In association with LNG1, regulates leaf morphology by promoting longitudinal polar cell elongation independently of ROT3. Associates with microtubules and recruits TON1A and TON1B to the cytoskeleton through its C-terminus. Interacts (via C-terminus) with TON1A and TON1B. Localizes to cortical microtubules arrays. No visible phenotype under normal growth conditions, but the lng1 and lng2 double mutant shows reduced length of cotyledons, rosette leaves, siliques and flowers. Truncated N-terminus.