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arXiv · 1605.04054

Construction of nuclear envelope shape by a high-genus vesicle with pore-size constraint

Hiroshi Noguchi
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Abstract

Nuclear pores have an approximately uniform distribution in the nuclear envelope of most living cells. Hence, the morphology of the nuclear envelope is a spherical stomatocyte with a high genus. We have investigated the morphology of high-genus vesicles under pore-size constraint using dynamically triangulated membrane simulations. Bending-energy minimization without volume or other constraints produces a circular-cage stomatocyte, where the pores are aligned in a circular line on an oblate bud. As the pore radius is reduced, the circular-pore alignment is more stabilized than a random pore distribution on a spherical bud. However, we have clarified the conditions for the formation of a spherical stomatocyte: a small perinuclear volume, osmotic pressure within nucleoplasm, and repulsion between the pores. When area-difference elasticity is taken into account, the formation of cylindrical or budded tubules from the stomatocyte and discoidal stomatocyte is found.

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Hiroshi Noguchi. 2016-07-15. Construction of nuclear envelope shape by a high-genus vesicle with pore-size constraint. https://doi.org/10.1016/j.bpj.2016.07.010

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