Development of a Reporter System Monitoring Regulated Intramembrane Proteolysis of the Transmembrane bZIP Transcription Factor ATF6α.

When endoplasmic reticulum (ER) functions are perturbed, the ER induces several signaling pathways called unfolded protein response to reestablish ER homeostasis through three ER transmembrane proteins: inositol-requiring enzyme 1 (IRE1), PKR-like ER kinase (PERK), and activating transcription factor 6 (ATF6). Although it is important to measure the activity of ATF6 that can indicate the status of the ER, no specific cell-based reporter assay is currently available. Here, we report a new cell-based method for monitoring ER stress based on the cleavage of ATF6α by sequential actions of proteases at the Golgi apparatus during ER stress.

Yb,Er,Eu-codoped YVO material for bioimaging with dual mode excitation.

We propose an efficient bioimaging strategy using Yb,Er,Eu-triplet doped YVO nanoparticles which were synthesized with polymer as a template. The obtained particles possess nanoscale, uniform, and flexible excitation. The effect of Eu ions on the luminescence properties of YVO:Yb,Er,Eu was investigated.