Tom Rapaport just reported that Organelle shape can be generated by a surprisingly small set of proteins in Powers et al., Nature 2017. It is well known that the eukaryotic endomembrane system is composed of various compartments with very specific function and shape. The development of such a complex system during evolution is expected to be complex and requiring many molecular players. This new report demonstrate that just a few component can induce a tubular network from proteoliposomes. The use of GTP hydrolysis inhibitor demonstrate that maintenance of this network requires continuous membrane fusion. Conclusions from the authors:

Our results show that organelle shape can be generated by a surprisingly small set of proteins and represents an energy-dependent steady state between formation and disassembly.

Thus, it appears that evolutionarily speaking, the development of an endomembrane system might require fewer players than previously expected.