The function of ENSG00000119685 (TTLL5, tubulin tyrosine ligase like 5) is as follows. Polyglutamylase which modifies tubulin, generating polyglutamate side chains on the gamma-carboxyl group of specific glutamate residues within the C-terminal tail of tubulin. Preferentially mediates ATP-dependent initiation step of the polyglutamylation reaction over the elongation step. Preferentially modifies the alpha-tubulin tail over a beta-tail (By similarity). Required for CCSAP localization to both polyglutamylated spindle and cilia microtubules (PubMed:22493317). Increases the effects of transcriptional coactivator NCOA2/TIF2 in glucocorticoid receptor- mediated repression and induction and in androgen receptor-mediated induction (PubMed:17116691). {ECO:0000250|UniProtKB:Q8CHB8, ECO:0000269|PubMed:17116691, ECO:0000269|PubMed:22493317}.