Abstract
Multicellular animals rapidly clear dying cells from their bodies. Many of the pathways that mediate this cell removal are conserved through evolution. Here, we identify srgp-1 as a negative regulator of cell clearance in both Caenorhabditis elegans and mammalian cells. Loss of srgp-1 function results in improved engulfment of apoptotic cells, whereas srgp-1 overexpression inhibits apoptotic cell corpse removal. We show that SRGP-1 functions in engulfing cells and functions as a GTPase activating protein (GAP) for CED-10 (Rac1). Interestingly, loss of srgp-1 function promotes not only the clearance of already dead cells, but also the removal of cells that have been brought to the verge of death through sublethal apoptotic, necrotic or cytotoxic insults. In contrast, impaired engulfment allows damaged cells to escape clearance, which results in increased long-term survival. We propose that C. elegans uses the engulfment machinery as part of a primitive, but evolutionarily conserved, survey mechanism that identifies and removes unfit cells within a tissue.
This is a preview of subscription content, access via your institution
Relevant articles
Open Access articles citing this article.
-
Dynein links engulfment and execution of apoptosis via CED-4/Apaf1 in C. elegans
Cell Death & Disease Open Access 27 September 2018
-
SRGAP1, a crucial target of miR-340 and miR-124, functions as a potential oncogene in gastric tumorigenesis
Oncogene Open Access 13 December 2017
-
Both the apoptotic suicide pathway and phagocytosis are required for a programmed cell death in Caenorhabditis elegans
BMC Biology Open Access 16 May 2016
Access options
Subscribe to this journal
Receive 12 print issues and online access
$209.00 per year
only $17.42 per issue
Rent or buy this article
Get just this article for as long as you need it
$39.95
Prices may be subject to local taxes which are calculated during checkout




References
Vaux, D. L. & Korsmeyer, S. J. Cell death in development. Cell 96, 245–254 (1999).
Debatin, K.M. Apoptosis pathways in cancer and cancer therapy. Cancer Immunol. Immunother. 53, 153–159 (2004).
Savill, J., Gregory, C. & Haslett, C. Eat me or die. Science 302, 1516–1517 (2003).
Fullard, J. F., Kale, A. & Baker, N. E. Clearance of apoptotic corpses. Apoptosis 14, 1029–1037 (2009).
Zhou, Z., Hartwieg, E. & Horvitz, H. R. CED-1 is a transmembrane receptor that mediates cell corpse engulfment in C. elegans. Cell 104, 43–56 (2001).
Wu, Y. C. & Horvitz, H. R. The C. elegans cell corpse engulfment gene ced-7 encodes a protein similar to ABC transporters. Cell 93, 951–960 (1998).
Yu, X., Odera, S., Chuang, C. H., Lu, N. & Zhou, Z. C. elegans dynamin mediates the signaling of phagocytic receptor CED-1 for the engulfment and degradation of apoptotic cells. Dev. Cell 10, 743–757 (2006).
Kinchen, J. M. et al. Two pathways converge at CED-10 to mediate actin rearrangement and corpse removal in C. elegans. Nature 434, 93–99 (2005).
Liu, Q. A. & Hengartner, M. O. Candidate adaptor protein CED-6 promotes the engulfment of apoptotic cells in C. elegans. Cell 93, 961–972 (1998).
Gumienny, T. L. et al. CED-12/ELMO, a novel member of the CrkII/Dock180/Rac pathway, is required for phagocytosis and cell migration. Cell 107, 27–41 (2001).
Wu, Y. C. & Horvitz, H. R. C. elegans phagocytosis and cell-migration protein CED-5 is similar to human DOCK180. Nature 392, 501–504 (1998).
deBakker, C. D. et al. Phagocytosis of apoptotic cells is regulated by a UNC-73/TRIO-MIG-2/RhoG signaling module and armadillo repeats of CED-12/ELMO. Curr. Biol. 14, 2208–2216 (2004).
Reddien, P. W. & Horvitz, H. R. CED-2/CrkII and CED-10/Rac control phagocytosis and cell migration in Caenorhabditis elegans. Nat. Cell Biol. 2, 131–136 (2000).
Akakura, S. et al. C-terminal SH3 domain of CrkII regulates the assembly and function of the DOCK180/ELMO Rac-GEF. J. Cell Physiol. 204, 344–351 (2005).
Tosello-Trampont, A. C. et al. Identification of two signaling submodules within the CrkII/ELMO/Dock180 pathway regulating engulfment of apoptotic cells. Cell Death Differ. 14, 963–972 (2007).
