RT Journal Article
SR Electronic
T1 Macromolecular and cytological changes in fission yeast G0 nuclei
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.01.11.899559
DO 10.1101/2020.01.11.899559
A1 Tan, Zhi Yang
A1 Cai, Shujun
A1 Paithankar, Saayli A.
A1 Nie, Xin
A1 Shi, Jian
A1 Gan, Lu
YR 2024
UL http://biorxiv.org/content/early/2024/04/10/2020.01.11.899559.abstract
AB When starved of nitrogen, fission yeast Schizosaccharomyces pombe cells enter a quiescent “G0” state with smaller nuclei and transcriptional repression. The genomics of S. pombe G0 cells has been well studied, but much of its nuclear cell biology remains unknown. Here we use confocal microscopy, immunoblots, and electron cryotomography to investigate the cytological, biochemical, and ultrastructural differences between S. pombe proliferating, G1-arrested, and G0 cell nuclei, with an emphasis on the histone acetylation, RNA polymerase II fates, and macromolecular complex packing. Compared to proliferating cells, G0 cells have lower levels of histone acetylation, nuclear RNA polymerase II, and active transcription. The G0 nucleus has similar macromolecular crowding yet fewer chromatin-associated multi-megadalton globular complexes. Induced histone hyperacetylation in G0 results in cells that have larger nuclei and therefore less compact chromatin. However, these histone-hyperacetylated G0 cells remain transcriptionally repressed with similar nuclear crowding. Canonical nucleosomes – those that resemble the crystal structure – are rare in proliferating, G1-arrested, and G0 cells. Our study therefore shows that extreme changes in nucleus physiology are possible without extreme reorganisation at the macromolecular level.Summary We use multiple cell-biological techniques to compare proliferating and quiescent G0 fission yeast cell nucleus transcription, histone acetylation, macromolecular packing.Competing Interest StatementThe authors have declared no competing interest.G0the quiescent stateCTD-S2PRNA polymerase II large-subunit C-terminal domain phospho-serine 2CTD-S5PRNA polymerase II large-subunit C-terminal domain phospho-serine 55-EU5-ethynyl-uridineTSATrichostatin Acryo-ETelectron cryotomography / cryo-electron tomographyMegacomplexmulti-megadalton globular complexes