Planarian EGF repeat-containing genes megf6 and hemicentin are required to restrict the stem cell compartment

Autoři: Nicole Lindsay-Mosher aff001;  Andy Chan aff001;  Bret J. Pearson aff001
Působiště autorů: The Hospital for Sick Children, Program in Developmental and Stem Cell Biology, Toronto, Ontario, Canada aff001;  University of Toronto, Department of Molecular Genetics, Toronto, Ontario, Canada aff002;  Ontario Institute for Cancer Research, Toronto, Ontario, Canada aff003;  School of Biomedical Sciences, LKS Faculty of Medicine, Pokfulam, Hong Kong SAR, China aff003;  Ontario Institute for Cancer Research, Toronto, Ontario, Canada aff004
Vyšlo v časopise: Planarian EGF repeat-containing genes megf6 and hemicentin are required to restrict the stem cell compartment. PLoS Genet 16(2): e32767. doi:10.1371/journal.pgen.1008613
Kategorie: Research Article
doi: 10.1371/journal.pgen.1008613


The extracellular matrix (ECM) is important for maintaining the boundaries between tissues. This role is particularly critical in the stem cell niche, as pre-neoplastic or cancerous stem cells must pass these boundaries in order to invade into the surrounding tissue. Here, we examine the role of the ECM as a regulator of the stem cell compartment in the planarian Schmidtea mediterranea, a highly regenerative, long-lived organism with a large population of adult stem cells. We identify two EGF repeat-containing genes, megf6 and hemicentin, with identical knockdown phenotypes. We find that megf6 and hemicentin are needed to maintain the structure of the basal lamina, and in the absence of either gene, pluripotent stem cells migrate ectopically outside of their compartment and hyper-proliferate, causing lesions in the body wall muscle. These muscle lesions and ectopic stem cells are also associated with ectopic gut branches, which protrude from the normal gut towards the dorsal side of the animal. Interestingly, both megf6 and hemicentin knockdown worms are capable of regenerating tissue free of both muscle lesions and ectopic cells, indicating that these genes are dispensable for regeneration. These results provide insight into the role of planarian ECM in restricting the stem cell compartment, and suggest that signals within the compartment may act to suppress stem cell hyperproliferation.

Klíčová slova:

Epidermis – Muscle fibers – Pigments – Planarians – RNA interference – Stem cells – Stem cell niche – Basement membrane


1. Pellettieri J, Alvarado AS. Cell Turnover and Adult Tissue Homeostasis: From Humans to Planarians. Annu Rev Genet. 2007;41: 83–105. doi: 10.1146/annurev.genet.41.110306.130244 18076325

2. Sahu S, Dattani A, Aboobaker AA. Secrets from immortal worms: What can we learn about biological ageing from the planarian model system? Semin Cell Dev Biol. 2017;70: 108–121. doi: 10.1016/j.semcdb.2017.08.028 28818620

3. Ahmed M, Ffrench-Constant C. Extracellular Matrix Regulation of Stem Cell Behavior. Curr stem cell reports. 2016;2: 197–206. doi: 10.1007/s40778-016-0056-2 27547708

4. Voog J, Jones DL. Stem Cells and the Niche: A Dynamic Duo. Cell Stem Cell. 2010;6: 103–115. doi: 10.1016/j.stem.2010.01.011 20144784

5. Rossi L, Salvetti A. Planarian stem cell niche, the challenge for understanding tissue regeneration. Semin Cell Dev Biol. 2019;87: 30–36. doi: 10.1016/j.semcdb.2018.03.005 29534938

6. Rozario T, DeSimone DW. The extracellular matrix in development and morphogenesis: a dynamic view. Dev Biol. 2010;341: 126–40. doi: 10.1016/j.ydbio.2009.10.026 19854168

7. Daley WP, Peters SB, Larsen M. Extracellular matrix dynamics in development and regenerative medicine. J Cell Sci. 2008;121: 255–64. doi: 10.1242/jcs.006064 18216330

8. Witjas FMR, van den Berg BM, van den Berg CW, Engelse MA, Rabelink TJ. Concise Review: The Endothelial Cell Extracellular Matrix Regulates Tissue Homeostasis and Repair. Stem Cells Transl Med. 2019;8: 375–382. doi: 10.1002/sctm.18-0155 30537441