Hurwitz, M. E. et al. Abl kinase inhibits the engulfment of apoptotic cells in Caenorhabditis elegans. PLoS Biol. 7, e99 (2009).
Cabello, J. et al. The Wnt pathway controls cell death engulfment, spindle orientation, and migration through CED-10/Rac. PLoS Biol. 8, e1000297 (2010).
Hsu, T. Y. & Wu, Y. C. Engulfment of apoptotic cells in C. elegans is mediated by integrin α/SRC signaling. Curr. Biol. 20, 477–486 (2010).
Rual, J. F. et al. Toward improving Caenorhabditis elegans phenome mapping with an ORFeome-based RNAi library. Genome Res. 14, 2162–2168 (2004).
Kamath, R. S. & Ahringer, J. Genome-wide RNAi screening in Caenorhabditis elegans. Methods 30, 313–321 (2003).
Sulston, J. E., Schierenberg, E., White, J. G. & Thomson, J. N. The embryonic cell lineage of the nematode Caenorhabditis elegans. Dev. Biol. 100, 64–119 (1983).
Kinchen, J. & Ravichandran, K. Journey to the grave: signaling events regulating removal of apoptotic cells. J. Cell Sci. 120, 2143–2149 (2007).
Conradt, B. & Horvitz, H. R. The C. elegans protein EGL-1 is required for programmed cell death and interacts with the Bcl2like protein CED-9. Cell 93, 519–529 (1998).
Patel, F. B. et al. The WAVE/SCAR complex promotes polarized cell movements and actin enrichment in epithelia during C. elegans embryogenesis. Dev. Biol. 324, 297–309 (2008).
Barrett, T. et al. The structure of the GTPase-activating domain from p50rhoGAP. Nature 385, 458–461 (1997).
Park, D. et al. BAI1 is an engulfment receptor for apoptotic cells upstream of the ELMO/Dock180/Rac module. Nature 450, 430–434 (2007).
Zaidel-Bar, R. et al. The F-BAR domain of SRGP-1 facilitates cell-cell adhesion during C. elegans morphogenesis. J. Cell Biol. 191, 761–769 (2010).
Blom, N., Gammeltoft, S. & Brunak, S. Sequence and structure-based prediction of eukaryotic protein phosphorylation sites. J. Mol. Biol. 294, 1351–1362 (1999).
Suetsugu, S., Toyooka, K. & Senju, Y. Subcellular membrane curvature mediated by the BAR domain superfamily proteins. Semin. Cell Dev. Biol. 21, 340–349 (2010).
Henne, W. M. et al. FCHo proteins are nucleators of clathrin-mediated endocytosis. Science 328, 1281–1284 (2010).
Guerrier, S. et al. The F-BAR domain of srGAP2 induces membrane protrusions required for neuronal migration and morphogenesis. Cell 138, 990–1004 (2009).
Yang, Y., Lu, J., Rovnak, J., Quackenbush, S. L. & Lundquist, E. A. SWAN1, a Caenorhabditis elegans WD repeat protein of the AN11 family, is a negative regulator of Rac GTPase function. Genetics 174, 1917–1932 (2006).
Zou, W. et al. Caenorhabditis elegans myotubularin MTM-1 negatively regulates the engulfment of apoptotic cells. PLoS Genet. 5, e1000679 (2009).
Reddien, P. W., Cameron, S. & Horvitz, H. R. Phagocytosis promotes programmed cell death in C. elegans. Nature 412, 198–202 (2001).
Hoeppner, D. J., Hengartner, M. O. & Schnabel, R. Engulfment genes cooperate with ced-3 to promote cell death in Caenorhabditis elegans. Nature 412, 202–206 (2001).
Chung, S., Gumienny, T. L., Hengartner, M. O. & Driscoll, M. A common set of engulfment genes mediates removal of both apoptotic and necrotic cell corpses in C. elegans. Nat. Cell Biol. 2, 931–937 (2000).
Galvin, B. D., Kim, S. & Horvitz, H. R. Caenorhabditis elegans genes required for the engulfment of apoptotic corpses function in the cytotoxic cell deaths induced by mutations in lin-24 and lin-33. Genetics 179, 403–417 (2008).
Mano, I. & Driscoll, M. DEG/ENaC channels: a touchy superfamily that watches its salt. Bioessays 21, 568–578 (1999).
