Effect of lipid modification on fusion of sarcoplasmic reticulum vesicles

Freeze fracture technique ascertains that sarcoplasmic reticulum vesicles fuse during anisodiametric dehydration which leads to the formation of sheetlike structure of a mean extension of 5000 A. Modification of the membrane lipids by phospholipase A2 digestion or the incorporation of deoxycholate facilitates the coalescence of the vesicles, while it is completely prevented by lipid removal. Membrane fusion during anisodiametric dehydration is considered as resulting from the close contact of highly curved edges from which the membrane proteins have been excluded.