TTLL1 Gene - Tubulin Tyrosine Ligase Like 1 | Function, Mutations & Disease

The TTLL1 gene encodes a member of the tubulin tyrosine ligase-like (TTLL) family. This protein functions as a tubulin polyglutamylase, catalyzing the addition of glutamate side chains to tubulin, a key post-translational modification that regulates microtubule stability, dynamics, and interactions with microtubule-associated proteins. TTLL1 is involved in the formation of the polyglutamate chain on the C-terminal tail of alpha-tubulin. It is expressed in various tissues, with highest levels in brain and testis. Mutations in TTLL1 have been associated with primary ciliary dyskinesia and other ciliopathies.

Tissue Expression

Cell Line Expression

Hotspot Mutations

Mutation functional classification

• Tubulin polyglutamylation pathway

• Microtubule cytoskeleton organization

• Ciliary assembly and function

TTLL1 is a 658-amino acid protein that localizes to the cytosol and microtubules. It catalyzes the polyglutamylation of alpha-tubulin, adding glutamate side chains that modulate microtubule stability and interactions. The protein contains a conserved TTL domain essential for enzymatic activity. TTLL1 is part of a larger complex that includes other TTLL family members. Its expression is enriched in brain and testis, consistent with roles in neuronal and ciliary function.