DIM · Decoding ISGylation events in Macrophages
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2018-05-01 → 2020-05-31
- EU contribution
- €183,455
- Participants
- 1
- Scheme
- MSCA-IF
Lines connect the coordinator with its partners.
Results in brief
Decoding ISGylation events in Macrophages
What is the problem/issue being addressed? Innate immunity represent the first defense barrier against pathogens. The main player in this defense mechanism is a subfamily of white blood cells, the macrophages, which can recognize, isolate and eliminate foreign pathogens such as bacteria. The protein ISG15 has been identified as a main regulator of this process. For example, patient lacking a functional gene for ISG15 are more susceptible to tuberculosis infection. However, we currently do not know the role of ISG15 in this process. In order to understand the function of ISG15, I proposed to develop analytical strategies for identifying the substrates of ISG15 in mouse and human cells using state of the art mass spectrometers. Why is it important for society? ISG15 is part of a larger family of proteins termed ubiquitin like modifiers (UBL). Different UBL, as well as their regulation machinery, represent important drug targets for various diseases such as Alzheimer disease or cancer. Understanding the role of ISG15 could lead to spin off projects that would allow for the development of new drugs against similar diseases. On the long term, it would also allow for developing new drugs against virulent bacteria such as Listeria monocytogenes or Mycobacterium tuberculosis. What are the overall objectives? My project was divided into three main objectives (1) Developing new tools and strategies to identify ISG15 substrates in mice (2) Using these tools to identify the role of ISG15 in macrophages (3) Transferring and validating this knowledge to human cells (after the 2 years fellowship)
Data: CORDIS, © European Union
Project objective
The protein interferon stimulated gene 15 (ISG15) is a highly conserved ubiquitin-like modifier important for innate immune responses in mammals. ISG15 is highly abundant in cell lysates and enriched on the phagosome of interferon-activated macrophages. In humans, lack of ISG15 leads to increased susceptibility to infection by mycobacterial pathogens that reside in the phagosome of macrophages. However, both ISGylation events and their role are poorly characterized. This is partly due to the lack of analytical tools for the identification of ISGylation sites in cells. Here, I propose to develop a proteomics strategy to enrich and identify ISG15 targets that will also allow characterizing the interplay of ISG15 with ubiquitin. I will apply this method to analyze how ISGylation changes in response to Salmonella infection in macrophages. In order to understand the mechanisms that lead to susceptibility to intracellular pathogens, I will further use these approaches to test how ISGylation affects phagosome biogenesis in macrophages. ISG15 substrates identified in my proteomics screens will be validated and further characterized using biochemical, cell biological and immunological tools. Altogether, this data will provide new functional insights how ISG15 regulates defense mechanisms against bacterial infections.
Original text from CORDIS.
Participants
- UNIVERSITY OF NEWCASTLE UPON TYNE · Newcastle Upon TyneCoordinatorUnited Kingdom
Links
Data: CORDIS, © European Union