A Maternal System Initiating the Zygotic Developmental Program through Combinatorial Repression in the Ascidian Embryo.

ABSTRACT: Maternal factors initiate the zygotic developmental program in animal embryos. In embryos of the chordate, Ciona intestinalis, three maternal factors-Gata.a, β-catenin, and Zic-r.a-are required to establish three domains of gene expression at the 16-cell stage; the animal hemisphere, vegetal hemisphere, and posterior vegetal domains. Here, we show how the maternal factors establish these domains. First, only β-catenin and its effector transcription factor, Tcf7, are required to establish the vegetal hemisphere domain. Second, genes specifically expressed in the posterior vegetal domain have additional repressive cis-elements that antagonize the activity of β-catenin/Tcf7. This antagonizing activity is suppressed by Zic-r.a, which is specifically localized in the posterior vegetal domain an

SUBMITTER: Oda-Ishii I 

PROVIDER: S-EPMC4859511 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature