Membrane remodeling and organization: Elements common to prokaryotes and eukaryotes

Membrane remodeling processes in eukaryotes, such as those involved in endocytosis and intracellular trafficking, are mediated by a large number of structural, accessory and regulatory proteins. These processes occur in all cell types, enabling the exchange of signals and/or nutrients with the external medium and with neighboring cells; likewise, they are required for the intracellular trafficking of various cargo molecules between organelles, as well as the recycling of these structures. Recent studies have demonstrated that some elements of the molecular machinery involved in regulating and mediating endocytosis in eukaryotic cells are also present in some bacteria, where they participate in processes such as cell division, sporulation and signal transduction. However, the mechanism whereby this prokaryotic machinery carries out such functions has barely begun to be elucidated. This review summarizes recent information about the cytoskeletal and membrane-organizing proteins for which bacterial homologs have been identified; given their known functions, they may be considered to be part of an ancestral membrane organization system that first emerged in prokaryotes and which further evolved into the more complex regulatory networks operating in eukaryotes. © 2017 IUBMB Life, 69(2):55-62, 2017.