Anti-ATG4B Rabbit Monoclonal Antibody for WB, IF, ELISA - Q9Y4P1

Core Product Specifications and Parameters

Biological Background: ATG4B Function and Localization

• ATG4B (also known as APG4B, AUTL1, autophagin-1) is a key cysteine protease that regulates autophagy by mediating proteolytic processing and delipidation of ATG8 family proteins, essential for macroautophagy, non-canonical autophagy, and mitophagy. Related references: PMID:15169837, PMID:15187094, PMID:17347651, PMID:33773106, PMID:33909989

• It cleaves the C-terminal amino acids of ATG8 homologs (MAP1LC3A/B/C, GABARAP, GABARAPL1/2) to expose a conserved glycine, a prerequisite for their conjugation to phosphatidylethanolamine (PE) and insertion into autophagosomal membranes. Related references: PMID:15169837, PMID:15187094, PMID:17347651

• ATG4B also acts as a delipidating enzyme, deconjugating PE from ATG8 proteins to facilitate their recycling; it additionally processes ATG8 proteins on single-membrane structures during non-canonical autophagy. Related references: PMID:15187094, PMID:19322194, PMID:29458288, PMID:33909989

• In mitophagy, ATG4B promotes phagophore growth independently of its protease activity by regulating ATG9A trafficking to mitochondria and enabling ER-phagophore contacts for lipid transfer. Related references: PMID:33773106

• Among the four mammalian ATG4 paralogs (ATG4A–D), ATG4B is the major protease for ATG8 activation, but exhibits relatively weak delipidation activity compared to ATG4A and ATG4D. Related references: PMID:29458288, PMID:30661429

• Subcellularly, ATG4B localizes to the cytoplasm, cytosol, autophagosomes, endoplasmic reticulum, and mitochondria, consistent with its multifaceted role in autophagy and related pathways.

• Post-translational modifications including acetylation, phosphorylation, S-nitrosylation, and glycation have been reported, potentially regulating its enzymatic activity and subcellular distribution.

Experimental Guidance and Technical Tips

• The immunogen corresponds to a peptide within residues 200-300 of human ATG4B, a region located in the catalytic domain. Antibody reactivity may be influenced by post-translational modifications or conformational states.
• For Western blotting, ATG4B migrates at approximately 44 kDa. Endogenous levels may vary; consider using autophagy inducers (e.g., starvation, rapamycin) to enhance detection.
• In immunofluorescence applications, ATG4B shows a punctate cytoplasmic distribution that can colocalize with autophagosome markers (e.g., LC3) and mitochondrial markers under mitophagy conditions. Validate specificity in knockout cell lines.
• The antibody has been reported to cross-react with mouse and rat ATG4B; however, sequence alignment of the immunogen region should be verified for other species.
• ELISA applications may be used for quantification; consider a sandwich ELISA format with a matched antibody pair.

CamelBio: Your One-Stop Sourcing Bridge

CamelBio provides diagnostic manufacturers and laboratories with one-stop access to high-quality IVD raw materials and comprehensive technical support, accelerating your projects from concept to clinic. With expertise in autophagy and mitochondrial research, CamelBio offers validated antibody pairs, optimized monoclonal and polyclonal antibodies, and bulk ancillary reagents tailored to your assay development needs. Rely on our dedicated sourcing and consulting services to secure rare targets and streamline your procurement process.