– Tubulin folding cofactor A belongs to the TBCA family. It is one of four proteins (cofactors A, D, E, and C) involved in the early step of the tubulin folding pathway. These proteins can fold intermediates and finally lead to correctly folded beta-tubulin. It is believed that tubulin folding cofactors A and D play a role in capturing and stabilizing beta-tubulin intermediates in a quasi-native confirmation. Tubulin folding cofactor E binds to the cofactor D/beta-tubulin complex; interaction with tubulin folding cofactor C then causes the release of beta-tubulin polypeptides that are committed to the native state.