Enables protein-glutamic acid ligase activity and tubulin binding activity. Involved in peptidyl-glutamic acid modification. Acts upstream of or within protein polyglutamylation and regulation of blastocyst development. Located in 9+0 non-motile cilium and ciliary basal body. Orthologous to human TTLL4 (tubulin tyrosine ligase like 4). [provided by Alliance of Genome Resources, Apr 2022]