9. Castro-Castro A, Marchesin V, Monteiro P, Lodillinsky C, Rossé C, Chavrier P. Cellular and Molecular Mechanisms of MT1-MMP-Dependent Cancer Cell Invasion. Annu Rev Cell Dev Biol. 2016;32: 555–576. doi: 10.1146/annurev-cellbio-111315-125227 27501444

10. Verma D, Zanetti C, Fontenay M, Krause DS. Bone Marrow Niche-Derived Extracellular Matrix-Degrading Enzymes Influence the Progression of B-Cell Acute Lymphoblastic Leukemia. Blood. 2018;132: 390–390. doi: 10.1182/BLOOD-2018-99-110492

11. Vorotnikova E, McIntosh D, Dewilde A, Zhang J, Reing JE, Zhang L, et al. Extracellular matrix-derived products modulate endothelial and progenitor cell migration and proliferation in vitro and stimulate regenerative healing in vivo. Matrix Biol. 2010;29: 690–700. doi: 10.1016/j.matbio.2010.08.007 20797438

12. Wehner D, Tsarouchas TM, Michael A, Haase C, Weidinger G, Reimer MM, et al. Wnt signaling controls pro-regenerative Collagen XII in functional spinal cord regeneration in zebrafish. Nat Commun. 2017;8: 126. doi: 10.1038/s41467-017-00143-0 28743881

13. Zhu SJ, Pearson BJ. (Neo)blast from the past: new insights into planarian stem cell lineages. Curr Opin Genet Dev. 2016;40: 74–80. doi: 10.1016/j.gde.2016.06.007 27379899

14. Wagner DE, Wang IE, Reddien PW. Clonogenic Neoblasts Are Pluripotent Adult Stem Cells That Underlie Planarian Regeneration. Science (80-). 2011;332: 811–816. doi: 10.1126/science.1203983 21566185

15. Zeng A, Li H, Guo L, Gao X, McKinney S, Wang Y, et al. Prospectively Isolated Tetraspanin+ Neoblasts Are Adult Pluripotent Stem Cells Underlying Planaria Regeneration. Cell. 2018;173: 1593–1608.e20. doi: 10.1016/j.cell.2018.05.006 29906446

16. Reddien PW, Sánchez Alvarado A. Fundamentals of planarian regeneration. Annu Rev Cell Dev Biol. 2004;20: 725–57. doi: 10.1146/annurev.cellbio.20.010403.095114 15473858

17. Salo E, Abril JF, Adell T, Cebria F, Eckelt K, Fernandez-Taboada E, et al. Planarian regeneration: achievements and future directions after 20 years of research. Int J Dev Biol. 2009;53: 1317–1327. doi: 10.1387/ijdb.072414es 19247944

18. Lai AG, Aboobaker AA. EvoRegen in animals: Time to uncover deep conservation or convergence of adult stem cell evolution and regenerative processes. Dev Biol. 2018;433: 118–131. doi: 10.1016/j.ydbio.2017.10.010 29198565

19. Pearson BJ, Sánchez Alvarado A. A planarian p53 homolog regulates proliferation and self-renewal in adult stem cell lineages. Development. 2010;137: 213–21. doi: 10.1242/dev.044297 20040488

20. Newmark PA, Sánchez Alvarado A. Bromodeoxyuridine Specifically Labels the Regenerative Stem Cells of Planarians. Dev Biol. 2000;220: 142–153. doi: 10.1006/dbio.2000.9645 10753506

21. Bonar NA, Petersen CP. Integrin suppresses neurogenesis and regulates brain tissue assembly in planarian regeneration. Development. 2017;144: 784–794. doi: 10.1242/dev.139964 28126842

22. Abnave P, Aboukhatwa E, Kosaka N, Thompson J, Hill MA, Aboobaker AA. Epithelial-mesenchymal transition transcription factors control pluripotent adult stem cell migration in vivo in planarians. Development. 2017;144: 3440–3453. doi: 10.1242/dev.154971 28893948

23. Brizzi MF, Tarone G, Defilippi P. Extracellular matrix, integrins, and growth factors as tailors of the stem cell niche. Curr Opin Cell Biol. 2012;24: 645–651. doi: 10.1016/ 22898530

