Figure 3. Functions of actin within and around cilia.

The ciliary pocket is a hub for actin dynamics and endocytosis. Ciliary ectosomes pinch off from the tip of the ciliary membrane in response to GPCR (purple) activation and blockage of intracellular retrieval machinery [18], prior to cilia disassembly [19], and in response to mating cues in Chlamydomonas [20]. Actin accumulates at the site of membrane pinching [19]. Actin-associated proteins drebrin (green), Myosin VI (blue), and α-actinin 4 (lavender) accumulate at the ciliary tip during excision [18].