The Phospho-CHOP (Ser30) antibody is a specialized tool used to detect the phosphorylation of the CHOP protein at serine residue 30. CHOP (CCAAT/enhancer-binding protein homologous protein), also known as DDIT3 (DNA damage-inducible transcript 3), is a stress-responsive transcription factor induced during endoplasmic reticulum (ER) stress as part of the unfolded protein response (UPR). It is a 29 kDa protein belonging to the C/EBP family and plays a key role in promoting apoptosis under prolonged ER stress. Phosphorylation of CHOP at Ser30 is critical for its transcriptional activity, stability, or interaction with other regulatory proteins, though the exact mechanistic role remains under investigation. This modification is often linked to activation of the PERK-eIF2α-ATF4 pathway, a major UPR signaling cascade. The Phospho-CHOP (Ser30) antibody is widely used in research to study ER stress-associated diseases, including neurodegenerative disorders, diabetes, and cancer, where dysregulated UPR contributes to pathology. It enables detection of CHOP activation in models of cellular stress via techniques like Western blotting, immunofluorescence, or immunohistochemistry. Researchers rely on this antibody to evaluate ER stress levels or therapeutic interventions targeting stress pathways. Specificity validation, including knockout controls, is essential due to potential cross-reactivity with related phosphorylated epitopes.