Microtubule-induced nuclear envelope fluctuations control chromatin dynamics in Drosophila embryos

Abstract : Nuclear shape is different in stem cells and differentiated cells and reflects important changes in the mechanics of the nuclear envelope (NE). The current framework emphasizes the key role of the nuclear lamina in nuclear mechanics and its alterations in disease. Whether active stress controls nuclear deformations and how this stress interplays with properties of the NE to control NE dynamics is unclear. We address this in the early Drosophila embryo, in which profound changes in NE shape parallel the transcriptional activation of the zygotic genome. We show that microtubule (MT) polymerization events produce the elementary forces necessary for NE dynamics. Moreover, large-scale NE deformations associated with groove formation require concentration of MT polymerization in bundles organized by Dynein. However, MT bundles cannot produce grooves when the farnesylated inner nuclear membrane protein Kugelkern (Kuk) is absent. Although it increases stiffness of the NE, Kuk also stabilizes NE deformations emerging from the collective effect of MT polymerization forces concentrated in bundles. Finally, we report that MT-induced NE deformations control the dynamics of chromatin and its organization at steady state. Thus, the NE is a dynamic organelle, fluctuations of which increase chromatin dynamics. We propose that such mechanical regulation of chromatin dynamics by MTs might be important for gene regulation.
Document type :
Journal articles
Complete list of metadatas

Cited literature [37 references]  Display  Hide  Download

https://hal-amu.archives-ouvertes.fr/hal-01765088
Contributor : Carine Dou Goarin <>
Submitted on : Friday, October 26, 2018 - 12:51:46 PM
Last modification on : Monday, May 27, 2019 - 10:09:59 AM
Long-term archiving on : Sunday, January 27, 2019 - 2:22:27 PM

File

3377.full_HAL.pdf
Publication funded by an institution

Licence


Distributed under a Creative Commons Attribution 4.0 International License

Identifiers

Citation

Bernhard Hampoelz, Yannick Azou-Gros, Roxane Fabre, Olga Markova, Pierre-Henri Puech, et al.. Microtubule-induced nuclear envelope fluctuations control chromatin dynamics in Drosophila embryos. Development (Cambridge, England), Company of Biologists, 2017, 144 (4), pp.732. ⟨10.1242/dev.149575⟩. ⟨hal-01765088⟩

Share

Metrics

Record views

170

Files downloads

106