Molecular & Cellular Toxicology

, Volume 15, Issue 1, pp 85–92 | Cite as

Regulatory role of Wdr24 in autophagy activity during zebrafish embryogenesis

  • Yong-Il Kim
  • In-Koo Nam
  • Jae-Young Um
  • Seong-Kyu ChoeEmail author
Original Paper



TOR and autophagy are essential pathways to mediate anabolic and catabolic reactions, respectively, in response to various nutritional stimuli. Vertebrate development requires such reactions to achieve the common goal of generating an independent organism from a single fertilized egg.


Using the zebrafish as an animal model, we characterized the role of Wdr24, a component of the GATOR2 complex that reportedly activates TORC1.


Sequence analysis and subcellular localization of zebrafish Wdr24 suggested functional resemblance to its mammalian counterpart. We found that wdr24 expression commences during early embryogenesis, implicating its requirement. Accordingly, wdr24 knockdown induced defective embryogenesis accompanied by massive cell death. The developmental defects induced by wdr24 knockdown were attributable, at least in part, to dysregulated autophagy, which could be partially restored by wdr24 overexpression.


These findings suggest that a conserved role of Wdr24 may be a critical part of the cellular metabolism in different species.


Wdr24 GATOR2 TORC1 Autophagy Zebrafish 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    He, C., Bartholomew, C. R., Zhou, W. & Klionsky, D. J. Assaying autophagic activity in transgenic GFP-Lc3 and GFP-Gabarap zebrafish embryos. Autophagy 5, 520–526 (2009).CrossRefGoogle Scholar
  2. 2.
    Boglev, Y. et al. Autophagy induction is a Tor-and Tp53-independent cell survival response in a zebrafish model of disrupted ribosome biogenesis. PLoS Genet 9, e1003279, doi:10.1371/journal.pgen.1003279 (2013).CrossRefGoogle Scholar
  3. 3.
    Skobo, T. et al. Zebrafish ambra1a and ambra1b knockdown impairs skeletal muscle development. PLoS One 9, e99210, doi:10.1371/journal.pone.0099210 (2014).CrossRefGoogle Scholar
  4. 4.
    Saxton, R. A. & Sabatini, D. M. mTOR Signaling in Growth, Metabolism, and Disease. Cell 168, 960–976, doi:10.1016/j.cell.2017.02.004 (2017).CrossRefGoogle Scholar
  5. 5.
    Laplante, M. et al. DEPTOR cell-autonomously promotes adipogenesis, and its expression is associated with obesity. Cell Metab 16, 202–212, doi:10.1016/j.cmet. 2012.07.008 (2012).CrossRefGoogle Scholar
  6. 6.
    Bar-Peled, L. et al. A Tumor suppressor complex with GAP activity for the Rag GTPases that signal amino acid sufficiency to mTORC1. Science 340, 1100–1106, doi:10.1126/science.1232044 (2013).CrossRefGoogle Scholar
  7. 7.
    Panchaud, N., Peli-Gulli, M. P. & De Virgilio, C. SEACing the GAP that nEGOCiates TORC1 activation: evolutionary conservation of Rag GTPase regulation. Cell Cycle 12, 2948–2952, doi:10.4161/cc.26000 (2013).CrossRefGoogle Scholar
  8. 8.
    Chantranupong, L. et al. The Sestrins interact with GATOR2 to negatively regulate the amino-acid-sensing pathway upstream of mTORC1. Cell Rep 9, 1–8, doi: 10.1016/j.celrep.2014.09.014 (2014).CrossRefGoogle Scholar
  9. 9.
    Wei, Y. et al. TORC1 regulators Iml1/GATOR1 and GATOR2 control meiotic entry and oocyte development in Drosophila. Proc Natl Acad Sci U S A 111, E5670–5677, doi:10.1073/pnas.1419156112 (2014).CrossRefGoogle Scholar
  10. 10.
    Platani, M., Trinkle-Mulcahy, L., Porter, M., Jeyaprakash, A. A. & Earnshaw, W. C. Mio depletion links mTOR regulation to Aurora A and Plk1 activation at mitotic centrosomes. J Cell Biol 210, 45–62, doi:10.1083/jcb. 201410001 (2015).CrossRefGoogle Scholar
  11. 11.
    Wei, Y., Reveal, B., Cai, W. & Lilly, M. A. The GATOR1 Complex Regulates Metabolic Homeostasis and the Response to Nutrient Stress in Drosophila melanogaster. G3 (Bethesda) 6, 3859–3867, doi:10.1534/g3.116.035337 (2016).CrossRefGoogle Scholar
