Protoplasma publishes original papers, short communications and review articles which are of interest to cell biology in all its scientific and applied aspects. We seek contributions dealing with plants and animals but also prokaryotes, protists and fungi, from the following fields: cell biology of both single and multicellular organisms molecular cytology the cell cycle membrane biology including biogenesis, dynamics, energetics and electrophysiology inter- and intracellular transport the cytoskeleton organelles experimental and quantitative ultrastructure cyto- and histochemistry Further, conceptual contributions such as new models or discoveries at the cutting edge of cell biology research will be published under the headings "New Ideas in Cell Biology". Original papers, descriptions or reviews of novel methodologies and their application in cell biology will be published under the rubric "New Methods in Cell Biology".