Rapamycin is unique in its ability to inhibit lymphokine induced cell proliferation at the G1 and S phase as well as an irreversible cellular arrest at the G1 phase in S. cerevisiae cells. It also exhibits selective signal blocking leading to the activation of p70/85 S6 kinase, which is potentially due to the inhibition of FRAP autophosphorylation or protein kinase activity. Angiogenesis inhibition is also exhibited, possibly through the inhibition of the Akt pathway. Induces autophagy in yeast and mammalian cell lines.