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- Pines, A, et al.
(författare)
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PARP1 promotes nucleotide excision repair through DDB2 stabilization and recruitment of ALC1
- 2012
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Ingår i: The Journal of cell biology. - : Rockefeller University Press. - 1540-8140 .- 0021-9525. ; 199:2, s. 235-249
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Tidskriftsartikel (refereegranskat)abstract
- The WD40-repeat protein DDB2 is essential for efficient recognition and subsequent removal of ultraviolet (UV)-induced DNA lesions by nucleotide excision repair (NER). However, how DDB2 promotes NER in chromatin is poorly understood. Here, we identify poly(ADP-ribose) polymerase 1 (PARP1) as a novel DDB2-associated factor. We demonstrate that DDB2 facilitated poly(ADP-ribosyl)ation of UV-damaged chromatin through the activity of PARP1, resulting in the recruitment of the chromatin-remodeling enzyme ALC1. Depletion of ALC1 rendered cells sensitive to UV and impaired repair of UV-induced DNA lesions. Additionally, DDB2 itself was targeted by poly(ADP-ribosyl)ation, resulting in increased protein stability and a prolonged chromatin retention time. Our in vitro and in vivo data support a model in which poly(ADP-ribosyl)ation of DDB2 suppresses DDB2 ubiquitylation and outline a molecular mechanism for PARP1-mediated regulation of NER through DDB2 stabilization and recruitment of the chromatin remodeler ALC1.
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| 2. |
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| 3. |
- Irazoki, Oihane, et al.
(författare)
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D-amino acids signal a stress-dependent run-away response in Vibrio cholerae
- 2023
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Ingår i: Nature Microbiology. - : Springer Nature. - 2058-5276. ; 8:8, s. 1549-1560
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Tidskriftsartikel (refereegranskat)abstract
- To explore favourable niches while avoiding threats, many bacteria use a chemotaxis navigation system. Despite decades of studies on chemotaxis, most signals and sensory proteins are still unknown. Many bacterial species release d-amino acids to the environment; however, their function remains largely unrecognized. Here we reveal that d-arginine and d-lysine are chemotactic repellent signals for the cholera pathogen Vibrio cholerae. These d-amino acids are sensed by a single chemoreceptor MCPDRK co-transcribed with the racemase enzyme that synthesizes them under the control of the stress-response sigma factor RpoS. Structural characterization of this chemoreceptor bound to either d-arginine or d-lysine allowed us to pinpoint the residues defining its specificity. Interestingly, the specificity for these d-amino acids appears to be restricted to those MCPDRK orthologues transcriptionally linked to the racemase. Our results suggest that d-amino acids can shape the biodiversity and structure of complex microbial communities under adverse conditions.
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