Volume 4 Supplement 1

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

Open Access

Pkd2 affects the architecture of zebrafish left-right organizer

  • R Jacinto1,
  • P Sampaio1,
  • M Roxo-Rosa1 and
  • S Lopes1
Cilia20154(Suppl 1):P84

DOI: 10.1186/2046-2530-4-S1-P84

Published: 13 July 2015

Background

Dorsal anterior clustering (DAC) of motile cilia in the left-right organizer (LRO) is crucial for normal fluid flow dynamics and correct laterality in zebrafish [1]. We directly demonstrated that charon/dand5 transcription is negatively regulated by strong flow in zebrafish LRO [1] which suggests that LRO cells have the ability to sense fluid flow and influence gene expression patterns, but how? Pkd2 ion channel is a good candidate because it participates in a mechanosensory complex that senses fluid flow and induces a calcium inward flux in kidney cells [2] and in nodal cells [3]. In agreement, mouse and zebrafish mutants for Pkd2 have LR defects [4, 5]. However, Pkd2 is also involved in cell polarity during migration [6] and in extracellular matrix deposition [7] implying a role for Pkd2 in cell morphogenesis.

Objective

Determine whether Pkd2 knockdown affects DAC of ciliated LRO cells.

Methods

dnah7 morpholino [1] was injected to generate static cilia without affecting DAC [1]. Each embryo was screened for static cilia by high-speed videomicroscopy. In parallel, Pkd2 knockdowns were imaged for flow dynamics followed by quantification of anterior / posterior cilia number through two-photon microscopy.

Results

Pkd2 knockdown, contrary to Dnah7 knockdown, caused a remodelling in the LRO architecture by disrupting DAC. Moreover, Pkd2 knockdown resulted in abnormal fluid flow as a consequence of defective DAC.

Conclusions

Comparing Dnah7 and Pkd2 knockdowns we concluded that Pkd2 mediated pathway affects LRO morphogenesis by a mechanism that seems to be independent of its role in fluid flow mechanosensation. Meaning that Pkd2 triggers additional responses from those caused by LRO flow.

Supported by FCT-ANR/BEX-BID/0153/2012 grant.

Authors’ Affiliations

(1)
CEDOC, NOVA Medical School

References

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Copyright

© Jacinto 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.

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