Morphometry and ultrastructure of prismatic cristae in mitochondria of a crayfish muscle. A hypothesis of the structural principle.
Approximately 40% of the mitochondria in the sphincter muscle of the crayfish vas deferens have prismatic-type cristae. In cross section,  the angular cristae have either triangular or rhomboid profiles which are surrounded by a hexagonal array of electron-dense dots. In longitudinal section, these mitochondria exhibit both thick and thin parallel lines, which represent cristae and filaments, respectively. It is postulated that the matrix of the prismatic-type mitochondria is packed with rodlets composed of an electron-dense core and a less dense shell. Close packing of these rodlets results in the regular hexagonal dot array. Deletion of fascicles of 3 or 4 rodlets results in spaces with triangular or rectangular cross sections. Lining of these spaces with membranes results in cristae with triangular or rhomboid cross sections.
D000818:Animals; D003400:Astacoidea / Q000648:ultrastructure*; D008297:Male; D008931:Mitochondria, Muscle / Q000648:ultrastructure*; D008954:Models, Biological; D014649:Vas Deferens / Q000648:ultrastructure