SQSTM1/p62-like Receptor Antibody Sampler Kit

Background

Autophagy is a catabolic process for the autophagosome-lysosomal degradation of bulk cytoplasmic contents (1,2). Selective autophagy targets the degradation of distinct sets of substrates and organelles and can occur through the utilization of a number of autophagy cargo receptors (3-5). Autophagy cargo receptors contain an LC3-interacting region (LIR) required for interaction with Atg8/LC3 family members targeted to the autophagosome. SQSTM1/p62-like receptors (SLRs) are a family of autophagy cargo receptors that contain domains for binding to ubiquitin. This family includes prototypical member SQSTM1/p62, NBR1, NDP52, Optineurin, and TAX1BP1. Targets of SLRs include ubiquitylated protein aggregates (aggrephagy), organelles such as mitochondria (mitoophagy) and peroxisomes (pexophagy), and intracellular bacteria (xenophagy).

Upon binding of cargo to these receptors, the complex is delivered to the autophagosome where both the cargo and receptor are degraded through the autophagic process. While some redundancy may exist among SLR family members, they can have unique activities. Many SLRs can have additional roles as scaffolding proteins for various signaling pathways. For example, SQSTM1/p62 interacts with KEAP1, a cytoplasmic inhibitor of NRF2, a key transcription factor involved in cellular responses to oxidative stress (6). Thus, accumulation of SQSTM1/p62 can lead to an increase in NRF2 activity.