Theory 32/Cellular/Membrane fusion
Fusion Needs Protein Over Tension
The claim
Whether two cells fuse is set by the ratio of fusion protein energy to membrane tension, so a tense membrane resists fusion despite the right proteins.
01Mechanism
Fusion requires deforming two bilayers into a stalk; tension opposes the deformation, and the ratio determines whether the stalk forms.
02Prediction
Fusion should track the ratio.
03Refutation
Fusion tracking protein density alone would remove tension.