A PEST sequence in ABCA1 regulates degradation by calpain protease and stabilization of ABCA1 by apoA-I
J. Clin. Invest. Nan Wang, et al. 111:99 doi:10.1172/JCI16808 [Go to this article.]

Figure 2
Calpain protease catalyzes PEST-dependent degradation of ABCA1. (a) Levels of ABCA1 and ABCA1delPEST in 293 cells, incubated with or without calpeptin (30 μg/ml) for 3 hours, as determined by Western blot analysis. (b) Cell surface ABCA1 or ABCA1delPEST in 293 cells with or without incubation with calpeptin (20 μg/ml) for 3 hours, as determined by biotinylation, immunoprecipitation with anti-FLAG antibody, and Western analysis with avidin–horseradish peroxidase. The data are representative of two experiments, each performed in triplicate, with similar results. (c and d) The susceptibility to exogenously added μ-calpain of ABCA1 or ABCA1delPEST metabolically labeled by [³⁵S]methionine in digitonin-permeabilized 293 cells with (d) or without (c) pretreatment with apoA-I (10 μg/ml) for 3 hours.