Centrosomal protein CEP104/ChlamydomonasFAP256 moves to the ciliary tip during cilia assembly

Abstract

SummaryThe ciliary tip has been implicated in ciliary assembly and disassembly, and signaling, yet information on its protein composition is limited. Using comparative, quantitative proteomics based on the fact that tip proteins will be approximately twice as concentrated in half-length compared with full-length flagella, we have identified FAP256 as a tip protein in Chlamydomonas. FAP256 localizes to the tips of both central pair and outer doublet microtubules (MTs) and it remains at the tip during flagellar assembly and disassembly. Similarly, its vertebrate counterpart, CEP104, localizes on the distal ends of both centrioles of nondividing cells until the mother centriole forms a cilium and then localizes at the tip of the elongating cilium. A null mutant of FAP256 in Chlamydomonas and RNAi in vertebrate cells showed that FAP256/CEP104 is required for ciliogenesis in a high percentage of cells. In those cells that could form cilia, there were structural deformities at the ciliary tips.

FLA8/KIF3B Phosphorylation Regulates Kinesin-II Interaction with IFT-B to Control IFT Entry and Turnaround

“…Toward the completion of flagellar assembly, the percentage of CrCDPK1 tip localization decreased gradually, and proximal flagellar location of CrCDPK1 was recovered (Figures 2C and 2D). The tip localization of CrCDPK1 in regenerating flagella is consistent with a report showing that CrCDPK1 is a candidate for flagellar tip proteins (Satish Tammana et al, 2013).…”

The deubiquitinating enzyme CYLD controls apical docking of basal bodies in ciliated epithelial cells

“…42), some IFT proteins 43 and, more recently, cep104/FAP256 (ref. 44). This localization of CYLD is probably independent of its DUB activity, as the staining at the cilia tip is still observed in Cyld D932 ependymal cells.…”

Protein diversity in discrete structures at the distal tip of the trypanosome flagellum

“…This points toward the involvement of CEP104 in fundamental processes that operate at flagellar tips. However, in contrast to Chlamydomonas and mammalian cells (10), depletion of ACS3/TbCEP104 in trypanosomes has no gross effect on either the presence or the length of the flagellum (SI Appendix, Fig. S5).…”

“…However, we know little about how flagellum tip structures form during flagellum assembly, how they change postaxoneme assembly, or their molecular composition. There is only a single well-characterized protein (FAP256/CEP104) known to be related to structures at the distal end of the axoneme (10,11).…”