Nuclear growth and import can be uncoupled

Pan Chen, Sampada Mishra, Haritha Prabha, Sourabh Sengupta, Daniel L. Levy

Research output: Contribution to journalArticlepeer-review

1 Scopus citations

Abstract

What drives nuclear growth? Studying nuclei assembled in Xenopus egg extract and focusing on importin α/β-mediated nuclear import, we show that, while import is required for nuclear growth, nuclear growth and import can be uncoupled when chromatin structure is manipulated. Nuclei treated with micrococcal nuclease to fragment DNA grew slowly despite exhibiting little to no change in import rates. Nuclei assembled around axolotl chromatin with 20-fold more DNA than Xenopus grew larger but imported more slowly. Treating nuclei with reagents known to alter histone methylation or acetylation caused nuclei to grow less while still importing to a similar extent or to grow larger without significantly increasing import. Nuclear growth but not import was increased in live sea urchin embryos treated with the DNA methylator N-nitrosodimethylamine. These data suggest that nuclear import is not the primary driving force for nuclear growth. Instead, we observed that nuclear blebs expanded preferentially at sites of high chromatin density and lamin addition, whereas small Benzonase-treated nuclei lacking DNA exhibited reduced lamin incorporation into the nuclear envelope. In summary, we report experimental conditions where nuclear import is not sufficient to drive nuclear growth, hypothesizing that this uncoupling is a result of altered chromatin structure.

Original languageEnglish (US)
Pages (from-to)ar1
JournalMolecular biology of the cell
Volume35
Issue number1
DOIs
StatePublished - Jan 1 2024
Externally publishedYes

PubMed: MeSH publication types

  • Journal Article

Fingerprint

Dive into the research topics of 'Nuclear growth and import can be uncoupled'. Together they form a unique fingerprint.

Cite this