24. Fraguas S, Barberán S, Cebrià F. EGFR signaling regulates cell proliferation, differentiation and morphogenesis during planarian regeneration and homeostasis. Dev Biol. 2011;354: 87–101. doi: 10.1016/j.ydbio.2011.03.023 21458439

25. Lei K, Thi-Kim Vu H, Mohan RD, McKinney SA, Seidel CW, Alexander R, et al. Egf Signaling Directs Neoblast Repopulation by Regulating Asymmetric Cell Division in Planarians. Dev Cell. 2016;38: 413–429. doi: 10.1016/j.devcel.2016.07.012 27523733

26. Cote LE, Simental E, Reddien PW. Muscle functions as a connective tissue and source of extracellular matrix in planarians. Nat Commun. 2019;10: 1592. doi: 10.1038/s41467-019-09539-6 30962434

27. Awasaki T, Tatsumi R, Takahashi K, Arai K, Nakanishi Y, Ueda R, et al. Essential Role of the Apoptotic Cell Engulfment Genes draper and ced-6 in Programmed Axon Pruning during Drosophila Metamorphosis. Neuron. 2006;50: 855–867. doi: 10.1016/j.neuron.2006.04.027 16772168

28. Draper I, Mahoney LJ, Mitsuhashi S, Pacak CA, Salomon RN, Kang PB. Silencing of drpr leads to muscle and brain degeneration in adult Drosophila. Am J Pathol. 2014;184: 2653–61. doi: 10.1016/j.ajpath.2014.06.018 25111228

29. Manaka J, Kuraishi T, Shiratsuchi A, Nakai Y, Higashida H, Henson P, et al. Draper-mediated and Phosphatidylserine-independent Phagocytosis of Apoptotic Cells by Drosophila Hemocytes/Macrophages. J Biol Chem. 2004;279: 48466–48476. doi: 10.1074/jbc.M408597200 15342648

30. Fincher CT, Wurtzel O, de Hoog T, Kravarik KM, Reddien PW. Cell type transcriptome atlas for the planarian Schmidtea mediterranea. Science. 2018; eaaq1736. doi: 10.1126/science.aaq1736 29674431

31. Ross KG, Omuro KC, Taylor MR, Munday RK, Hubert A, King RS, et al. Novel monoclonal antibodies to study tissue regeneration in planarians. BMC Dev Biol. 2015;15: 2. doi: 10.1186/s12861-014-0050-9 25604901

32. Stubenhaus BM, Dustin JP, Neverett ER, Beaudry MS, Nadeau LE, Burk-McCoy E, et al. Light-induced depigmentation in planarians models the pathophysiology of acute porphyrias. Elife. 2016;5. doi: 10.7554/eLife.14175 27240733

33. He X, Lindsay-Mosher N, Li Y, Molinaro A, Pellettieri J, Pearson B. FOX and ETS family transcription factors regulate the pigment cell lineage in planarians. Development. 2017;144: 4540–4551. doi: 10.1242/dev.156349 29158443

34. Zhou Z, Hartwieg E, Horvitz HR. CED-1 is a transmembrane receptor that mediates cell corpse engulfment in C. elegans. Cell. 2001;104: 43–56. Available: doi: 10.1016/s0092-8674(01)00190-8 11163239

35. Scheib JL, Sullivan CS, Carter BD. Jedi-1 and MEGF10 Signal Engulfment of Apoptotic Neurons through the Tyrosine Kinase Syk. J Neurosci. 2012;32: 13022–13031. doi: 10.1523/JNEUROSCI.6350-11.2012 22993420

36. Hamon Y, Trompier D, Ma Z, Venegas V, Pophillat M, Mignotte V, et al. Cooperation between engulfment receptors: the case of ABCA1 and MEGF10. PLoS One. 2006;1: e120. doi: 10.1371/journal.pone.0000120 17205124

37. Ziegenfuss JS, Biswas R, Avery MA, Hong K, Sheehan AE, Yeung Y-G, et al. Draper-dependent glial phagocytic activity is mediated by Src and Syk family kinase signalling. Nature. 2008;453: 935–9. doi: 10.1038/nature06901 18432193

