Volume 4 Supplement 1

Proceedings of the Second International Cilia in Development and Disease Scientific Conference (2014)

Open Access

The role of Rabconnectin3a in cilia length regulation

  • B Tavares1,
  • P Pintado1 and
  • SS Lopes1
Cilia20154(Suppl 1):P70

https://doi.org/10.1186/2046-2530-4-S1-P70

Published: 13 July 2015

Background

Using the zebrafish mutant for the deltaD gene (dld -/- ), it was shown the involvement of Notch signaling in the control of cilia length in the cells of the fish laterality organ (Kupffer's Vesicle, KV) [1]. Further research based on KV specific microarray screening allowed the discovery of several genes with differential expression. Of these, 23% were associated with ciliogenesis and upon analysis, many proved to be involved in cellular trafficking.

Rabconnectin3a or rbcn3a was strongly downregulated in dld -/- KV cells. Homologs of this gene have been associated with Notch signaling in Drosophila and mammalian cells through the regulation of the V-ATPase activity [2, 3]. Rbcn3a had also been associated with vesicular acidification in zebrafish hair cells [4] and with vesicular endocytosis and maturation in zebrafish neural crest migration [5].

Objective

We investigated the role of Rbcn3a in cilia length regulation.

Methods

We used a Morpholino against rbcn3a and fluorescent confocal imaging to explore cilia length. Furthermore we observed the consequences of reduced Rbcn3a in organ situs by ISH. We also performed rescue experiments by injecting rbcn3a full length mRNA at 1-cell stage dld -/- KO mutants.

Results

We showed that the downregulation of rbcn3a negatively regulates cilia length and that this can be rescued by rbcn3a overexpression in dld -/- embryos.

Conclusion

The ciliary phenotype in dld -/- mutants is partially due to the downregulation of rbcn3a. Our hypothesis is that a generalized decrease in endocytic acidification, by deregulating the V-ATPase activity, results in shorter cilia.

Authors’ Affiliations

(1)
CEDOC, Chronic Diseases Research Center, NOVA Medical School / Faculdade de Ciências Médicas, Universidade Nova de Lisboa

References

  1. Lopes SS, Lourenco R, Pacheco L, Moreno N, Kreiling J, Saude L: Notch signalling regulates left-right asymmetry through ciliary length control. Development. 2010, 137 (21): 3625-3632. 10.1242/dev.054452.View ArticlePubMedGoogle Scholar
  2. Yan Y, Denef N, Schupbach T: The vacuolar proton pump, V-ATPase, is required for notch signaling and endosomal trafficking in Drosophila. Dev Cell. 2009, 17 (3): 387-402. 10.1016/j.devcel.2009.07.001.PubMed CentralView ArticlePubMedGoogle Scholar
  3. Sethi N, Yan Y, Quek D, Schupbach T, Kang Y: Rabconnectin-3 is a functional regulator of mammalian Notch signaling. J Biol Chem. 2010, 285 (45): 34757-34764. 10.1074/jbc.M110.158634.PubMed CentralView ArticlePubMedGoogle Scholar
  4. Einhorn Z, Trapani JG, Liu Q, Nicolson T: Rabconnectin 3α promotes stable activity of the H+ pump on synaptic vesicles in hair cells. J Neurosci. 2012, 32 (32): 11144-11156. 10.1523/JNEUROSCI.1705-12.2012.PubMed CentralView ArticlePubMedGoogle Scholar
  5. Tuttle A, Hoffman TL, Schilling TF: Rabconnectin-3α regulates vesicle endocytosis and canonical Wnt signaling in zebrafish neural crest migration. PLoS Biol. 2014, 12 (5): e1001852-10.1371/journal.pbio.1001852.PubMed CentralView ArticlePubMedGoogle Scholar

Copyright

© Tavares et al. 2015

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

Advertisement