TRANVIA (TVA) facilitates cellulose synthase trafficking and delivery to the plasma membrane

Significance Cellulose, the most abundant biopolymer on Earth, is synthesized at the plasma membrane by cellulose synthase complexes (CSCs). The trafficking and delivery of CSCs from the Golgi apparatus to the plasma membrane is critical to maintain the level of cellulose synthesis in plants. We identified a plant-specific protein called TRANVIA (TVA) as a new component of CSC secretory compartments involved in the delivery of CSCs into the plasma membrane. This work reveals that CSCs require specific trafficking partners to facilitate their proper delivery, thus highlighting a new point at which this important process is regulated.