trim-21 promotes proteasomal degradation of CED-1 for apoptotic cell clearance in C. elegans
Abstract
The phagocytic receptor CED-1 mediates apoptotic cell recognition by phagocytic cells, enabling cell corpse clearance in Caenorhabditis elegans. Whether appropriate levels of CED-1 are maintained for executing the engulfment function remains unknown. Here, we identified the C. elegans E3 ubiquitin ligase tripartite motif containing-21 (TRIM-21) as a component of the CED-1 pathway for apoptotic cell clearance. When the NPXY motif of CED-1 was bound to the adaptor protein CED-6 or the YXXL motif of CED-1 was phosphorylated by tyrosine kinase SRC-1 and subsequently bound to the adaptor protein NCK-1 containing the SH2 domain, TRIM-21 functioned in conjunction with UBC-21 to catalyze K48-linked poly-ubiquitination on CED-1, targeting it for proteasomal degradation. In the absence of TRIM-21, CED-1 accumulated post-translationally and drove cell corpse degradation defects, as evidenced by direct binding to VHA-10. These findings reveal a unique mechanism for the maintenance of appropriate levels of CED-1 to regulate apoptotic cell clearance.
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All data generated or analysed during this study are included in the manuscript and supporting file.
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Author details
Funding
National Natural Science Foundation of China (91954114)
- Hui Xiao
National Natural Science Foundation of China (31871387)
- Hui Xiao
the Innovative Research Team for the Central Universities (GK202001004)
- Hui Xiao
Natural Science Foundation Youth Project of Shaanxi Province (2022JQ208)
- Qian Zheng
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Yuan 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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