The structure of junctions between lens fiber cells.

Junctions which have been isolated from bovine lens may correspond to the tongue-and groove interdigitations observed between intact cells. These junctions have an overall thickness of 13-14 nm, a striking undulating surface topology, and contain protein subunits of congruent to 27 000 daltons which are arranged in a 6.6-6.7-nm square lattice in the plane of each membrane. A similar square-lattice structure has been observed in junctions from fragments of intact rate lens. Junctions from both sources are structurally different from "typical' gap junctions.