Tubulin polymerization-promoting protein is a protein that in humans is encoded by the TPPP gene. May play a role in the polymerization of tubulin into microtubules, microtubule bundling and the stabilization of existing microtubules, thus maintaining the integrity of the microtubule network. May play a role in mitotic spindle assembly and nuclear envelope breakdown. This protein has been linked to multiple sclerosis myelin lesions and CSF abnormalities in multiple sclerosis patients. This has also been linked to Parkinson's and Alzheimer's Disease.