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Soler-Oliva, M. E.

Publications and source records attributed to Soler-Oliva, M. E..

2 recordsLinked to original sources

PLAMseq enables the proteo-genomic characterization of chromatin-associated proteins and protein interactions in a single experimental workflow.

Chromatin Immunoprecipitation (ChIP) and Co-Immunoprecipitation (CoIP) assays are common approaches to characterize the genomic localization and protein interactors, respectively, for a protein of interest. However, these approaches require the use of specific antibodies, which often face sensitivity and specificity issues. Based on TurboID, we developed PLAMseq (Proximity Labelled Affinity-purified Mass spectrometry plus sequencing), which enables, in the same workflow, to identify the genomic loci and the interacting proteome of a protein of interest. Moreover, PLAMseq can also be applied to specifically map protein interactions and ubiquitin(-like) modified proteins. We validated PLAMseq with two well characterized proteins, RNA polymerase II and CTCF, with excellent robustness and reproducibility. Next, we applied PLAMseq to characterize Histone H1 SUMOylation, which study has remained elusive due to the lack of specific reagents, and found that SETDB1 binds to SUMOylated histone H1.2 and H1.4 which also colocalize with H3K9me3 at repetitive regions of the genome.

molecular biology↗

SMARCAD1 Regulates R-Loops at Active Replication Forks Linked to Cancer Mutation Hotspots

DNA replication often encounters obstacles like the stalled transcription machinery and R-loops. While ribonucleases and DNA-RNA helicases can resolve these structures, the role of chromatin remodelers remains understudied. Through a series of in vitro and in vivo experiments, we show that the chromatin remodeler SMARCAD1, which associates with active replication forks, is crucial for resolving nearby R-loops to maintain fork stability. SMARCAD1 directly binds R-loops via its ATPase domain and associates with the replisome through its N-terminus region. Both interactions are critical for resolving R-loops within cells. Genome-wide assays reveal that cells expressing mutant SMARCAD1 accumulate significantly more R-loops than wild-type cells, particularly in regions distinct from known fork blockage-prone sites. These R-loop-enriched regions in SMARCAD1 mutants also exhibit increased mutagenesis in germline tumors, suggesting they are mutation hotspots in cancer. Therefore, SMARCAD1 acts as an R-loop sensor and resolvase at actively progressing forks, maintaining genome stability and preventing tumorigenesis.

genetics↗