Species predicted to react based on 100% sequence homology:Rat
Specificity / Sensitivity
Phospho-SQSTM1/p62 (Ser403) Antibody recognizes endogenous levels of SQSTM1/p62 protein only when phosphorylated at Ser403.
Source / Purification
Polyclonal antibodies are produced by immunizing animals with a synthetic phosphopeptide corresponding to residues surrounding Ser403 of human SQSTM1/p62 protein. Antibodies are purified by protein A and peptide affinity chromatography.
原厂资料:
Homology
Species predicted to react based on 100% sequence homology:Rat
Specificity / Sensitivity
Phospho-SQSTM1/p62 (Ser403) Antibody recognizes endogenous levels of SQSTM1/p62 protein only when phosphorylated at Ser403.
Source / Purification
Polyclonal antibodies are produced by immunizing animals with a synthetic phosphopeptide corresponding to residues surrounding Ser403 of human SQSTM1/p62 protein. Antibodies are purified by protein A and peptide affinity chromatography.
Background
Sequestosome 1 (SQSTM1, p62) is a ubiquitin binding protein involved in cell signaling, oxidative stress and autophagy (1-4). It was first identified as a protein that binds to the SH2 domain of p56Lck (5) and independently found to interact with PKCζ (6,7). SQSTM1 was subsequently found to interact with ubiquitin, providing a scaffold for several signaling proteins and triggering degradation of proteins through the proteasome or lysosome (8). Interaction between SQSTM1 and TRAF6 leads to the K63-linked polyubiquitination of TRAF6 and subsequent activation of the NF-κB pathway (9). Protein aggregates formed by SQSTM1 can be degraded by the autophagosome (4,10,11). SQSTM1 binds autophagosomal membrane protein LC3/Atg8, bringing SQSTM1-containing protein aggregates to the autophagosome (12). Lysosomal degradation of autophagosomes leads to a decrease in SQSTM1 levels during autophagy; conversely, autophagy inhibitors stabilize SQSTM1 levels. Studies have demonstrated a link between SQSTM1 and oxidative stress. SQSTM1 interacts with KEAP1, which is a cytoplasmic inhibitor of NRF2, a key transcription factor involved in cellular responses to oxidative stress (3). Thus, accumulation of SQSTM1 can lead to an increase in NRF2 activity.
Phosphorylation of SQSTM1 at Ser403 increases its affinity for polyubquitinated chains resulting in enhanced autophagic clearance (13,14). This site has been reported to be phosphorylated by casein kinase 2 (CK2) as well as by the innate immunity regulator TBK-1.