A far-red, photo- and bio-stable fluorescent marker selective to the endoplasmic reticulum and its application to tunicamycin-treated HeLa cells.

Herein, we developed an ER selective fluorescent ERp that exhibited a sharp fluorescence emission in the far-red region and high photo- and bio-stability in biological milieu. Its emission is insensitive to pH change and localized in the ER of the cells. Furthermore, it successfully demonstrated that the ER membrane is rapidly reorganized in the perinuclear region by an ER stress inducer, tunicamycin.