Deep-etch analysis of adhesion complexes between gametic flagellar membranes of Chlamydomonas reinhardtii (Chlorophyceae)

The ultrastructure of adhesion complexes between gametic flagellar membrane s of Chlamydomonas reinhardtii Dangeard was analyzed using the quick-freeze deep-etch technique. The sexual agglutinin fibrils interact by forming hyb rid fibers that frequently branch, forming extensively cross-bridged meshwo rks. This pattern of interaction mimics a prominent mode of cell wall forma tion in Chlamydomonas, supporting the notion that the agglutinins evolved f rom cell wall proteins and that sexual adhesion and cell wall assembly are homologous events.