Oral Presentation 2014 International Biophysics Congress

Homotypic membrane fusion by dynamin3like GTPases (#132)

Junjie Hu 1
  1. National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China

Homotypic membrane fusion, i.e. the merging of identical membranes, plays important roles in many cellular processes. A class of dynamin-like GTPases, including atlastins/Sey1p/RHD3 on the endoplasmic reticulum (ER) and mitofusins/Fuzzy Onion/Fzo on the outer mitochondrial membrane, has been shown to mediate such reaction. These molecules share similar domain structures and membrane topology: they are anchored in the membrane by two closely spaced transmembrane (TM) segments, exposing both the N-terminal GTPase domain and the C-terminal tail to the cytosol. Mutations of these GTPases cause morphological defects of the organelles and neurodegenerative diseases in human. However, the molecular basis by which these GTPases mediate fusion is not clear. Here, we discuss recent progress in our understanding of how homotypic membrane fusion is achieved.