Role of novel surface glycosylated RNA molecules (glycoRNA) in infection biology

The 2024/25 application process is now CLOSED

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Abstract

The cell surface glycocalyx is a complex and dynamic structure formed by proteins and lipids bound to the plasma membrane. These are usually glycosylated (glycoproteins and glycolipids, and play important roles in cell physiology but also in infection biology as interactive receptors for pathogens or defence molecules. Recently in 2021, a new type of cell surface molecule has been discovered, formed by a main RNA body modified by the addition of a glycan, and hence named glycoRNA. To date, the biological functions of glycoRNA remain unknown. This project aims at elucidating the role of glycoRNAs in infection using multiple viral (e.g., SARS-CoV-2, dengue, Zika virus) and parasitic (Trypanosoma, Leishmania, Plasmodium, filarial parasites) infection systems. The project will identify potential roles of glycoRNA in pathogen interaction, attachment and/or invasion of host cells, as well as changes in glycoRNA composition and abundance induced by infection, with the ultimate goal of exploiting glycoRNAs to develop new therapeutic strategies to tackle infection. This highly interdisciplinary project requires advanced cell and molecular biology methods to edit and knock out host glycoRNA genes using CRISPR-Cas9/13, as well as virus/parasite genome editing, and metabolic labelling and click/bioorthogonal chemistry to label glycoRNA for its detection using blotting-based methods. It also involves state-of-the-art confocal and high content microscopy to image glycoRNA using immunostaining and aptamer and RNA in situ hybridization-mediated proximity ligation assay (ARPLA), and the use of transcriptomics and glycomics to fully identify and characterise glycoRNAs. In summary, the study of glycoRNA presents a huge potential for basic and translational discoveries in infection biology

Where does the project lie on the Translational Pathway?

T1 – Basic Research

Expected Outputs

The project is expected to deliver high-impact peer-reviewed publications (one for general findings, other individual ones for specific diseases/pathogens). It is also expected to generate data to support multiple follow up grant applications and fellowships. This project has the potential for huge impact in basic and translational science due to the novelty of glycoRNA as an unknown type of surface molecule.

Training Opportunities

The student will learn a broad range of advanced methods in molecular biology (cloning and mutagenesis), biochemistry (bioorthogonal click chemistry), imaging (confocal and high content imaging), and cell biology (several viral and parasitic infection systems). The candidate will attend several courses to perfect or train on new methods required, and international conferences to present their results. The student will also have the opportunity of a placement in a collaborator lab.

Skills Required

Not many skills and experience are essential, although experience in any standard molecular biology, biochemistry and imaging methods is desirable. The PhD candidate will be taught and learn all methods required, as well as develop and optimise new ones. More important and desirables are aptitudes like motivation, resilience, and critical thinking.

Key Publications associated with this project

Flynn RA, Pedram K, Malaker SA, Batista PJ, Smith BAH, Johnson AG, George BM, Majzoub K, Villalta PW, Carette JE, Bertozzi CR. Small RNAs are modified with N-glycans and displayed on the surface of living cells. Cell. 2021 Jun 10;184(12):3109-3124.e22. doi: 10.1016/j.cell.2021.04.023. Epub 2021 May 17. PMID: 34004145; PMCID: PMC9097497.

Ma Y, Guo W, Mou Q, Shao X, Lyu M, Garcia V, Kong L, Lewis W, Ward C, Yang Z, Pan X, Yi SS, Lu Y. Spatial imaging of glycoRNA in single cells with ARPLA. Nat Biotechnol. 2023 May 22. doi: 10.1038/s41587-023-01801-z. Epub ahead of print. PMID: 37217750.

Helena Hemberger, Peiyuan Chai, Charlotta G. Lebedenko, Reese M. Caldwell, Benson M. George, Ryan A. Flynn.  Rapid and sensitive detection of native glycoRNAs. bioRxiv 2023.02.26.530106; doi: https://doi.org/10.1101/2023.02.26.530106

Chai P, Lebedenko CG, Flynn RA. RNA Crossing Membranes: Systems and Mechanisms Contextualizing Extracellular RNA and Cell Surface GlycoRNAs. Annu Rev Genomics Hum Genet. 2023 Aug 25;24:85-107. doi: 10.1146/annurev-genom-101722-101224. Epub 2023 Apr 17. PMID: 37068783.