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Abstract Multiple species within the order Hemiptera cause severe agricultural losses on a global scale. Aphids and whiteflies are of particular importance due to their role as vectors for hundreds of plant viruses, many of which enter the insect via the gut. To facilitate the identification of novel targets for disruption of plant virus transmission, we compared the relative abundance and composition of the gut plasma membrane proteomes of adultBemisia tabaci(Hemiptera: Aleyrodidae) andMyzus persicae(Hemiptera: Aphididae), representing the first study comparing the gut plasma membrane proteomes of two different insect species. Brush border membrane vesicles were prepared from dissected guts, and proteins extracted, identified and quantified from triplicate samples via timsTOF mass spectrometry. A total of 1699B. tabaciand 1175M. persicaeproteins were identified. Following bioinformatics analysis and manual curation, 151B. tabaciand 115M. persicaeproteins were predicted to localize to the plasma membrane of the gut microvilli. These proteins were further categorized based on molecular function and biological process according to Gene Ontology terms. The most abundant gut plasma membrane proteins were identified. The ten plasma membrane proteins that differed in abundance between the two insect species were associated with the terms “protein binding” and “viral processes.” In addition to providing insight into the gut physiology of hemipteran insects, these gut plasma membrane proteomes provide context for appropriate identification of plant virus receptors based on a combination of bioinformatic prediction and protein localization on the surface of the insect gut.
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Synthesis, insertion, and characterization of SARS-CoV-2 membrane protein within lipid bilayers
Throughout history, coronaviruses have posed challenges to both public health and the global economy; nevertheless, methods to combat them remain rudimentary, primarily due to the absence of experiments to understand the function of various viral components. Among these, membrane (M) proteins are one of the most elusive because of their small size and challenges with expression. Here, we report the development of an expression system to produce tens to hundreds of milligrams of M protein per liter ofEscherichia coliculture. These large yields render many previously inaccessible structural and biophysical experiments feasible. Using cryo–electron microscopy and atomic force microscopy, we image and characterize individual membrane-incorporated M protein dimers and discover membrane thinning in the vicinity, which we validated with molecular dynamics simulations. Our results suggest that the resulting line tension, along with predicted induction of local membrane curvature, could ultimately drive viral assembly and budding.
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- PAR ID:
- 10527284
- Publisher / Repository:
- American Association for the Advancement of Science
- Date Published:
- Journal Name:
- Science Advances
- Volume:
- 10
- Issue:
- 9
- ISSN:
- 2375-2548
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1126/sciadv.adm7030
