InterPro domain: IPR007714

This domain is characteristic of cilia- and flagella-associated protein 20 (CFA20). CFA20 is a cilium- and flagellum-specific protein that plays a role in axonemal structure organisation and motility [ 1 , 2 ]. In Chlamydomonas reinhardtii, it stabilises outer doublet microtubules (DMTs) of the axoneme and may work as a scaffold for intratubular proteins, such as tektin and PACRG, to produce the beak structures in DMT1 [ 3 , 4 ].

Other proteins contain a domain with homology to CFA20. WDR90/POC16 contains such a domain in its N terminus, followed by a large C-terminal domain with multiple WD40 repeats [ 4 ]. This domain is also present in the N terminus of uncharacterised protein C3orf67.

1. Bug22p, a conserved centrosomal/ciliary protein also present in higher plants, is required for an effective ciliary stroke in Paramecium. Eukaryotic Cell 9, 645-55
2. FAP20 is an inner junction protein of doublet microtubules essential for both the planar asymmetrical waveform and stability of flagella in Chlamydomonas. Mol. Biol. Cell 25, 1472-83
3. The conserved ciliary protein Bug22 controls planar beating of Chlamydomonas flagella. J. Cell. Sci. 127, 281-7