Fig. 1.

Schematic representation of the UPR signaling pathways involved in osteoblast differentiation. The black arrows indicate post-translational modifications (e.g., phosphorylation, splicing, and translocation). The red arrows indicate transcriptional regulation. Note that other cellular stresses other than protein synthesis overload may also be involved in triggering ER stress. N-OASIS N-terminal fragment of OASIS