Ff01 438 24 excitation filter

For short-term imaging experiments, images were acquired with an IX81 inverted microscope (Olympus, Tokyo, Japan), which was equipped with a Retiga 4000R cooled Mono CCD camera (QImaging, Surrey, Canada), a Spectra-X light engine illumination system (Lumencor, Inc., Beaverton, OR, USA), an IX2-ZDC laser-based autofocusing system (Olympus), a UPlanSApo 60x/1.35 oil objective lens (Olympus), a MAC5000 controller for filter wheels and XY stage (Ludl Electronic Products, Hawthorne, OR, USA), an incubation chamber (Tokai Hit, Fujinomiya, Japan), and a GM-4000 CO₂ supplier (Tokai Hit). The following filters and dichroic mirrors were used: for CFP, an FF01-438/24 excitation filter (Semrock, Lake Forest, IL, USA), an XF2040 445DRLP dichroic mirror (Omega, Biel, Switzerland), and an FF01-483/32-25 emission filter (Semrock); for FRET, an FF01-438/24 excitation filter (Semrock), an XF2040 445DRLP dichroic mirror (Omega), and an FF01-542/27 emission filter (Semrock). The microscopes were controlled using MetaMorph software ver. 7.8.11.0 (Molecular Devices, San Jose, CA, USA). The images were acquired every 20 s for 10 min. An amount of 100 uM H₂O₂ (Wako) or H₂O was added at 2 min, followed by the addition of 1 mM DTT or H₂O at 6 min.