Zhang, W. et al. Intersubunit interactions between mutant DEG/ENaCs induce synthetic neurotoxicity. Cell Death Differ. 15, 1794–1803 (2008).
Li, W. & Baker, N. E. Engulfment is required for cell competition. Cell 129, 1215–1225 (2007).
Brenner, S. The genetics of Caenorhabditis elegans. Genetics 77, 71–94 (1974).
Sulston, J. E. & Horvitz, H. R. Post-embryonic cell lineages of the nematode, Caenorhabditis elegans. Dev. Biol. 56, 110–156 (1977).
Chomczynski, P. & Sacchi, N. Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chloroform extraction. Anal. Biochem. 162, 156–159 (1987).
Schnabel, R., Hutter, H., Moerman, D. & Schnabel, H. Assessing normal embryogenesis in Caenorhabditis elegans using a 4D microscope: variability of development and regional specification. Dev. Biol. 184, 234–265 (1997).
Tosello-Trampont, A.C., Nakada-Tsukui, K. & Ravichandran, K.S. Engulfment of apoptotic cells is negatively regulated by Rho-mediated signaling. J. Biol .Chem. 278, 49911–49919 (2003).
Kinchen, J. M. et al. A pathway for phagosome maturation during engulfment of apoptotic cells. Nat. Cell. Biol. 10, 556–566 (2008).
Elliott, M. R. et al. Unexpected requirement for ELMO1 in clearance of apoptotic germ cells in vivo. Nature 467, 333–337 (2010).
Acknowledgements
We thank the Hengartner lab members for comments and discussions, M. Weiss for statistical advice and M. Jovanovic for assistance with in vivo pulldown experiments. Some strains were supplied by the Caenorhabditis Genetic Center (CGC), the C. elegans knock-out consortium (Oklahoma, USA) and the National Bioresource Project (Japan). This work was supported by grants from the American Heart Association and American Cancer Society (to J.M.K.), the NIGMS/NIH (to K.S.R., a William Benter Senior Fellow of the American Asthma Foundation), the Junta de Castilla y León (grant CSI03A08), the Spanish Ministry of Science and Innovation (grant BFU2010-21794) and the Riojasalud Foundation (to J.C.), the Junta de Castilla y León (Grupo de Excelencia GR265) and the Spanish Ministry of Science and Innovation (grants BFU200801808 and Consolider CSD200700015 to S.M.), the NIH postdoctoral training grant GM078747 and the fellowship from the Machiah Foundation (to R.Z.-B.), the Swiss National Science Foundation, The Ernst Hadorn Foundation and the European Union (FP5 project APOCLEAR to M.O.H.).
Author information
Authors and Affiliations
Contributions
L.J.N., A.P.F. and R.Z.B. contributed to the generation of nematode transgenics and fluorescence microscopy studies. A.P.F. and L.J.N. conducted the unbiased screen and the epistasis experiments. J.C. performed the 4D microscopic analysis. J.M.K. performed the mammalian cell culture experiments. Z.M. and L.B.H. performed the pulldowns and the hydrolysis assays. L.J.N. performed the cell-killing assay and wrote the manuscript. A.P.F. and M.O.H. contributed to the data analysis, project planning and writing of the manuscript. All authors contributed to editing the manuscript.
Corresponding author
Ethics declarations
Competing interests
The authors declare no competing financial interests.
Supplementary information
Supplementary Information
Supplementary Information (PDF 2567 kb)
Rights and permissions
About this article
Cite this article
Neukomm, L., Frei, A., Cabello, J. et al. Loss of the RhoGAP SRGP-1 promotes the clearance of dead and injured cells in Caenorhabditis elegans. Nat Cell Biol 13, 79–86 (2011). https://doi.org/10.1038/ncb2138
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/ncb2138
This article is cited by
-
Dynein links engulfment and execution of apoptosis via CED-4/Apaf1 in C. elegans
Cell Death & Disease (2018)
-
SRGAP1, a crucial target of miR-340 and miR-124, functions as a potential oncogene in gastric tumorigenesis
Oncogene (2018)
-
Both the apoptotic suicide pathway and phagocytosis are required for a programmed cell death in Caenorhabditis elegans
BMC Biology (2016)
-
Programmed cell death and clearance of cell corpses in Caenorhabditis elegans
Cellular and Molecular Life Sciences (2016)
-
PDR-1/hParkin negatively regulates the phagocytosis of apoptotic cell corpses in Caenorhabditis elegans
Cell Death & Disease (2014)