Project description:In zebrafish embryos, the maternal transcription factors (TFs)Nanog, Pou5f3 and Sox19b activate the early zygotic gene expression. To evaluate the role of Nanog, we examined the changes in H3K27ac and H3K4me3 chromatin modifications in the MZnanog embryos mutant by maternal and zygotic Nanog.
Project description:To understand the role of Pou5f3, Sox19b and Nanog during zebrafish zygotic genome activation, RNA-seq time-series for single, double and triple maternal-zygotic (MZ) zebrafish mutants for Pou5f3, Nanog, Sox19b, as well as the wild-type.
Project description:Ikk2 regulates cytokinesis during vertebrate development (Trancriptome profiling from the wild-type and Ikk2 maternal-zygotic mutant zebrafish)
Project description:To study the function of zebrafish nuclear pores during early embryogenesis, we generated maternal zygotic double mutant of nup85;nup133 (MZnup85;nup133) using CRISPR/Cas9 and report the transcriptome-wide changes in comparison to wild-type (WT) embryos. Our analysis reveals a dramatic delay of maternal mRNA degradation and zygotic genome activation in MZnup85;nup133 embryos during maternal-to-zygotic transition.
Project description:To study the function of zebrafish Ybx1 during early embryogenesis, we generated maternal ybx1 (Mybx1) mutant using CRISPR/Cas9 and report the transcriptome-wide changes in comparison to wild-type (WT) embryos. Our analysis reveals a dramatic loss of maternal mRNA decay and zygotic genome activation in Mybx1 embryos during maternal-to-zygotic transition.
Project description:Upon fertilization, maternal factors direct development in a transcriptionally silent embryo. At the maternal-to-zygotic transition (MZT), a universal step in animal development, unknown maternal factors trigger zygotic genome activation (ZGA). In zebrafish, ZGA is required for gastrulation and clearance of maternal mRNAs, which is achieved in part by the conserved microRNA miR-430. However, the precise factors that activate the zygotic program remain largely unknown. Here we show that Nanog, Pou5f1 and SoxB1 are required for genome activation in zebrafish. We identified several hundred genes directly activated by maternal factors, thus constituting the first wave of zygotic transcription in zebrafish. Ribosome profiling in the pre-MZT embryo revealed that nanog, sox19b and pou5f1 are the most highly translated transcription factor mRNAs. Combined loss of function for Nanog, SoxB1 and Pou5f1 resulted in developmental arrest prior to gastrulation, and a failure to activate >75% of zygotic genes. Furthermore, we found that Nanog binds the miR-430 locus and together with Pou5f1 and SoxB1 initiate miR-430 expression and activity. Our results demonstrate that maternal Nanog, Pou5f1 and SoxB1 are required to initiate the zygotic developmental program and in turn trigger the clearance of the maternal program by activating miR-430 expression. Wild type and loss-of-function total mRNA sequencing of embryonic transcriptomes pre- and post-MZT; ribosome profiling pre-MZT
Project description:The exon junction complex (EJC) is composed of three core proteins Rbm8a, Magoh and Eif4a3 and is thought to play a role in several post-transcriptional processes. In this study we focus on understanding the role of EJC in zebrafish development. We identified transcriptome-wide binding sites of EJC in zebrafish via RNA:protein immunoprecipitation followed by deep sequencing (RIP-Seq). We find that, as in human cells, zebrafish EJC is deposited about 24 nts upstream of exon-exon junctions. We also identify transcripts regulated by Rbm8a and Magoh in zebrafish embryos using whole embryo RNA-seq from rbm8a mutant, magoh mutant and wild-type sibling embryos. This study shows that nonsense mediated mRNA decay is dysregulated in zebrafish EJC mutants.