Project description:The control of mRNA stability plays a central role in regulating gene expression. In metazoans, the earliest stages of development are driven by maternally supplied mRNAs. The degradation of these maternal mRNAs is critical for promoting the maternal-to-zygotic transition of developmental programs, although the underlying mechanisms are poorly understood in vertebrates. Here, we characterized maternal mRNA degradation pathways in zebrafish using a transcriptome analysis and systematic reporter assays. Our data demonstrate that ORFs enriched with uncommon codons promote deadenylation by the CCR4-NOT complex in a translation-dependent manner. This codon-mediated mRNA decay is conditional on the context of the 3â² UTR, with long 3â² UTRs conferring resistance to deadenylation. These results indicate that the combined effect of codon usage and 3â² UTR length determines the stability of maternal mRNAs in zebrafish embryos. Our study thus highlights the codon-mediated mRNA decay as a conserved regulatory mechanism in eukaryotes. zebrafish embryonic mRNA profile at 2 different stages (2 hpf and 6 hpf) in wildtype and 3 additional conditions (miR-430 inhibition, RNApol II inhibition and CNOT7 inhibition) at 6 hpf. All experiments are performed as triplicates
Project description:The control of mRNA stability plays a central role in regulating gene expression. In metazoans, the earliest stages of development are driven by maternally supplied mRNAs. The degradation of these maternal mRNAs is critical for promoting the maternal-to-zygotic transition of developmental programs, although the underlying mechanisms are poorly understood in vertebrates. Here, we characterized maternal mRNA degradation pathways in zebrafish using a transcriptome analysis and systematic reporter assays. Our data demonstrate that ORFs enriched with uncommon codons promote deadenylation by the CCR4-NOT complex in a translation-dependent manner. This codon-mediated mRNA decay is conditional on the context of the 3′ UTR, with long 3′ UTRs conferring resistance to deadenylation. These results indicate that the combined effect of codon usage and 3′ UTR length determines the stability of maternal mRNAs in zebrafish embryos. Our study thus highlights the codon-mediated mRNA decay as a conserved regulatory mechanism in eukaryotes.
Project description:This project aimed at identifying developmental stage specific transcript profiles for catecholaminergic neurons in embryos and early larvae of zebrafish (Danio rerio). Catecholaminergic neurons were labeled using transgenic zebrafish strains to drive expression of GFP. At stages 24, 36, 72 and 96 hrs post fertilization, embryos were dissociated and GFP expressing cells sorted by FACS. Isolated RNAs were processed using either polyA selection and libray generation or NanoCAGE. This is the first effort to determine stage specific mRNA profiles of catecholaminergic neurons in zebrafish.
Project description:The goal of this project was to determine the effects of acute exposition at different temperutures(18°C, 26°C and 34°C)on zebrafish.