Merck

Analysis of rapamycin induced autophagy in Dictyostelium discoideum.

Indian journal of experimental biology (2014-04-30)
Pynskhem Bok Swer, Rakhee Lohia, Shweta Saran
ABSTRACT

Natural autophagy and autophagic cell death is being studied in the model system, D. discoideum, which has well known genetic and experimental advantages over the other known systems. There is no apoptotic machinery present in this organism which could interfere with the non-apoptotic cell death. The target of rapamycin (TOR) pathway is a major nutrient-sensing pathway which when inhibited by the drug rapamycin induces autophagy. Rapamycin was originally discovered as an anti-fungal agent but its use was abandoned when it was discovered to have potent immunosuppressive and anti-proliferative properties. It is a known drug used today for various cancer treatments and also for increasing longevity in many model organisms. It has a wide usage but its effects on other pathways or molecules are not known. This model system was used to study the action of rapamycin on autophagy induction. Using the GFP-Atg8, an autophagosome marker, it was shown that rapamycin treatment can induce autophagy by an accumulation of reactive oxygen species and intracellular free calcium. Rapamycin suppresses proliferation by induction of cell cycle arrest in the G1 phase. Taken together, the results suggest that the core machinery for autophagy is conserved in D. discoideum and it can serve as a good model system to delineate the action of rapamycin induced autophagy.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Calcium, dendritic pieces, purified by distillation, 99.9% trace metals basis
Sigma-Aldrich
Calcium, SAJ first grade, ≥99.5%
Sigma-Aldrich
Calcium, dendritic pieces, purified by distillation, 99.99% trace metals basis
Sigma-Aldrich
Calcium, turnings, 99% trace metals basis
Sigma-Aldrich
Calcium, granular, 99%
Sigma-Aldrich
Calcium, pieces, <1 cm, 99%
Supelco
Rapamycin, VETRANAL®, analytical standard
Sigma-Aldrich
Calcium, dendritic pieces, purified by distillation, 99.5% trace metals basis
Sigma-Aldrich
Rapamycin from Streptomyces hygroscopicus, ≥95% (HPLC), powder
Supelco
Sirolimus solution, 1.0 mg/mL in acetonitrile, ampule of 1 mL, certified reference material, Cerilliant®