Shuttling RNA-binding proteins coordinate nuclear and cytoplasmic steps of gene expression. The SR family proteins regulate RNA splicing in the nucleus and a subset of them, including SRSF1, shuttles between the nucleus and cytoplasm affecting post-splicing processes. However, the physiological significance of this remains unclear. Here, we used genome editing to knock-in a nuclear retention signal (NRS) in Srsf1 to create a mouse model harboring an SRSF1 protein that is retained exclusively in the nucleus. Srsf1NRS/NRS mutants displayed small body size, hydrocephalus and immotile sperm, all traits associated with ciliary defects. We observed reduced translation of a subset of mRNAs and decreased abundance of proteins involved in multiciliogenesis, with disruption of ciliary ultrastructure and motility in cells and tissues derived from this mouse model. These results demonstrate that SRSF1 shuttling is used to reprogram gene expression networks in the context of high cellular demands, as observed here, during motile ciliogenesis.
Total RNA-seq data related to splicing analysis have been deposited in GEO under accession code GSE157269G. Polysomal, monosomal and cytoplasmic RNA-sequencing data have been deposited in GEO under accession code GSE161828. The mass spectrometry proteomics data is presented as LFQ values in the form of Excel tables in Figure 4-source data 1 and in Figure 4-figure supplement 1-source data 1. The complete raw datasests can be downloaded from ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifier PXD019859. Cilia motility data analyzed in Fiji using the custom-written ImageJ plugin "Cilility_JNH" was deposited in zenodo (https://doi.org/10.5281/zenodo.5138072).
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: This is stated in the Materials and Methods Section, 'Animal experiments'We followed international, national and institutional guidelines for the care and use of animals. Animal experiments were carried out under UK Home Office Project Licenses PPL 60/4424, PB0DC8431 and P18921CDE in facilities at the University of Edinburgh (PEL 60/2605) and were approved by the University of Edinburgh animal welfare and ethical review body.
© 2021, Haward et al.
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