ABSTRACT
Lysosomes are the major degradation compartments of the cells. These acidic organelles rely on hundreds of proteins that reside in them to carry out the degradation function. Besides proteins, lipid homeostasis in the lysosome also plays key roles in lysosomal functions. The lysosomes purified with efficient lysosomal purification method are intact, they preserve the activity of the signalling molecules on the organellar membrane and they can be used for metabolomic analysis. The traditional method of lysosome purification utilizes density-gradient-based subcellular fractionation. However, most subcellular fractionation approaches bear inevitable disadvantages. For example, the lysosomes are often contaminated with other organelles. Iysosome isolation through immunoprecipitating an epitope-tagged lysosomal resident protein has been shown to potentially overcome these drawbacks of the traditional approaches. However, constitutive expression of a particular marker protein posts a risk of “spilling over” the marker to other organelles during its trafficking among different subcellular compartments, therefore introducing contamination as well.
