Dynamics of nuclear structure for embryonic gene regulation and development

 

Kei MIYAMOTO (Faculty of Agriculture, Kyushu University)

宮本　圭　（九州大学 農学研究院）

 

The germ cell nucleus is reprogramed to an embryonic state after fertilization. This epigenetic reprograming has been extensively studied by focusing on spatiotemporal alternations of embryonic chromatin. It has recently become clear that the nucleus itself, which stores chromatin, undergoes dynamic structural changes during the reprograming process (1-3). Here, we have examined the dynamics of nuclear structure in preimplantation embryos, and found a unique physical property of the nucleus at the 2-cell stage in mouse. The loss of a nucleoskeleton protein is responsible for the soft and plastic 2-cell nuclei. Furthermore, the physically distinct nuclear state is needed for establishing embryonic chromatin and activating embryonic genes. Thus, through quantitative analyses of embryonic nuclear properties, we have revealed a new mechanism regulating early embryogenesis. In this presentation, I will show the mechanism of nuclear structure regulation mediated by nucleoskeletal proteins and discuss its contribution to early development.

 

Reference:

1. Masahito T, Sakanoue R, Takasu A, Watanabe N, Shimamoto Y, Miyamoto K. Transition to the structurally vulnerable nuclear state is an integral part of mouse embryonic development. bioRxiv. 2023
2. Gunasekaran S, Miyagawa Y, Miyamoto K. Actin nucleoskeleton in embryonic development and cellular differentiation. Curr Opin Cell Biol. 2022, 76, 102100
3. Okuno T, Li WY, Hatano Y, Takasu A, Sakamoto Y, Yamamoto M, Ikeda Z, Shindo T, Plessner M, Morita K, Matsumoto K, Yamagata K, Grosse R, Miyamoto K. Zygotic Nuclear F-Actin Safeguards Embryonic Development. Cell Rep 2020, 31(13), 107824