Friday, 14 October 2011
Autophagy was first discovered in yeast as a starvation response, in which cells digest portions of their cytoplasm to generate nutrients. In mammalian cells, autophagy has been shown to have additional functions and has been implicated in neuronal degradation, infectious disease, heart disease and cancer. MBL provides antibodies at a concentration of 1mg/ml and extensively validated for applications such as immunocytochemistry (ICC), immunohistochemistry (IHC), western blotting (WB), immunoprecipitation (IPP) and flow cytometry (FCM).
The most studied autophagy target is Atg8 which is present throughout the entire autophagy process. There are three mammalian homologues of yeast Atg8: LC3 (MICROTUBULE-ASSOCIATED PROTEIN 1, LIGHT CHAIN 3, ALPHA), GABARAP (GABAA receptor associate protein) and Gate-16 (Golgi –associated ATPase enhancer). Among these LC3 is the best characterized and is most commonly used as a autophagosome marker.
Yeast Atg14 has also long been known to be essential for autophagy, but its mammalian homologue Atg14L only recently has been identified. Together with Beclin1, Atg14L can bind to the kinases hVps34 and p150 to form a kinase complex. Three distinct Beclin1 complexes exist in the cell. The Atg14 complex (Beclin1, hVps34, hVps15, Atg14) promotes the autophagosome formation. The UVRAG complex (Beclin1, hVps34, hVps15, UVRAG) promotes autophagosome and endosome maturation. When Rubicon binds to a subpopulation of UVRAG proteins, the third complex (Beclin1, hVps34, hVps15, UVRAG, Rubicon) negatively regulates the process of autophagosome maturation and endosytosis.
Autophagy can be induced by serum deprivation. When such serum-starved cells are stained with an LC3 antibody and analyzed by flow cytometry, a decrease in fluorescence can be observed due to the degradation of LC3-II inside the autophagosomes.
Featured Product for flow Cytometry: Human LC3 Polyclonal Antibody (Product Code: PM036)
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