While we commonly think of cells dividing and multiplying in our bodies, it is also possible for two cells to join together. In fact, invading viruses commonly fuse with healthy cells in order to inject foreign genes, and cellular fusion is the basic process by which sperm and egg share genetic information. Since most cells in our bodies touch one another without fusing, scientists are keen to understand what starts the fusion process and how it occurs.
One reason cell fusion is little understood is because bonding begins at the membrane, the ultra-thin envelope of molecules around each cell. All biological membranes consist of two layers of lipid molecules, called a bilayer, that have a large population of proteins embedded in them. As two-dimensional liquid films, membranes remain one of the least understood components in cells because the most powerful techniques in biochemistry -- X-ray crystallography and high-resolution nuclear magnetic resonance -- are difficult to apply.
"Membrane fusion is governed by a group of large, complex proteins, but scientists have no idea how these proteins work," said Huey Huang, Sam and Helen Worden Professor of physics and astronomy at Rice University and the senior author of the Science paper. "Our research will help scientists who are studying these proteins.
Scientists know cellular fusion begins when cell membranes form an initial junction, a tiny hole between the two cells. This junction widens over time until one single, continuous membrane envelopes the contents of both cells. Huang and co-author Li
Contact: Jade Boyd