Abstract
In both yeast and mammals, uncapped telomeres activate the DNA damage response (DDR) and undergo end-to-end fusion1,2. Previous work has shown that the Drosophila HOAP protein, encoded by the caravaggio (cav) gene, is required to prevent telomeric fusions3. Here we show that HOAP-depleted telomeres activate both the DDR and the spindle assembly checkpoint (SAC). The cell cycle arrest elicited by the DDR was alleviated by mutations in mei-41 (encoding ATR), mus304 (ATRIP), grp (Chk1) and rad50 but not by mutations in tefu (ATM). The SAC was partially overridden by mutations in zw10 (also known as mit(1)15) and bubR1, and also by mutations in mei-41, mus304, rad50, grp and tefu. As expected from SAC activation, the SAC proteins Zw10, Zwilch, BubR1 and Cenp-meta (Cenp-E) accumulated at the kinetochores of cav mutant cells. Notably, BubR1 also accumulated at cav mutant telomeres in a mei-41-, mus304-, rad50-, grp- and tefu-dependent manner. Our results collectively suggest that recruitment of BubR1 by dysfunctional telomeres inhibits Cdc20-APC function, preventing the metaphase-to-anaphase transition.
This is a preview of subscription content, access via your institution
Relevant articles
Open Access articles citing this article.
-
A role for Separase in telomere protection
Nature Communications Open Access 18 January 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
Prices vary by article type
from$1.95
to$39.95
Prices may be subject to local taxes which are calculated during checkout



References
de Lange, T. Shelterin: the protein complex that shapes and safeguards human telomeres. Genes Dev. 19, 2100–2110 (2005).
Lydall, D. Hiding at the ends of yeast chromosomes: telomeres, nucleases and checkpoint pathways. J. Cell Sci. 116, 4057–4065 (2003).
Cenci, G., Siriaco, G., Raffa, G.D., Kellum, R. & Gatti, M. The Drosophila HOAP protein is required for telomere capping. Nat. Cell Biol. 5, 82–84 (2003).
Cenci, G., Ciapponi, L. & Gatti, M. The mechanism of telomere protection: a comparison between Drosophila and humans. Chromosoma 114, 135–145 (2005).
Cenci, G. et al. UbcD1, a Drosophila ubiquitin-conjugating enzyme required for proper telomere behavior. Genes Dev. 11, 863–875 (1997).
Fanti, L., Giovinazzo, G., Berloco, M. & Pimpinelli, S. The heterochromatin protein 1 prevents telomere fusions in Drosophila. Mol. Cell 2, 527–538 (1998).
Bi, X. et al. Drosophila ATM and ATR checkpoint kinases control partially redundant pathways for telomere maintenance. Proc. Natl. Acad. Sci. USA 102, 15167–15172 (2005).
Bi, X., Wei, S.C. & Rong, Y.S. Telomere protection without a telomerase; the role of ATM and Mre11 in Drosophila telomere maintenance. Curr. Biol. 14, 1348–1353 (2004).
Ciapponi, L. et al. The Drosophila Mre11/Rad50 complex is required to prevent both telomeric fusion and chromosome breakage. Curr. Biol. 14, 1360–1366 (2004).
Ciapponi, L., Cenci, G. & Gatti, M. The Drosophila Nbs protein functions in multiple pathways for the maintenance of genome stability. Genetics 173, 1447–1454 (2006).
Oikemus, S.R. et al. Drosophila atm/telomere fusion is required for telomeric localization of HP1 and telomere position effect. Genes Dev. 18, 1850–1861 (2004).
Oikemus, S.R. et al. Epigenetic telomere protection by Drosophila DNA damage response pathways. PLoS Genet. 2, e71 (2006).
Silva, E. et al. ATM is required for telomere maintenance and chromosome stability during Drosophila development. Curr. Biol. 14, 1341–1347 (2004).
Song, Y.H., Mirey, G., Betson, M., Haber, D.A. & Settleman, J. The Drosophila ATM ortholog, dATM, mediates the response to ionizing radiation and to spontaneous DNA damage during development. Curr. Biol. 14, 1354–1359 (2004).
Raffa, G.D., Cenci, G., Siriaco, G., Goldberg, M.L. & Gatti, M. The putative Drosophila transcription factor woc is required to prevent telomeric fusions. Mol. Cell 20, 821–831 (2005).
Karess, R. Rod-Zw10-Zwilch: a key player in the spindle checkpoint. Trends Cell Biol. 15, 386–392 (2005).
