Based on limited published evidence, TTLL13 is a tubulin-glutamic acid ligase that catalyzes protein polyglutamylation and binds tubulin. GO annotations indicate localization to the spindle pole and ciliary basal body, with roles in microtubule bundle formation. Recent evidence demonstrates TTLL13 functions in spindle pole integrity during keratinocyte mitosis through CFAP100-mediated recruitment to spindle microtubules, where it increases glutamylation of spindle microtubules to maintain proper chromosome 15 and support epidermal barrier development 1.