Wurst is essential for airway clearance and respiratory-tube size control

Abstract

The Drosophila melanogaster tracheal system and the mammalian lung are branching networks of tubular epithelia that convert during late embryogenesis from liquid- to air-filling1,2,3. Little is known about how respiratory-tube size and physiology are coordinated. Here, we show that the Drosophila wurst gene encodes a unique J-domain transmembrane protein highly conserved in metazoa. In wurst mutants, respiratory-tube length is increased and lumen clearance is abolished, preventing gas filling of the airways. Wurst is essential for clathrin-mediated endocytosis4, which is required for size determination and lumen clearance of the airways. wurst recruits heat shock cognate protein 70-4 and clathrin to the apical membrane of epithelial cells. The sequence conservation of the single Wurst orthologues in mice and humans offer new opportunities for genetic studies of clinically relevant lung syndromes caused by the failure of liquid clearance and respiratory-tube size control.

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Figure 1: Wurst is a conserved protein required for respiratory-tube size control.
Figure 2: Wurst is required for apical ECM organization and respiratory lumen clearance.
Figure 3: Wurst interacts with hsc70-4 and clathrin.
Figure 4: Wurst-dependent endocytosis is essential for tube-size regulation and lumen clearance.

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References

  1. 1

    Manning, G. & Krasnow, M. in The Development of Drosophila melanogaster. (eds Bate,M. & Martinez Arias, A.) 609–685 (Cold Spring Harbor Laboratory Press, Cold Spring Harbor, 1993).

  2. 2

    Olver, R. E., Walters, D. V. & M. Wilson, S. Developmental regulation of lung liquid transport. Annu. Rev. Physiol. 66, 77–101 (2004).

  3. 3

    Affolter, M. et al. Tube or not tube: remodeling epithelial tissues by branching morphogenesis. Dev. Cell 4, 11–18 (2003).

  4. 4

    Conner, S. D. & Schmid, S. L. Regulated portals of entry into the cell. Nature 422, 37–44 (2003).

  5. 5

    Hogan, B. L. M. & Kolodziej, P. A. Organogenesis: molecular mechanisms of tubulogenesis. Nature Rev. Genet. 3, 513–523 (2002).

  6. 6

    Davis, G. E. & Senger, D. R. Endothelial extracellular matrix: biosynthesis, remodeling, and functions during vascular morphogenesis and neovessel stabilization. Circ. Res. 97, 1093–1107 (2005).

  7. 7

    Fischer, H. & Widdicombe, J. H. Mechanisms of acid and base secretion by the airway epithelium. J. Membr. Biol. 211, 139–150 (2006).

  8. 8

    Metzger, R. J. & Krasnow, M. A. Genetic control of branching morphogenesis. Science 284, 1635–1639 (1999).

  9. 9

    Beitel, G. J. & Krasnow, M. A. Genetic control of epithelial tube size in the Drosophila tracheal system. Development 127, 3271–3282 (2000).

  10. 10

    O'Brodovich, H. M. Immature epithelial Na+ channel expression is one of the pathogenetic mechanisms leading to human neonatal respiratory distress syndrome. Proc. Assoc. Am. Physicians 108, 345–355 (1996).

  11. 11

    Ungewickell, E. et al. Role of auxilin in uncoating clathrin-coated vesicles. Nature 378, 632–635 (1995).

  12. 12

    Bukau, B., Weissman, J. & Horwich, A. Molecular chaperones and protein quality control. Cell 125, 443–451 (2006).

  13. 13

    Kelley, W. L. Molecular chaperones: How J domains turn on Hsp70s. Curr. Biol. 9, R305–R308 (1999).

  14. 14

    Pellecchia, M. et al. NMR structure of the J-domain and the Gly/Phe-rich region of the Escherichia coli DnaJ chaperone. J. Mol. Biol. 260, 236–250 (1996).

  15. 15

    Behr, M., Riedel, D. & Schuh, R. The claudin-like megatrachea is essential in septate junctions for the epithelial barrier function in Drosophila. Dev. Cell 5, 611–620 (2003).

  16. 16

    Wu, V. M. et al. Sinuous is a Drosophila claudin required for septate junction organization and epithelial tube size control. J. Cell Biol. 164, 313–323 (2004).

