Nuclear-rings and the nuclear envelope. A new interpretation of ''nuclear-pores''

True novel concepts for a new interpretation of the microscopic anatomy of the nuclear envelope are discussed that are well in agreement with recent work questioning the most widely-disseminated hypotheses concerning the permeability of the nuclear envelope. They are: a) the physical continuity of the nuclear membranes at the level of what are misleadingly known as ''nuclear pores'' and b) the existence at these sites of special structures termed ''nuclear-rings'' - whose morphology has been misinterpreted by various structural models of the traditionally termed ''nuclear pores'', basically due to the numerous artefacts created at this level by the different techniques used for preparing nuclear envelope samples for electron microscopy. The object of this article is to increase understanding of this new nuclear structure and highlight the recent progress made in this subject.