Which proteins regulate microtubule stability and assembly?

Several microtubule-associated proteins (MAPs) regulate their dynamics. Structural MAPs like MAP2, tau, and MAP4 stabilize microtubules by binding along their sides, preventing depolymerization. Motor proteins such as kinesin and dynein move cargoes along microtubules and can influence their organization. γ-tubulin forms the nucleation template at microtubule organizing centers (MTOCs), initiating assembly. 

Severing proteins like katanin and spastin cut microtubules into fragments, aiding turnover. Plus-end tracking proteins (+TIPs) such as EB1 and CLIP-170 regulate growth at the dynamic plus end, while stathmin binds free tubulin to inhibit polymerization. 

Post-translational modifications of tubulin, like acetylation or detyrosination, also modulate stability and interaction with MAPs. Together, these proteins maintain the delicate balance between microtubule growth and shrinkage essential for cell division, transport, and shape.