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Merged Aude BERNHEIM requested to merge abernhei-main-patch-84869 into main
@@ -9,17 +9,25 @@ tableColumns:
Sensor: Unknown
Activator: Unknown
Effector: Nucleic acid degrading
contributors:
- Hugo Vaysset
- Aude Bernheim
relevantAbstracts:
- doi: 10.1016/j.cell.2023.01.026
- doi: 10.1016/j.cell.2023.01.012
- doi: 10.1126/science.aba0372
---
# RADAR
## Description
RADAR is comprised of two genes, encoding respectively for an adenosine triphosphatase (RdrA) and a divergent adenosine deaminase (RdrB) (1), which are in some cases associated with a small membrane protein (RdrC or D) (1).
RADAR was found to perform RNA editing of adenosine to inosine during phage infection. Editing sites are broadly distributed on the host transcriptome, which could prove deleterious to the host and explain the observed growth arrest of RADAR upon phage infection.
RADAR (Restriction by an Adenosine Deaminase Acting on RNA) is comprised of two genes, encoding respectively for an adenosine triphosphatase (RdrA) and a divergent adenosine deaminase (RdrB), which are in some cases associated with a small membrane protein (RdrC or D). They were first uncovered in a study exploring content of defense islands :ref{doi=10.1126/science.aba0372}.
## Molecular mechanism
RADAR mediates growth arrest upon infection and is therefore considered to be an Abortive infection system.
In the initial study describing RADAR, RADAR was found to perform RNA editing of adenosine to inosine during phage infection :ref{doi=10.1126/science.aba0372}. Editing sites were broadly distributed on the host transcriptome, which could prove deleterious leading to observed growth arrest of RADAR upon phage infection.
Further structural studies revealed potential different mechanism of actions :ref{doi=10.1016/j.cell.2023.01.026, 10.1016/j.cell.2023.01.012}. RdrA and RdrB assemble to form a giant 10 MDa complex. The RADAR defense system limits phage replication by catalyzing ATP deamination. Within this system, RdrB functions as an adenosine deaminase, leading to the buildup of ITP (Inosine Tri-Phosphate) and dITP. RdrA induces RdrB activity and potentially regulates the detection of phage infections.
## Example of genomic structure
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## Relevant abstracts
::relevant-abstracts
---
items:
- doi: 10.1126/science.aba0372
---
::
## References
1. Gao L, Altae-Tran H, Böhning F, et al. Diverse enzymatic activities mediate antiviral immunity in prokaryotes. *Science*. 2020;369(6507):1077-1084. doi:10.1126/science.aba0372