ARTICLE

ULTRASTRUCTURE AND PERMEABILITY OF NUCLEAR MEMBRANES

Joseph Wiener ¹, David Spiro ¹, and Werner R. Loewenstein ¹

¹ From the Department of Pathology and Department of Physiology, Columbia University, College of Physicians and Surgeons, New York

The fine structures of nuclear envelopes known to have different permeability properties were compared. Membranes of salivary gland cell nuclei of Drosophila (third instar) and Chironomus (prepupae), which are strong barriers to ion diffusion, and membranes of oocyte nuclei (germinal vesicle) of Xenopus and Triturus, which are much more ion-permeable, show no essential difference in size, frequency, and distribution of their membrane gaps ("pores") which could account for the marked disparities in membrane permeability. The gaps are occupied by diffuse electron-opaque material with occasional central regions of strong opacity. This material may possibly account for the high diffusion resistance of Drosophila and Chironomus nuclear envelopes, where the resistance is far too great to allow free diffusion through the gaps. But material of this kind is also present in the more permeable nuclear envelopes of Xenopus and Triturus oocytes, and there are no convincing structural differences discernible with the techniques employed.

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This article has been cited by other articles:

• Mazzanti, M., Bustamante, J. O., Oberleithner, H. (2001). Electrical Dimension of the Nuclear Envelope. Physiol. Rev. 81: 1-19 [Abstract] [Full Text]  
• Danker, T., Schillers, H., Storck, J., Shahin, V., Kramer, B., Wilhelmi, M., Oberleithner, H. (1999). Nuclear hourglass technique: An approach that detects electrically open nuclear pores in Xenopus laevis oocyte. Proc. Natl. Acad. Sci. USA 96: 13530-13535 [Abstract] [Full Text]  

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