Development of individual placodes from their common primordium

Schlosser, Gerhard. (2021). Development of individual placodes from their common primordium In Gerhard Schlosser, Development of sensory and neurosecretory cell types: Vertebrate cranial placodes, Volume 1. Boca Raton: CRC Press.

Abstract

Chapter 4 discusses how the pre-placodal ectoderm (PPE), once it is established, gives rise to different types of placodes. Whereas adenohypophyseal, olfactory and lens placodes will form from its anterior portion, otic, lateral line and epibranchial placodes will form from the posterior PPE, with profundal and trigeminal placodes sandwiched in between. The subdivision of the PPE into individual placodes is a complex process comprising several phases. The first phase involves the multistep regional specification of different placodes within the PPE due to the region-specific induction of different transcription factors. In a second phase, individual placodes separate from each other by a combination of transcriptional cross-repression, apoptosis, and cell movements. The chapter summarizes the development of placodes during these two phases, placing particular emphasis on the role of transcription factors during the first phase, which is most relevant for our understanding of how different placodal cell types are generated in a region-specific manner.

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CRC Press

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Attribution-NonCommercial-NoDerivatives 4.0 International

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Zoology (Book Chapters)