Immunostaining and In Situ Hybridization of the Developing Acoel Nervous System
The study of acoel morphologies has been recently stimulated by the knowledge that this group of animals represents an early offshoot of the Bilateria. Understanding how organ systems and tissues develop and the molecular underpinnings of the processes involved has become an area of new research. The microscopic anatomy of these organisms is best understood through the systematic use of immunochemistry and in situ hybridization procedures. These methods allow us to map, in precise detail, the expression patterns of genes and proteins, in space and time. With the additional use of genomic resources, they provide us with insights on how a group of “early” bilaterians have diversified over time. As these animals are new to the world of molecular studies, the protocols have involved a lot of new and specific adaptations to their specific anatomical-histological characteristics. Here we explain some of these protocols in detail, with the aim that should prove useful in our much-needed understanding of the origins of bilaterian animals. An anatomical sketch is provided at the beginning as a necessary guide for those not familiar with the Acoela.
KeywordsAcoela Embryos Juveniles Immunochemistry In situ hybridization FISH methodology Nervous system
The research in P. Martínez laboratory was carried out with the support of the Spanish Ministry of Science, Grants BFU2006-00898, BFU2009-07383, and BFU2012-32806. E. Perea-Atienza and B. Gavilán were supported by PhD fellowships from the Universitat de Barcelona (APIF). S.G. Sprecher acknowledges the Swiss National Science Foundation 31003A_169993. Elena Perea-Atienza and Brenda Gavilán contributed equally to the development of the described methodology. The authors would also like to thank Kathryn Apse and Prof. Seth Tyler (University of Maine) for letting us publish the acoel morphology diagrams in Fig. 1 of this chapter.
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