The ATG4D antibody is a research tool used to study the function and expression of autophagy-related protein 4D (ATG4D), a key enzyme in the autophagy pathway. ATG4D belongs to the ATG4 cysteine protease family, which includes four paralogs (ATG4A-D) in humans. These enzymes are critical for autophagosome formation, primarily by cleaving pro-LC3 (microtubule-associated protein 1 light chain 3) to its active form, enabling its conjugation to phosphatidylethanolamine on autophagosomal membranes—a process essential for substrate recognition and vesicle expansion. Unlike other ATG4 isoforms (e.g., ATG4B), ATG4D exhibits distinct regulatory roles and substrate preferences, potentially functioning in selective autophagy or non-canonical pathways.
ATG4D has been linked to cellular stress responses, cancer, and neurodegenerative diseases. Its dysregulation may impair autophagic flux, contributing to disease pathogenesis. Researchers use ATG4D antibodies in techniques like Western blotting, immunofluorescence, and immunohistochemistry to detect protein expression, localization, and post-translational modifications in cells or tissues. Specificity is critical due to high homology among ATG4 family members, requiring rigorous validation to avoid cross-reactivity. Recent studies also explore ATG4D's role beyond autophagy, including interactions with apoptosis-related proteins, highlighting its multifaceted cellular functions. Developing targeted therapies or biomarkers involving ATG4D necessitates reliable antibodies to unravel its mechanistic and therapeutic relevance.