How Rib43a And Acetylation Of K40 Control The Rigidity Of Microtubules

Microtubules (MTs) play an important role in making the shape of the cell, so it exhibits a wide variety of properties. MTs make from the tubulin heterodimer. Tubulins form long protofilaments, which in turn form tube-like structures. Microtubule-associated proteins are proteins that bind to MTs and modify the properties of MTs. Recently, using cryo-electron microscopy, we discovered many protein binding inside of MTs in the cilia, called microtubule inner proteins (MIPs). There are many different types of MIPs. The binding position of MIPs suggest that they may be able to control the MTs properties. Besides, cryo-EM structure of the cilia suggests that post-translational modifications (PTM) play an important role in the binding of MIPs. In this research, we focused on the Rib43a, one of the MIPs binding at the profofilament ribbon region, the most stable region in the doublet microtubule. We also investigate the effect of acetylation of Lysine 40 residue, the only luminal PTM in the cilia. By using molecular dynamics simulation for them, we clarified how these factors control MTs properties.