Deadenylation by the <scp>CCR</scp>4‐<scp>NOT</scp> complex contributes to the turnover of <i>hairy</i>‐related <scp>mRNA</scp>s in the zebrafish segmentation clock

<jats:sec><jats:label /><jats:p>In the zebrafish segmentation clock, <jats:italic>hairy/enhancer of split</jats:italic>‐related genes <jats:italic>her1</jats:italic>,<jats:italic> her7</jats:italic>, and <jats:italic>hes6</jats:italic> encodes components of core oscillators. Since the expression of cyclic genes proceeds rapidly in the presomitic mesoderm (<jats:styled-content style="fixed-case">PSM</jats:styled-content>), these <jats:italic>hairy</jats:italic>‐related <jats:styled-content style="fixed-case">mRNA</jats:styled-content>s are subject to strict post‐transcriptional regulation. In this study, we demonstrate that inhibition of the <jats:styled-content style="fixed-case">CCR</jats:styled-content>4‐<jats:styled-content style="fixed-case">NOT</jats:styled-content> deadenylase complex lengthens poly(A) tails of <jats:italic>hairy</jats:italic>‐related <jats:styled-content style="fixed-case">mRNA</jats:styled-content>s and increases the amount of these <jats:styled-content style="fixed-case">mRNA</jats:styled-content>s, which is accompanied by defective somite segmentation. In transgenic embryos, we show that <jats:italic><jats:styled-content style="fixed-case">EGFP</jats:styled-content></jats:italic> <jats:styled-content style="fixed-case">mRNA</jats:styled-content>s with 3′<jats:styled-content style="fixed-case">UTR</jats:styled-content>s of <jats:italic>hairy</jats:italic>‐related genes exhibit turnover similar to endogenous <jats:styled-content style="fixed-case">mRNA</jats:styled-content>s. Our results suggest that turnover rates of <jats:italic>her1, her7,</jats:italic> and <jats:italic>hes6 </jats:italic><jats:styled-content style="fixed-case">mRNA</jats:styled-content>s are differently regulated by the <jats:styled-content style="fixed-case">CCR</jats:styled-content>4‐<jats:styled-content style="fixed-case">NOT</jats:styled-content> deadenylase complex possibly through their 3′<jats:styled-content style="fixed-case">UTR</jats:styled-content>s in the zebrafish PSM.</jats:p></jats:sec>