Like intestines in our bodies, cells have a network of pipes and tubes through which stuff is continuously passing, and from which small sausage-like entities can pinch off. These sausage-like vesicles carry molecules between factory-like compartments and to the cell’s surface. The oily skin, or membrane, and proteins surrounding the vesicles are important for maintaining their shape. Until recently little was known about the coat proteins because it is difficult to examine their structure. Pictured is a 3D computer model of a flash-frozen vesicle from a series of snapshots taken with a scanning electron microscope. False colours make the structures clearer and show for the first time the coat proteins (green, red and blue) form a net around the membrane (yellow). The model suggests the formation of coat proteins can adapt to cargoes of different sizes.
Written by Julie Webb
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