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Rouse, J.

Publications and source records attributed to Rouse, J..

4 recordsLinked to original sources

Chemo-phosphoproteomic profiling with ATR inhibitors berzosertib and gartisertib uncovers new biomarkers and DNA damage response regulators

The ATR kinase protects cells against DNA damage and replication stress and represents a promising anti-cancer drug target. The ATR inhibitors (ATRi) berzosertib and gartisertib are in clinical trials for treatment of advanced solid tumours as monotherapy or in combination with genotoxic agents. However, the pharmacodynamic ATR biomarker phospho-CHK1 has shown limited sensitivity in for quantitative assessment of ATR activity in clinical trials. Therefore, better biomarkers are needed, and with this in mind we carried out quantitative phospho-proteomic screening for ATR biomarkers that are highly sensitive to berzosertib and gartisertib. Screening identified novel ATR-dependent targets in three broad classes: i) targets whose phosphorylation is highly sensitive to ATRi; ii) novel targets with known genome maintenance roles; iii) novel targets whose cellular roles are unclear, including SCAF1. We show that SCAF1 interacts with RNAPII in a phospho-dependent manner and suppresses homologous recombination in cells lacking the BRCA1 tumour suppressor. Taken together these data reveal potential new ATR biomarkers and new genome maintenance factors.

biochemistry↗

The histone chaperone activity of SPT2 controls chromatin structure and function in Metazoa

Histone chaperones control nucleosome density and chromatin structure. In yeast, the H3-H4 chaperone Spt2 controls histone deposition at active genes but its roles in metazoan chromatin structure and organismal physiology are not known. Here we identify the Caenorhabditis elegans orthologue of SPT2 (CeSPT-2) and show that its ability to bind histones H3-H4 is important for germline development and transgenerational epigenetic gene silencing, and that spt-2 mutants display signatures of a global stress response. Genome-wide profiling showed that CeSPT-2 binds to a range of highly expressed genes, and we find that spt-2 mutants have increased chromatin accessibility at these loci. We also show that human SPT2 controls the incorporation of new H3.3 into chromatin. Our work reveals roles for SPT2 in controlling chromatin structure and function in Metazoa.

molecular biology↗

Interaction with C21ORF2 controls the cellular functions of the NEK1 kinase

NEK1 is a pleiotropic protein kinase implicated in mitosis, ciliogenesis and DNA repair but little is known about its regulation or targets. Its relevance for human health is underscored by the association of NEK1 mutations with human diseases including axial spondylometaphyseal dyplasia (SMD) and amyotrophic lateral sclerosis (ALS). Mutations in the C21ORF2 gene are associated with a similar pattern of human diseases, suggesting close functional links with NEK1. Here we report that in unperturbed, untransformed cells, endogenous NEK1 and C21ORF2 form a tight complex that does not appear to contain other proteins. A small acidic domain "CID: C21ORF2 interaction domain" at the C-terminus of NEK1 is necessary and sufficient to interact with C21ORF2, and pathogenic mutations in this region disrupt the complex. AlphaFold modelling predicts with high confidence an extended binding interface between a leucine-rich repeat (LRR) domain in the N-terminal half of C21ORF2 and a stretch of the NEK1-CID; mutating residues mediating electrostatic interactions within this interface disrupts the NEK1-C21ORF2 interaction. This model also explains why pathogenic mutations disrupt the complex. We go on to show that the kinase activity of NEK1 and its interaction with C21ORF2 is critical for NEK1 function in cells. These data reveal C21ORF2 as a regulatory subunit of NEK1, illuminating our understanding of how this kinase is regulated and NEK1-C21ORF2-associated diseases.

biochemistry↗

Epilepsy kinase CDKL5 is a DNA damage sensor which controls transcriptional activity at DNA breaks

Mutation of the CDKL5 kinase gene leads to the seizure-prone neurodevelopmental condition CDD (CDKL5 deficiency disorder) and is the most common genetic cause of childhood epilepsy. However, the phospho-targets and roles of CDKL5 are poorly understood, especially in the nucleus. We reveal CDKL5 as a sensor of DNA damage in actively transcribed regions of the nucleus, which phosphorylates transcriptional regulators such as Elongin A (ELOA) on a specific consensus motif. Recruitment of CDKL5 and ELOA to DNA damage sites, and subsequent ELOA phosphorylation, requires both active transcription and synthesis of poly-ADP ribose to which CDKL5 can bind. Critically, CDKL5 is essential for transcriptional control at DNA breaks. Therefore, CDKL5 is a DNA damage-sensing regulator of transcription, with implications for CDKL5-related human diseases. One sentence summaryCDKL5 is a DNA damage-sensing kinase that modulates transcriptional activity near DNA breaks.

cell biology↗