Mitosis LabAug 1, 2023
Happy to share our in situ cryoET analysis of human chromosomes, in both G1 and metaphase. It's the work of Jon Chen , Tingsheng Liu, Shujun Cai, Cai Tong Ng, Jian Shi, and our collaborators Weimei Ruan and Uttam Surana.
https://www.biorxiv.org/content/10.1101/2023.07.31.551204v1
Show threadMitosis LabAug 1, 2023
We find diverse canonical nucleosome structures in both G1 and metaphase. These include mononucleosomes, ordered stacked dinucleosomes, and nucleosomes with gyre-proximal (albeit heterogeneous) densities. Nucleosomes have variable linker-DNA length and structure.
Show threadMitosis Lab
G1 nucleosomes concentrate in domains, like what we saw in HeLa (https://www.molbiolcell.org/doi/10.1091/mbc.E18-05-0331) and what others saw w/ super-res. Metaphase nucleosomes are not surprisingly condensed in chromatids. Megacomplexes and pockets are rare, unlike in fission yeast (https://www.pnas.org/doi/full/10.1073/pnas.1720476115).
Aug 1, 2023 at 1:05amWeb
Show threadMitosis LabAug 1, 2023
The nanoscale similarities and differences between G1 and metaphase chromatin are summarized in tables. Raw cryoET VPP data will be shared at EMPIAR. Now we need to figure out how cells control nucleosome structure and packing 🤔