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Cilia pp 245-254 | Cite as

Planaria as a Model System for the Analysis of Ciliary Assembly and Motility

  • Stephen M. KingEmail author
  • Ramila S. Patel-King
Protocol
Part of the Methods in Molecular Biology book series (MIMB, volume 1454)

Abstract

Planarian flatworms are carnivorous invertebrates with astounding regenerative properties. They have a ventral surface on which thousands of motile cilia are exposed to the extracellular environment. These beat in a synchronized manner against secreted mucus thereby propelling the animal forward. Similar to the nematode Caenorhabditis elegans, the planarian Schmidtea mediterranea is easy to maintain in the laboratory and is highly amenable to simple RNAi approaches through feeding with dsRNA. The methods are simple and robust, and the level of gene expression reduction that can be obtained is, in many cases, almost total. Moreover, cilia assembly and function is not essential for viability in this organism, as animals readily survive for weeks even with the apparent total absence of this organelle. Both genome and expressed sequence tag databases are available and allow design of vectors to target any desired gene of choice. Combined, these feature make planaria a useful model system in which to examine ciliary assembly and motility, especially in the context of a ciliated epithelium where many organelles beat in a hydrodynamically coupled synchronized manner. In addition, as planaria secrete mucus against which the cilia beat to generate propulsive force, this system may also prove useful for analysis of mucociliary interactions. In this chapter, we provide simple methods to maintain a planarian colony, knockdown gene expression by RNAi, and analyze the resulting animals for whole organism motility as well as ciliary architecture and function.

Key words

Axoneme Cilia Dynein Microtubule Planaria 

Notes

Acknowledgement

Our laboratory is supported by grant GM051293 (to S.M.K.) from the National Institutes of Health.

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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.Department of Molecular Biology and BiophysicsUniversity of Connecticut Health CenterFarmingtonUSA
  2. 2.Institute for Systems GenomicsUniversity of Connecticut Health CenterFarmingtonUSA

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