α-actinin accounts for the bioactivity of actin preparations in inducing STAT target genes in Drosophila melanogaster
- The Francis Crick Institute, United Kingdom
- University of Bristol, United Kingdom
- Instituto Gulbenkian de Ciência, Portugal
- Imperial College London, United Kingdom
- University of Edinburgh, United Kingdom
Abstract
Damage-associated molecular patterns (DAMPs) are molecules exposed or released by dead cells that trigger or modulate immunity and tissue repair. In vertebrates, the cytoskeletal component F-actin is a DAMP specifically recognised by DNGR-1, an innate immune receptor. Previously we suggested that actin is also a DAMP in Drosophila melanogaster by inducing STAT-dependent (Srinivasan et al., 2016). Here, we revise that conclusion and report that α-actinin is far more potent than actin at inducing the same STAT response and can be found in trace amounts in actin preparations. Recombinant expression of actin or α-actinin in bacteria demonstrated that only α-actinin could drive the expression of STAT target genes in Drosophila. The response to injected α-actinin required the same signalling cascade that we had identified in our previous work using actin preparations. Taken together, these data indicate that α-actinin rather than actin drives STAT activation when injected into Drosophila.
Data availability
Data generated or analysed during this study are included in the manuscript. Mass spectrometry data were uploaded as supporting file.
Article and author information
Author details
Caetano Reis e Sousa
Funding
Francis Crick Institute (FC001136)
- Caetano Reis e Sousa
Wellcome Trust (WT106973MA)
- Caetano Reis e Sousa
Federation of European Biochemical Societies
- Conor M Henry
Fundação para a Ciencia e Tecnologia (PTDC/BEX- GMG/3128/2014)
- Luis Teixeira
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Gordon et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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α-actinin accounts for the bioactivity of actin preparations in inducing STAT target genes in Drosophila melanogaster
eLife 7:e38636.
https://doi.org/10.7554/eLife.38636
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