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SMC translocation is unaffected by an excess of nucleoid associated proteins in vivo

ABSTRACT: Genome organization is important for DNA replication, gene expression, and chromosome segregation. In bacteria, two large family of proteins, nucleoid-associated proteins (NAPs) and the SMC complexes, play important roles organizing the genome. NAPs are abundant DNA-binding proteins that can bend, wrap, bridge and compact DNA, while SMC complexes load on the chromosome, translocate on the DNA, and extrude DNA loops. How SMC loop extrusion is influenced by various NAPs remains unknown. In this study, we expressed a collection of representative prokaryotic chromosome-associated proteins in Bacillus subtilis, which introduce distinct DNA structures and pose different challenges for SMC loop extrusion. By fluorescence microscopy and chromatin immunoprecipitation experiments, we observed that these proteins bound to the genome in characteristic manners. Through genome-wide chromosome conformation capture assays, we found that the SMC complex can traverse these DNA-binding proteins without slowing down. Our findings reveal that the DNA loop extrusion activity of the SMC complex is unaffected by the chromosome-associated proteins and highlight the robustness of SMC motors on the busy chromatin.

ORGANISM(S): Bacillus subtilis PY79

PROVIDER: GSE269767 | GEO | 2025/01/17

REPOSITORIES: GEO

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