Enzyme-mediated proximity labeling reveals the co-translational targeting of mRNA to the centrosome during mitosis.

Subcellular RNA localization is a conserved mechanism in eukaryotic cells and plays critical roles in diverse physiological processes including cell proliferation, differentiation, and embryo development. Nevertheless, the characterization of centrosome-localized mRNAs remains underexplored due to technical difficulties. In this study, we utilize APEX2-mediated proximity labeling to map the centrosome-proximal transcriptome, identifying mRNA as a novel centrosome-localized transcript during mitosis. Using a combination of drug perturbation, truncation, deletion, and mutagenesis, we demonstrate that microtubule binding of nascent MBD1 polypeptides is required for centrosomal transport of mRNA. Our data also reveal that mRNA targeting efficiency is tightly linked to the coding sequence (CDS) length. Thus, our study provides a transcriptomic resource for future investigation of centrosome-localized RNAs and sheds light on mechanisms underlying mRNA centrosomal localization.