Who are you, subdistal appendages of centriole?

This review summarizes data that assign morphological, biochemical and functional characteristics of two types of structures that are associated with centrioles: distal appendages and subdistal appendages. The description of centriole subdistal appendages is often a matter of confusion, both due to the numerous names used to describe these structures and because of their variability among species and cell types. Thus, we have summarized our current knowledge in this review. We conclude that distal appendages and subdistal appendages are fundamentally different in composition and function in the cell. While in centrioles there are always nine distal appendages, the number of subdistal appendages can vary depending on the type of cells and their functional state.