O75460

IRE1α plays a crucial role in the unfolded protein response (UPR), a cellular stress response activated when misfolded or unfolded proteins accumulate in the endoplasmic reticulum (ER). This response is vital for maintaining cellular homeostasis and preventing apoptosis under stress conditions. IRE1α, along with IRE1β homolog, is localized in the ER lumen and features a transmembrane domain spanning the ER membrane, as well as a cytosolic Ser/Thr kinase domain. Upon activation, IRE1α undergoes oligomerization and trans-phosphorylation, which enhances kinase activity and leads to UPR-targeted gene transcription. This process is essential for proper protein folding and ER function restoration. Additionally, IRE1α is involved in Jun N-Terminal Kinase (JNK) phosphorylation, thereby activating the cellular MAP kinase pathway, which further underscores IRE1α′s importance in cellular signaling and stress response mechanisms.