Plan apochromat 60 1.40 oil dic objective

Fluorescence microscopy of transfected HeLa cells was performed with an Axio Observer.Z1 microscope (Zeiss), equipped with a Zeiss Plan‐Apochromat 60 × /1.40 Oil DIC objective. During live cell imaging, cells were maintained at 37 °C using an objective heater (Bioptechs). A standard Zeiss filter set (38HE) was used. Images were taken with a Zeiss 12bit ‘AxioCam MRm’ camera, and digital images were processed using Zeiss AxioVision Software.

HeLa cells were grown to about 50% confluence on 35-mm glass-bottom Petri dishes (Wellco) supplemented with Dulbecco's Modified Eagle Medium containing 10% fetal bovine serum (Invitrogen). Twenty-four hour later, the cells were transfected with EGFP-tagged TASK-4 constructs using Fugene 6 (Roche). The cells were cultured at 37°C for 12–72 h in an incubator supplied with 5% CO₂/95% air. Microscopy and imaging were performed with a Zeiss Axio Observer.Z1 microscope equipped with a Zeiss Plan-Apochromat 60×/1.40 Oil DIC objective and a standard Zeiss filter set for EGFP (38HE). For DsRed-tagged constructs, a filter set of AHF Analysentechnik AG (Tübingen, Germany) (F46-005) was used. Images were taken with a Zeiss 12bit ‘AxioCam MRm’ camera, and digital images were processed using Zeiss AxioVision Software. Digital unmixing was performed before analyzing co-localization.

HL‐1 cells were grown on glass cover slips in 35‐mm Petri dishes (Nunc), transfected as described above, and fixed with 4% PFA + 4% sucrose. Imaging was performed utilizing a Zeiss imaging platform comprising an Axio Observer.Z1 microscope equipped with a Plan‐Apochromat 60×/1.40 Oil DIC objective and a standard filter set for EGFP (Zeiss 38HE). Digital images were taken with a 12 bit “AxioCam MRm” camera and processed using the AxioVision Software.