus that of W191A. Taken together, Trp is shown to be a critical amino acid at position 191 as mutation to Ala reduces the ability of VP40 to localize to the plasma membrane inner leaflet and form new virus-like particles. Further, mutation of Trp191 to Ala or Phe shifted the in vitro equilibrium to the octamer form by destabilizing Trp191 interactions with nearby residues. This study has shed new light on the importance of interdomain interactions in stability of the eVP40 structure and the critical nature of timing of eVP40 oligomerization for plasma membrane localization and viral budding.

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Caveolin-1 Contributes to Assembly of Store-operated Ca2+Influx Channels by Regulating Plasma Membrane Localization of TRPC1

Journal of Biological Chemistry ◽

10.1074/jbc.m301118200 ◽

2003 ◽

Vol 278 (29) ◽

pp. 27208-27215 ◽

Cited By ~ 164

Author(s):

So-ching W. Brazer ◽

Brij B. Singh ◽

Xibao Liu ◽

William Swaim ◽

Indu S. Ambudkar

Keyword(s):

Plasma Membrane ◽

Membrane Localization ◽

Caveolin 1 ◽

Plasma Membrane Localization

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Role of Phosphatidylinositol 4,5-Bisphosphate in Regulating EHD2 Plasma Membrane Localization

PLoS ONE ◽

10.1371/journal.pone.0074519 ◽

2013 ◽

Vol 8 (9) ◽

pp. e74519 ◽

Cited By ~ 16

Author(s):

Laura C. Simone ◽

Steve Caplan ◽

Naava Naslavsky

Keyword(s):

Plasma Membrane ◽

Membrane Localization ◽

Plasma Membrane Localization

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Plasma Membrane Localization of TRPC Channels: Role of Caveolar Lipid Rafts

Mammalian TRP Channels as Molecular Targets - Novartis Foundation Symposia ◽

10.1002/0470862580.ch5 ◽

2008 ◽

pp. 63-74 ◽

Cited By ~ 42

Author(s):

Indu S. Ambudkar ◽

So-Ching Brazer ◽

Xibao Liu ◽

Timothy Lockwich ◽

Brij Singh

Keyword(s):

Plasma Membrane ◽

Lipid Rafts ◽

Membrane Localization ◽

Trpc Channels ◽

Plasma Membrane Localization

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The Role of Palmitoylation in Signalling, Cellular Trafficking and Plasma Membrane Localization of Protease-Activated Receptor-2

PLoS ONE ◽

10.1371/journal.pone.0028018 ◽

2011 ◽

Vol 6 (11) ◽

pp. e28018 ◽

Cited By ~ 33

Author(s):

Mark N. Adams ◽

Melinda E. Christensen ◽

Yaowu He ◽

Nigel J. Waterhouse ◽

John D. Hooper

Keyword(s):

Plasma Membrane ◽

Membrane Localization ◽

Cellular Trafficking ◽

Plasma Membrane Localization ◽

Protease Activated Receptor 2

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Mutation of Hydrophobic Residues in the C-Terminal Domain of the Marburg Virus Matrix Protein VP40 Disrupts Trafficking to the Plasma Membrane

10.20944/preprints202002.0467.v1 ◽

2020 ◽

Author(s):

Kaveesha J. Wijesinghe ◽

Luke McVeigh ◽

Monica L. Husby ◽

Nisha Bhattarai ◽

Jia Ma ◽

...

Keyword(s):

Amino Acids ◽

Plasma Membrane ◽

Matrix Protein ◽

Marburg Virus ◽

Membrane Localization ◽

Hydrophobic Residues ◽

Plasma Membrane Localization ◽

Terminal Domain ◽

Loop Region

Marburg virus (MARV) is a lipid-enveloped negative sense single stranded RNA virus, which can cause a deadly hemorrhagic fever. MARV encodes seven proteins, including VP40 (mVP40), a matrix protein that interacts with the cytoplasmic leaflet of the host cell plasma membrane. VP40 traffics to the plasma membrane inner leaflet, where it assembles to facilitate the budding of viral particles. VP40 is a multifunctional protein that interacts with several host proteins and lipids to complete the viral replication cycle, but many of these host-interactions remain unknown or are poorly characterized. In this study, we investigated the role of a hydrophobic loop region in the carboxy-terminal domain (CTD) of mVP40 that shares sequence similarity with the CTD of Ebola virus VP40 (eVP40). These conserved hydrophobic residues in eVP40 have been previously shown to be critical to plasma membrane localization and membrane insertion. An array of cellular experiments and confirmatory in vitro work strongly suggests proper orientation and hydrophobic residues (Phe281, Leu283, and Phe286) in the mVP40 CTD are critical to plasma membrane localization. In line with the different functions proposed for eVP40 and mVP40 CTD hydrophobic residues, molecular dynamics simulations demonstrate large flexibility of residues in the EBOV CTD whereas conserved mVP40 hydrophobic residues are more restricted in their flexibility. This study sheds further light on important amino acids and structural features in mVP40 required for its plasma membrane localization as well as differences in the functional role of CTD amino acids in eVP40 and mVP40.

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