Simulcast: contiguous views of fracture faces and membrane surfaces in a single cell.

We introduce "simulcast", a new method that combines the advantages of freeze-fracture with those of "fracture-flip" (Anderson-Forsman, C., P. Pinto da Silva, J. Cell Sci. 90, 531-541 (1988)) to provide images of the fracture faces and membrane surfaces of the same membrane in a single cell. The method involves low-angle unidirectional shadowing, careful azimuthal reorientation of the replicas, flipping, and re-shadowing. Simulcast relates, in a single image, the freeze-fracture morphology of fracture faces, the nanoanatomy of membrane surfaces and the topochemistry of surface receptors/antigens.