The ESCRT machinery directs quality control over inner nuclear membrane architecture
Raakhee Shankar1, Molly M Lettman1, William Whisler1
1Department of Biomolecular Chemistry, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA.
Cell Reports
|January 19, 2022
Summary
The endosomal sorting complex required for transport (ESCRT) machinery maintains nuclear envelope structure by pruning inner nuclear membrane invaginations. Impaired ESCRT function causes defects, impacting genome integrity and leading to embryonic lethality.
Area of Science:
- Cell Biology
- Developmental Biology
- Genetics
Background:
- The nuclear envelope (NE) reseals after mitosis, compartmentalizing the genome.
- The endosomal sorting complex required for transport (ESCRT) machinery is known to aid NE resealing.
- The role of ESCRT in maintaining inner nuclear membrane structure is less understood.
Purpose of the Study:
- To investigate additional functions of the ESCRT machinery in maintaining inner nuclear membrane structure.
- To explore the ESCRT machinery's role during the first embryonic division in C. elegans.
Main Methods:
- Utilized the stereotypic first division of the C. elegans embryo.
- Examined the effects of impaired ESCRT function on nuclear envelope reformation and expansion.
- Investigated combined effects of ESCRT inhibition and nuclear lamina mutations.
Main Results:
- Impaired ESCRT function led to defects in pruning inner nuclear membrane invaginations.
- Combined ESCRT inhibition and nuclear lamina defects significantly perturbed NE architecture.
- Chromosome segregation defects and embryonic lethality were observed under combined inhibition.
Conclusions:
- ESCRT-mediated remodeling is crucial for inner nuclear membrane structure maintenance.
- ESCRT function is vital for nuclear envelope morphology and genome preservation during early development.
- Links between ESCRT, NE structure, and genomic integrity were highlighted.
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