Tau Regulates Endoreplication in Drosophila Malpighian Tubules

Endoreplication drives polyploidy in metabolically active epithelial tissues. Here we show that loss of Drosophila Tau increases nuclear size and DAPI fluorescence in principal and stellate cells of the Malpighian tubule, indicative of elevated DNA content. A similar increase is observed in the salivary gland, another polyploid tissue. These findings reveal a previously unrecognized role for Tau in restraining endoreplication in non-neuronal epithelia.