38. Gumienny TL, Brugnera E, Tosello-Trampont A-C, Kinchen JM, Haney LB, Nishiwaki K, et al. CED-12/ELMO, a Novel Member of the CrkII/Dock180/Rac Pathway, Is Required for Phagocytosis and Cell Migration. Cell. 2001;107: 27–41. doi: 10.1016/s0092-8674(01)00520-7 11595183

39. Sullivan CS, Scheib JL, Ma Z, Dang RP, Schafer JM, Hickman FE, et al. The adaptor protein GULP promotes Jedi-1-mediated phagocytosis through a clathrin-dependent mechanism. Mol Biol Cell. 2014;25: 1925–1936. doi: 10.1091/mbc.E13-11-0658 24743597

40. Hill EM, Petersen CP. Positional information specifies the site of organ regeneration and not tissue maintenance in planarians. Elife. 2018;7. doi: 10.7554/eLife.33680 29547123

41. Atabay KD, LoCascio SA, de Hoog T, Reddien PW. Self-organization and progenitor targeting generate stable patterns in planarian regeneration. Science (80-). 2018;360: 404–409. doi: 10.1126/science.aap8179 29545509

42. Nishimura K, Kitamura Y, Taniguchi T, Agata K. Analysis of motor function modulated by cholinergic neurons in planarian dugesia japonica. Neuroscience. 2010;168: 18–30. doi: 10.1016/j.neuroscience.2010.03.038 20338223

43. van Wolfswinkel JC, Wagner DE, Reddien PW. Single-cell analysis reveals functionally distinct classes within the planarian stem cell compartment. Cell Stem Cell. 2014;15: 326–39. doi: 10.1016/j.stem.2014.06.007 25017721

44. Vogel BE, Muriel JM, Dong C, Xu X. Hemicentins: What have we learned from worms? Cell Res. 2006;16: 872–878. doi: 10.1038/ 17031392

45. Feitosa NM, Zhang J, Carney TJ, Metzger M, Korzh V, Bloch W, et al. Hemicentin 2 and Fibulin 1 are required for epidermal–dermal junction formation and fin mesenchymal cell migration during zebrafish development. Dev Biol. 2012;369: 235–248. doi: 10.1016/j.ydbio.2012.06.023 22771579

46. Muriel JM, Dong C, Hutter H, Vogel BE. Fibulin-1C and Fibulin-1D splice variants have distinct functions and assemble in a hemicentin-dependent manner. Development. 2005;132: 4223–34. doi: 10.1242/dev.02007 16120639

47. Dong C, Muriel JM, Ramirez S, Hutter H, Hedgecock EM, Breydo L, et al. Hemicentin Assembly in the Extracellular Matrix Is Mediated by Distinct Structural Modules. J Biol Chem. 2006;281: 23606–23610. doi: 10.1074/jbc.M513589200 16798744

48. Camaj P, Seeliger H, Ischenko I, Krebs S, Blum H, De Toni EN, et al. EFEMP1 binds the EGF receptor and activates MAPK and Akt pathways in pancreatic carcinoma cells. Biol Chem. 2009;390: 1293–302. doi: 10.1515/BC.2009.140 19804359

49. Hu H, Wang M, Wang H, Liu Z, Guan X, Yang R, et al. MEGF6 Promotes the Epithelial-to-Mesenchymal Transition via the TGFβ/SMAD Signaling Pathway in Colorectal Cancer Metastasis. Cell Physiol Biochem. 2018;46: 1895–1906. doi: 10.1159/000489374 29719292

50. Hanahan D, Weinberg RA. Hallmarks of cancer: the next generation. Cell. 2011;144: 646–74. doi: 10.1016/j.cell.2011.02.013 21376230

51. Alvarado AS, Newmark PA, Robb SM, Juste R. The Schmidtea mediterranea database as a molecular resource for studying platyhelminthes, stem cells and regeneration. Development. 2002;129: 5659–5665. doi: 10.1242/dev.00167 12421706

52. Newmark PA, Reddien PW, Cebria F, Alvarado AS. Ingestion of bacterially expressed double-stranded RNA inhibits gene expression in planarians. Proc Natl Acad Sci. 2003;100: 11861–11865. doi: 10.1073/pnas.1834205100 12917490

