Centriole-enriched microtubule-binding protein involved in centriole biogenesis (PubMed:20844083, PubMed:25131205, PubMed:27185865). Essential for the generation of the distal portion of new-born centrioles in a CENPJ- and CEP120-mediated elongation dependent manner during the cell cycle S/G2 phase after formation of the initiating cartwheel structure (PubMed:27185865). Required for the recruitment of centriolar proteins, such as POC1B, POC5 and CEP135, into the distal portion of centrioles (PubMed:27185865). Also required for centriole-to-centrosome conversion during mitotic progression, but is dispensable for cartwheel removal or centriole disengagement (PubMed:25131205). Binds to and stabilizes centriolar microtubule (PubMed:27185865). Interacts (via ALMS motif) with microtubules; this interaction is direct. Associates with both of the converted centrioles during G1 but becomes more enriched at the newly formed daughter (or unconverted) centrioles during S, G2, and early M phases (PubMed:25131205, PubMed:32060285). In early S phase, localized at the procentriolar microtubule wall and enriched at the proximal ends of the centrioles in CENPJ- and CEP135-dependent manner (PubMed:27185865). Colocalizes with SASS6 and CEP250 proteins (PubMed:25131205). Colocalizes with CEP135 and CEP192 at the centrosomes (PubMed:27185865). Associates with interphase microtubules and mitotic spindles (PubMed:27185865). Colocalizes with centriolar acetylated tubulin (PubMed:25131205). The N-terminal and the ALMS motif-containing C-terminal regions are essential for CEP295-mediated centriole elongation. Extended N-terminus. Truncated N-terminus. Truncated N-terminus.