Nuclei and the plasma membrane of the epidermal cells of a nematode worm embryo

Visualisation by immunofluorescence of the nuclei (in green) and the plasma membrane (in red) of the epidermal cells of a nematode worm embryo (Caenorhabditis elegans). The position of the nucleus is important for the organisation of the cells and the development of the tissues. The muscle fibres contain several hundred nuclei. These nuclei are normally located peripherally, but are displaced in the case of certain severe conditions such as centronuclear myopathies (CNM). Mutations in BIN1, the amphiphysin protein coding gene, appear to be at the origin of these diseases. In the C. elegans animal model, researchers have shown that amphiphysin can enable a link to be established between the nuclei and the cytoskeleton which maintains the shape and organisation of the cell. Through its action on the cytoskeleton, amphiphysin thus plays a vital role in positioning the nucleus within the cell, a mechanism conserved throughout the evolutionary process in the nematode, the mouse and humans but which is altered in certain myopathies.