  12. 12.
    Cai, W., Wei, Y., Jarnik, M., Reich, J. & Lilly, M. A. The GATOR2 Component Wdr24 Regulates TORC1 Activity and Lysosome Function. PLoS Genet 12, e1006036, doi:10.1371/journal.pgen.1006036 (2016).CrossRefGoogle Scholar
  13. 13.
    Iida, T. & Lilly, M. A. missing oocyte encodes a highly conserved nuclear protein required for the maintenance of the meiotic cycle and oocyte identity in Drosophila. Development 131, 1029–1039, doi:10.1242/dev.01001 (2004).CrossRefGoogle Scholar
  14. 14.
    Senger, S. et al. The nucleoporin Seh1 forms a complex with Mio and serves an essential tissue-specific function in Drosophila oogenesis. Development 138, 2133–2142, doi:10.1242/dev.057372 (2011).CrossRefGoogle Scholar
  15. 15.
    Robu, M. E. et al. p53 activation by knockdown technologies. PLoS Genet 3, e78, doi:10.1371/journal.pgen.0030078 (2007).CrossRefGoogle Scholar
  16. 16.
    Mizushima, N. & Komatsu, M. Autophagy: renovation of cells and tissues. Cell 147, 728–741, doi:10.1016/j.cell. 2011.10.026 (2011).CrossRefGoogle Scholar
  17. 17.
    Yang, P. & Zhang, H. You are what you eat: multifaceted functions of autophagy during C. elegans development. Cell Res 24, 80–91, doi:10.1038/cr.2013.154 (2014).CrossRefGoogle Scholar
  18. 18.
    McPhee, C. K. & Baehrecke, E. H. Autophagy in Drosophila melanogaster. Biochim Biophys Acta 1793, 1452–1460, doi:10.1016/j.bbamcr.2009.02.009 (2009).CrossRefGoogle Scholar
  19. 19.
    Behrends, C., Sowa, M. E., Gygi, S. P. & Harper, J. W. Network organization of the human autophagy system. Nature 466, 68–76, doi:10.1038/nature09204 (2010).CrossRefGoogle Scholar
  20. 20.
    Kimmel, C. B., Ballard, W. W., Kimmel, S. R., Ullmann, B. & Schilling, T. F. Stages of embryonic development of the zebrafish. Dev Dyn 203, 253–310, doi:10.1002/aja.1002030302 (1995).CrossRefGoogle Scholar
  21. 21.
    Kim, Y. I. et al. Developmental roles of D-bifunctional protein-A zebrafish model of peroxisome dysfunction. Mol Cells 37, 74–80, doi:10.14348/molcells.2014.2300 (2014).CrossRefGoogle Scholar
  22. 22.
    Kim, D. et al. Fis1 depletion in osteoarthritis impairs chondrocyte survival and peroxisomal and lysosomal function. J Mol Med (Berl) 94, 1373–1384, doi:10.1007/s00109-016-1445-9 (2016).CrossRefGoogle Scholar
  23. 23.
    Kim, M. J., Kang, K. H., Kim, C. H. & Choi, S. Y. Real-time imaging of mitochondria in transgenic zebrafish expressing mitochondrially targeted GFP. Biotechniques 45, 331–334, doi:10.2144/000112909 (2008).CrossRefGoogle Scholar
  24. 24.
    Bhandari, S. et al. The fatty acid chain elongase, Elovl1, is required for kidney and swim bladder development during zebrafish embryogenesis. Organogenesis 12, 78–93, doi:10.1080/15476278.2016.1172164 (2016).CrossRefGoogle Scholar
  25. 25.
    Kim, Y. I. et al. Cartilage development requires the function of Estrogen-related receptor alpha that directly regulates sox9 expression in zebrafish. Sci Rep 5, 18011, doi:10.1038/srep18011 (2015).CrossRefGoogle Scholar

Copyright information

© The Korean Society of Toxicogenomics and Toxicoproteomics and Springer Nature B.V. 2019

Authors and Affiliations

  • Yong-Il Kim
    • 1
  • In-Koo Nam
    • 2
  • Jae-Young Um
    • 3
  • Seong-Kyu Choe
    • 1
    Email author
  1. 1.Department of MicrobiologyWonkwang University School of MedicineIksanRepublic of Korea
  2. 2.Department of Biomedical Science & Engineering, Institute of Integrated TechnologyGwangju Institute of Science & TechnologyGwangjuRepublic of Korea
  3. 3.College of Korean Medicine, Basic Research Laboratory for Comorbidity Regulation, Graduate SchoolKyung Hee UniversitySeoulRepublic of Korea

Personalised recommendations