8 Transcriptional Regulation during Somitogenesis

Abstract

Publisher Summary This chapter discusses the biochemical mechanisms involved in the regulation of transcription during the development of the mouse embryo. General approach for this study involves taking genes known to act at a fairly high level in a particular genetic pathway and then to try to understand how their transcription is controlled using the power of transgenic mouse technology. In each case the objective is to identify of each of the transcription factors that control the chosen regulatory gene. It is reported that segmental identity in the vertebrate embryo is controlled by the four clusters of Hox genes. Therefore, the chapter analyzes the regulation of one such gene, Hoxb-4. One of the earliest transcriptional responses in the epithelial somite is the activation of the cascade of basic helix-loop-helix (bHLH) transcription factors that together regulate the commitment of skeletal myoblasts and their subsequent differentiation. Although there is a considerable knowledge of genes that function during somitogenesis, it is clear that many more such genes remain unknown and one has therefore sought to develop techniques that may allow the discovery of novel genes that act during defined aspects of the process.