IRE1α dissociates with BiP and inhibits ER stress-mediated apoptosis in cartilage development

Collectively, the ER stress sensors were activated during apoptosis in cartilage development, suggesting that selective activation of ER stress signaling was sufficient for induction of apoptosis. These findings reveal a novel critical role of IRE1α in ER stress-mediated apoptosis and the molecular mechanisms involved. These results suggest that activation of p-JNK1, caspase3 and CHOP was detected in developing chondrocytes and that specific ER stress signaling leads to naturally occurring apoptosis during cartilage development.