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TorsinA is essential for neuronal nuclear pore complex localization and maturation
Sumin Kim1,2,3, Sébastien Phan4, Hung Tri Tran5,6
1Cellular and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, MI, USA.
Nature Cell Biology
|August 8, 2024
Summary
TorsinA protein is crucial for organizing nuclear pore complexes (NPCs) in developing neurons. Its dysfunction disrupts NPC localization, impacting neuronal development and potentially causing neurodevelopmental disorders.
Area of Science:
- Neuroscience
- Cell Biology
- Molecular Biology
Background:
- Neurons, as long-lived interphase cells, face unique challenges in maintaining cellular organization.
- The regulation of nuclear pore complex (NPC) biogenesis and localization in neurons is poorly understood.
- Dysfunction of the AAA+ protein torsinA is linked to the neurodevelopmental movement disorder DYT-TOR1A dystonia.
Purpose of the Study:
- To investigate the role of torsinA in nuclear pore complex (NPC) biogenesis and spatial organization during neuronal development.
- To elucidate the mechanisms underlying NPC regulation in mature neurons.
- To determine if NPC spatial organization and biogenesis are independently regulated processes.
Main Methods:
- Generated an endogenous Nup107-HaloTag mouse line for direct visualization of NPC organization in developing neurons.
- Utilized live-cell imaging to observe NPC biogenesis and localization dynamics.
- Assessed the impact of torsinA deficiency on NPC spatial distribution and nuclear membrane morphology.
Main Results:
- Neuronal maturation is characterized by significantly upregulated NPC biogenesis.
- TorsinA coordinates the spatial organization of NPCs without altering their total density.
- Absence of torsinA leads to excessive inner nuclear membrane budding at mislocalized nascent NPC sites.
- TorsinA is essential for proper NPC localization, and its deficiency delays complete NPC formation.
Conclusions:
- NPC spatial organization and number are independently regulated.
- TorsinA plays a critical role in ensuring correct NPC localization and spatial arrangement within developing neurons.
- NPC biogenesis is a cellular process susceptible to insults associated with neurodevelopmental diseases.
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