ATF6 and achromatopsia: ATF6 small molecule agonists, such as ATF6-activating (AA) compounds AA147 and AA263, and antagonists, such as Ceapin-A7, have been shown to selectively modulate the ATF6 arm of the UPR pathway [108, 127, 128], Downstream targets of ATF6 may also serve as potential targets in achromatopsia.