Musacchio, A. & Salmon, E.D. The spindle-assembly checkpoint in space and time. Nat. Rev. Mol. Cell Biol. 8, 379–393 (2007).
Hari, K.L. et al. The mei-41 gene of D. melanogaster is a structural and functional homolog of the human ataxia telangiectasia gene. Cell 82, 815–821 (1995).
Brodsky, M.H., Sekelsky, J.J., Tsang, G., Hawley, R.S. & Rubin, G.M. mus304 encodes a novel DNA damage checkpoint protein required during Drosophila development. Genes Dev. 14, 666–678 (2000).
Fogarty, P. et al. The Drosophila grapes gene is related to checkpoint gene chk1/rad27 and is required for late syncytial division fidelity. Curr. Biol. 7, 418–426 (1997).
Royou, A., Macias, H. & Sullivan, W. The Drosophila Grp/Chk1 DNA damage checkpoint controls entry into anaphase. Curr. Biol. 15, 334–339 (2005).
Sancar, A., Lindsey-Boltz, L.A., Unsal-Kacmaz, K. & Linn, S. Molecular mechanisms of mammalian DNA repair and the DNA damage checkpoints. Annu. Rev. Biochem. 73, 39–85 (2004).
Williams, B.C., Murphy, T.D., Goldberg, M.L. & Karpen, G.H. Neocentromere activity of structurally acentric mini-chromosomes in Drosophila. Nat. Genet. 18, 30–37 (1998).
Heeger, S. et al. Genetic interactions of separase regulatory subunits reveal the diverged Drosophila Cenp-C homolog. Genes Dev. 19, 2041–2053 (2005).
Basto, R., Gomes, R. & Karess, R.E. Rough deal and Zw10 are required for the metaphase checkpoint in Drosophila. Nat. Cell Biol. 2, 939–943 (2000).
Mikhailov, A., Cole, R.W. & Rieder, C.L. DNA damage during mitosis in human cells delays the metaphase/anaphase transition via the spindle-assembly checkpoint. Curr. Biol. 12, 1797–1806 (2002).
Miller, K.M. & Cooper, J.P. The telomere protein Taz1 is required to prevent and repair genomic DNA breaks. Mol. Cell 11, 303–313 (2003).
Maringele, L. & Lydall, D. EXO1-dependent single-stranded DNA at telomeres activates subsets of DNA damage and spindle checkpoint pathways in budding yeast yku70Delta mutants. Genes Dev. 16, 1919–1933 (2002).
Bentley, A.M., Williams, B.C., Goldberg, M.L. & Andres, A.J. Phenotypic characterization of Drosophila ida mutants: defining the role of APC5 in cell cycle progression. J. Cell Sci. 115, 949–961 (2002).
Acknowledgements
We thank M.L. Goldberg, B. Williams, C. Sunkel, C. Lehner, T. Megraw, J. Raff, T. Kaufman and T.T. Su for providing antibodies and Drosophila strains, and M.L. Goldberg for critical comments on the manuscript. This work was supported by grants from the Italian Association for Cancer Research (AIRC) and Telethon to M.G. and by a grant for Progetti di Ricerca di Interesse Nazionale (PRIN) from Ministero dell'Università e Ricerca (MIUR) to G.C.
Author information
Authors and Affiliations
Contributions
G.C. and M.G. conceived and designed the experiments. M.M. carried out cytological analyses. L.C. and G.C. constructed and partially characterized the double mutants. B.F. performed in vivo imaging. G.C. and M.G. analyzed the data and wrote the paper.
Corresponding author
Supplementary information
Supplementary Text and Figures
Supplementary Methods, Supplementary Figures 1–3 (PDF 3906 kb)
Supplementary Video 1
Visualization of the mitotic division of a wild type neuroblast expressing His2AvDGFP. (AVI 430 kb)
Supplementary Video 2
Visualization of the delayed mitotic division of a cav mutant neuroblast expressing His2AvDGFP. (AVI 879 kb)
Supplementary Video 3
Visualization of the delayed mitotic division of a cav/ Df(3R)crb-F89-4 mutant neuroblast expressing His2AvDGFP. (AVI 571 kb)
Rights and permissions
About this article
Cite this article
Musarò, M., Ciapponi, L., Fasulo, B. et al. Unprotected Drosophila melanogaster telomeres activate the spindle assembly checkpoint. Nat Genet 40, 362–366 (2008). https://doi.org/10.1038/ng.2007.64
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/ng.2007.64
This article is cited by
-
A role for Separase in telomere protection
Nature Communications (2016)
-
Safeguarding genetic information in Drosophila
Chromosoma (2011)