53. Cowles MW, Brown DDR, Nisperos S V., Stanley BN, Pearson BJ, Zayas RM. Genome-wide analysis of the bHLH gene family in planarians identifies factors required for adult neurogenesis and neuronal regeneration. Development. 2013;140: 4691–4702. doi: 10.1242/dev.098616 24173799

54. Rozanski A, Moon H, Brandl H, Martín-Durán JM, Grohme MA, Hüttner K, et al. PlanMine 3.0—improvements to a mineable resource of flatworm biology and biodiversity. Nucleic Acids Res. 2019;47: D812–D820. doi: 10.1093/nar/gky1070 30496475

55. Lauter G, Söll I, Hauptmann G. Two-color fluorescent in situ hybridization in the embryonic zebrafish brain using differential detection systems. BMC Dev Biol. 2011;11: 43. doi: 10.1186/1471-213X-11-43 21726453

56. Pearson BJ, Eisenhoffer GT, Gurley KA, Rink JC, Miller DE, Sánchez Alvarado A. Formaldehyde-based whole-mount in situ hybridization method for planarians. Dev Dyn. 2009;238: 443–50. doi: 10.1002/dvdy.21849 19161223

57. Currie KW, Brown DDR, Zhu S, Xu C, Voisin V, Bader GD, et al. HOX gene complement and expression in the planarian Schmidtea mediterranea. Evodevo. 2016;7: 7. doi: 10.1186/s13227-016-0044-8 27034770

58. Raz AA, Srivastava M, Salvamoser R, Reddien PW. Acoel regeneration mechanisms indicate an ancient role for muscle in regenerative patterning. Nat Commun. 2017;8: 1260. doi: 10.1038/s41467-017-01148-5 29084955

59. Pellettieri J, Fitzgerald P, Watanabe S, Mancuso J, Green DR, Sánchez Alvarado A. Cell death and tissue remodeling in planarian regeneration. Dev Biol. 2010;338: 76–85. doi: 10.1016/j.ydbio.2009.09.015 19766622

60. Zhu SJ, Hallows SE, Currie KW, Xu C, Pearson BJ. A mex3 homolog is required for differentiation during planarian stem cell lineage development. Elife. 2015;4. doi: 10.7554/eLife.07025 26114597

61. Castillo-Lara S, Pascual-Carreras E, Abril JF. PlanExp: intuitive integration of complex RNA-seq datasets with planarian omics resources. Bioinformatics. 2019; doi: 10.1093/bioinformatics/btz802 31647529

62. Eisenhoffer GT, Kang H, Alvarado AS. Molecular Analysis of Stem Cells and Their Descendants during Cell Turnover and Regeneration in the Planarian Schmidtea mediterranea. Cell Stem Cell. 2008;3: 327–339. doi: 10.1016/j.stem.2008.07.002 18786419

Článek vyšel v časopise

PLOS Genetics

2020 Číslo 2

Nejčtenější v tomto čísle

Tomuto tématu se dále věnují…


Zvyšte si kvalifikaci online z pohodlí domova

Antiseptika a prevence ve stomatologii
nový kurz
Autoři: MUDr. Ladislav Korábek, CSc., MBA

Citikolin v neuroprotekci a neuroregeneraci: od výzkumu do klinické praxe nejen očních lékařů
Autoři: MUDr. Petr Výborný, CSc., FEBO

Zánětlivá bolest zad a axiální spondylartritida – Diagnostika a referenční strategie
Autoři: MUDr. Monika Gregová, Ph.D., MUDr. Kristýna Bubová

Diagnostika a léčba deprese pro ambulantní praxi
Autoři: MUDr. Jan Hubeňák, Ph.D

Význam nemocničního alert systému v době SARS-CoV-2
Autoři: doc. MUDr. Helena Lahoda Brodská, Ph.D., prim. MUDr. Václava Adámková

Všechny kurzy
Kurzy Doporučená témata Časopisy
Zapomenuté heslo

Nemáte účet?  Registrujte se

Zapomenuté heslo

Zadejte e-mailovou adresu, se kterou jste vytvářel(a) účet, budou Vám na ni zaslány informace k nastavení nového hesla.


Nemáte účet?  Registrujte se