LC3 traps were developed to isolate endogenous LC3/GABARAP proteins from mammalian cells (1). LC3 traps were engineered to contain multimeric LC3-interacting regions (LIRs) to increase their affinity for LC3/GABARAP proteins in various cell lines. LC3 traps W are based in 8 consensual LIR sequences with predominant hydrophobic amino-acids W typically found in the autophagy receptor p62. These LIRs are known to display affinity and specificity towards one or several LC3/GABARAP family members. LC3 traps W show binding preference towards LC3A and LC3B proteins in mammalian cells, and for LGG2 in C. elegans model. The affinity of LC3-traps was measured using microscale thermophoresis (MST) and estimated in the low nanomolar range (1).
B Molecular proposes LC3 trap W tagged with GST that can be attached to glutathione agarose affinity columns. LC3-traps can be easily use in GST-pull down assays to capture LC3/GABARAP proteins and cellular factors directly or indirectly associated to these ubiquitin family members from mammalian cells but also equivalent molecules LGG2 in C. elegans or ATG8 in S. cerevisiae models (1, 2). In addition to that, LC3-traps are incorporated in different in vitro and cell-based assays/kits developed by B Molecular that will be commercialized in the near future.