MAPT and Alzheimer disease: However, because Tg4510 mice overexpress the frontotemporal dementia mutant P301L Tau, which has reduced ability to promote microtubule assembly and is more prone to aggregation than WT Tau [54] found in normal and AD patients, we performed reciprocal co-immunoprecipitation experiments comparing the interaction between iCLU and WT or P301L Tau in HEK 293T cells.