  17. 17

    Tonning, A. et al. A transient luminal chitinous matrix is required to model epithelial tube diameter in the Drosophila trachea. Dev. Cell 9, 423–430 (2005).

  18. 18

    Devine, W. P. et al. Requirement for chitin biosynthesis in epithelial tube morphogenesis. Proc. Natl Acad. Sci. USA 102, 17014–17019 (2005).

  19. 19

    Luschnig, S. et al. serpentine and vermiform encode matrix proteins with chitin binding and deacetylation domains that limit tracheal tube length in Drosophila. Curr. Biol. 16, 186–194 (2006).

  20. 20

    Wang, S. et al. Septate-junction-dependent luminal deposition of chitin deacetylases restricts tube elongation in the Drosophila trachea. Curr. Biol. 16, 180–185 (2006).

  21. 21

    Moussian, B. et al. Drosophila Knickkopf and Retroactive are needed for epithelial tube growth and cuticle differentiation through their specific requirement for chitin filament organization. Development 133, 163–171 (2006).

  22. 22

    Wucherpfennig, T., Wilsch-Brauninger, M. & Gonzalez-Gaitan, M. Role of Drosophila Rab5 during endosomal trafficking at the synapse and evoked neurotransmitter release. J. Cell Biol. 161, 609–624 (2003).

  23. 23

    Bronk, P. et al. Drosophila Hsc70-4 is critical for neurotransmitter exocytosis in vivo. Neuron 30, 475–488 (2001).

  24. 24

    Marks, B. et al. GTPase activity of dynamin and resulting conformation change are essential for endocytosis. Nature 410, 231–235 (2001).

  25. 25

    Chang, H. C. et al. Hsc70 is required for endocytosis and clathrin function in Drosophila. J. Cell Biol. 159, 477–487 (2002).

  26. 26

    Chang, H. C., Hull, M. & Mellman, I. The J-domain protein Rme-8 interacts with Hsc70 to control clathrin-dependent endocytosis in Drosophila. J. Cell Biol. 164, 1055–1064 (2004).

  27. 27

    Newmyer, S. L., Christensen, A. & Sever, S. Auxilin–dynamin interactions link the uncoating ATPase chaperone machinery with vesicle formation. Dev. Cell 4, 929–940 (2003).

  28. 28

    Liu, L., Johnson, W. A. & Welsh, M. J. Drosophila DEG/ENaC pickpocket genes are expressed in the tracheal system, where they may be involved in liquid clearance. Proc. Natl Acad. Sci. USA 100, 2128–2133 (2003).

  29. 29

    Hummler, E. et al. Early death due to defective neonatal lung liquid clearance in a-ENaC-deficient mice. Nature Genetics 12, 325–328 (1996).

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Acknowledgements

We thank: C. Samakovlis for communicating unpublished results; M. Affolter, R. Fehon, M. González-Gaitán, L. Liu, B. Moussian, K. Palter, D. F. Ready, U. Schäfer and S. Luschnig for sharing fly stocks and reagents; T. Magin, I. Zinke and B. Fuss for comments on the manuscript; and the members of the Hoch laboratory for helpful discussions. M.B. would like to thank L. Kutschenko, V. Arndt, J. Martini and all members of the Hoch laboratory for technical assistance. This work was supported by grants from the Deutsche Forschungsgemeinschaft (DFG) to M.B. (BE3215) and to M.H. (SFB 645).

Author information

Norther blot, electron microscopic studies and clathrin interaction assay were performed by C. Wingen; molecular analysis of the l(1)G0162 P-element was performed by C. Wolf; all other experiments were performed by M.B.; the wurst project was initiated by M.B. and R.S.; M.H. supervised the research project; M.H. wrote the manuscript; all authors discussed the experimental results.

Correspondence to Michael Hoch.

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The authors declare no competing financial interests.

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Supplementary Figures S1, S2, S3, S4 and S5 (PDF 1950 kb)

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Behr, M., Wingen, C., Wolf, C. et al. Wurst is essential for airway clearance and respiratory-tube size control. Nat Cell Biol 9, 847–853 (2007). https://doi.org/10.1038/ncb1611

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