Downregulation of mTOR signaling increases stem cell population telomere length during starvation of immortal planarians by Iglesias, M, Felix, DA, Gutiérrez-Gutiérrez, Ó, De Miguel-Bonet, MDM, Sahu, S, Fernández-Varas, B, Perona, R, Aboobaker, AA, Flores, I, González-Estévez, C