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VPS72/YL1-Mediated H2A.Z Deposition Is Required for Nuclear Reassembly after Mitosis
Daniel Moreno-Andrés1,2, Hideki Yokoyama1,2, Anja Scheufen1
1Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, 52074 Aachen, Germany.
Cells
|July 26, 2020
Summary
The histone variant H2A.Z and its chaperone VPS72 are crucial for rebuilding a functional nucleus after mitosis. Downregulating VPS72 delays telophase and impairs nuclear reformation.
Area of Science:
- Cell Biology
- Molecular Biology
- Genetics
Background:
- The eukaryotic nucleus undergoes significant remodeling during mitosis, including nuclear envelope breakdown and chromosome segregation.
- While early mitotic events are well-studied, the molecular mechanisms of nuclear reassembly are less understood.
Purpose of the Study:
- To identify key molecular factors involved in the reassembly of a functional nucleus following mitosis.
- To investigate the role of histone variant H2A.Z and its chaperone VPS72 in nuclear reformation.
Main Methods:
- Utilized cell-free and cellular assays to study nuclear reassembly.
- Employed live-cell imaging and siRNA-mediated gene silencing to assess the function of VPS72.
- Investigated the involvement of VPS72 in chromatin-remodeling complexes like SRCAP and EP400.
Main Results:
- Downregulation of VPS72 using siRNA prolonged telophase in HeLa cells.
- Depletion of VPS72 or H2A.Z in vitro led to the formation of malformed and nonfunctional nuclei.
- VPS72 deposits H2A.Z, a process essential for functional nucleus formation, independent of SRCAP and EP400 complexes.
Conclusions:
- The histone variant H2A.Z and its chaperone VPS72 are critical for the reformation of a functional nucleus post-mitosis.
- VPS72 plays a vital role in H2A.Z deposition during nuclear reassembly, functioning independently of known chromatin-remodeling complexes.
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