LearnCoil-VMF: computational evidence for coiled-coil-like motifs in many viral membrane-fusion proteins

The advancement of precision medicine critically depends on the robustness and specificity of the carriers used for the targeted delivery of effector molecules in the human body. Numerous nanocarriers have been explored in vivo, to ensure the precise delivery of molecular cargos via tissue-specific targeting, including the endocrine part of the pancreas, thyroid, and adrenal glands. However, even after reaching the target organ, the cargo-carrying vehicle needs to enter the cell and then escape lysosomal destruction. Most artificial nanocarriers suffer from intrinsic limitations that prevent them from completing the specific delivery of the cargo. In this respect, extracellular vesicles (EVs) seem to be the natural tool for payload delivery due to their versatility and low toxicity. However, EV-mediated delivery is not selective and is usually short-ranged. By inserting the viral membrane fusion proteins into exosomes, it is possible to increase the efficiency of membrane recognition and also ease the process of membrane fusion. This review describes the molecular details of the viral-assisted interaction between the target cell and EVs. We also discuss the question of the usability of viral fusion proteins in developing extracellular vesicle-based nanocarriers with a higher efficacy of payload delivery. Finally, this review specifically highlights the role of Gag and RNA binding proteins in RNA sorting into EVs.

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The Many Mechanisms of Viral Membrane Fusion Proteins

Current Topics in Microbiology and Immunology - Membrane Trafficking in Viral Replication ◽

10.1007/3-540-26764-6_2 ◽

2004 ◽

pp. 25-66 ◽

Cited By ~ 70

Author(s):

L. J. Earp ◽

S. E. Delos ◽

H. E. Park ◽

J. M. White

Keyword(s):

Membrane Fusion ◽

Fusion Proteins ◽

Viral Membrane ◽

The Many ◽

Membrane Fusion Proteins ◽

Viral Membrane Fusion

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Viral Membrane Fusion Proteins and RNA Sorting Mechanisms for the Molecular Delivery by Exosomes

10.20944/preprints202110.0130.v1 ◽

2021 ◽

Author(s):

Ilya Zubarev ◽

Dmitry Vladimirtsev ◽

Maria Vorontsova ◽

Igor Blatov ◽

Konstantin Shevchenko ◽

...

Keyword(s):

Membrane Fusion ◽

Extracellular Vesicles ◽

Targeted Delivery ◽

Fusion Proteins ◽

Rna Binding ◽

Rna Binding Proteins ◽

Viral Fusion ◽

Viral Membrane ◽

Membrane Fusion Proteins ◽

Viral Membrane Fusion

The advancement of precision medicine critically depends on the robustness and specificity of the carriers used for the targeted delivery of effector molecules in the human body. Numerous nanocarriers have been explored in vivo, to ensure the precise delivery of molecular cargos via tissue-specific targeting, including the endocrine part of the pancreas, thyroid, and adrenal glands. However, even after reaching the target organ, the cargo-carrying vehicle needs to enter the cell and then escape from lysosomal destruction. Most of artificial nanocarriers suffer from intrinsic limitations that either prevent them from completing the specific delivery of the cargo. In this respect, extracellular vesicles (EVs) seem to be the natural tool for payload delivery due to their versatility and low toxicity. However, EV-mediated delivery is not selective and usually short-ranged. By inserting the viral membrane fusion proteins into exosomes, it is possible to increase the efficiency of membrane recognition and also ease the process of membrane fusion. This review describes the molecular details of the viral-assisted interaction between the target cell and extracellular vesicles. We also discuss the question of the usability of viral fusion proteins in developing extracellular vesicle-based nanocarriers with higher efficacy of payload delivery. Finally, this review specifically highlights the role of Gag and RNA binding proteins in RNA sorting into extracellular vesicles.

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Fusogenic Reoviruses and Their Fusion-Associated Small Transmembrane (FAST) Proteins

Annual Review of Virology ◽

10.1146/annurev-virology-092818-015523 ◽

2019 ◽

Vol 6 (1) ◽

pp. 341-363 ◽

Cited By ~ 9

Author(s):

Roy Duncan

Keyword(s):

Membrane Fusion ◽

Fusion Proteins ◽

Syncytium Formation ◽

Nonstructural Proteins ◽

Enveloped Virus ◽

Fast Proteins ◽

Nonenveloped Virus ◽

Functional Features ◽

Membrane Fusion Proteins ◽

Viral Membrane Fusion

With no limiting membrane surrounding virions, nonenveloped viruses have no need for membrane fusion to gain access to intracellular replication compartments. Consequently, nonenveloped viruses do not encode membrane fusion proteins. The only exception to this dogma is the fusogenic reoviruses that encode fusion-associated small transmembrane (FAST) proteins that induce syncytium formation. FAST proteins are the smallest viral membrane fusion proteins and, unlike their enveloped virus counterparts, are nonstructural proteins that evolved specifically to induce cell-to-cell, not virus-cell, membrane fusion. This distinct evolutionary imperative is reflected in structural and functional features that distinguish this singular family of viral fusogens from all other protein fusogens. These rudimentary fusogens comprise specific combinations of different membrane effector motifs assembled into small, modular membrane fusogens. FAST proteins offer a minimalist model to better understand the ubiquitous process of protein-mediated membrane fusion and to reveal novel mechanisms of nonenveloped virus dissemination that contribute to virulence.

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Measurement of membrane fusion activity from viral membrane fusion proteins based on a fusion-dependent promoter induction system in insect cells

Journal of General Virology ◽

10.1099/0022-1317-82-10-2519 ◽

2001 ◽

Vol 82 (10) ◽

pp. 2519-2529 ◽

Cited By ~ 2

Author(s):

J. M. Slack ◽

G. W. Blissard

Keyword(s):

Membrane Fusion ◽

Cell Fusion ◽

Insect Cells ◽

Syncytium Formation ◽

Fusion Activity ◽

Viral Membrane ◽

Fusion Domain ◽

Membrane Fusion Proteins ◽

Viral Membrane Fusion ◽

Egfp Fluorescence

A number of viral membrane fusion proteins can be expressed alone on the surface of host cells, and then triggered to induce cell-to-cell fusion or syncytium formation. Although rapid and easily observed, syncytium formation is not easily quantified and differences in fusion activity are not easily distinguished or measured. To address this problem, we developed a rapid and quantitative cell-to-cell fusion system that is useful for comparative analysis and may be suitable for high throughput screening. In this system, expression of a reporter protein, enhanced green fluorescent protein (EGFP), is dependent on cell-to-cell fusion. Spodoptera frugiperda (Sf9) insect cells expressing a chimeric Lac repressor-IE1 protein were fused to Sf9 cells containing an EGFP reporter construct under the control of a responsive lac operator-containing promoter. Membrane fusion efficiency was measured from the resulting EGFP fluorescence activity. Sf9 cells expressing the Orgyia pseudotsugata multicapsid nucleopolyhedrovirus (OpMNPV) GP64 envelope fusion protein were used as a model to test this fusion assay. Subtle changes in fusion activities of GP64 proteins containing single amino acid substitutions in a putative membrane fusion domain were distinguished, and decreases in EGFP fluorescence corresponded to decreases in the hydrophobicity in the small putative membrane fusion domain.

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