Enables protein-glycine ligase activity, initiating. Involved in flagellated sperm motility and protein polyglycylation. Acts upstream of or within cilium assembly. Located in axoneme; microtubule cytoskeleton; and sperm flagellum. Is expressed in midbrain ventricular layer and pons ventricular layer. Orthologous to human TTLL3 (tubulin tyrosine ligase like 3). [provided by Alliance of Genome Resources, Apr 2022]