*2.5. Imaging*

The sections were examined under an epifluorescence microscope (Eclipse E600; Nikon Instruments, Melville, NY, USA), equipped with GFP (FF01-473/10), mCherry (FF01-590/20) and Cy5 (FF01-540/15) filters. Images were then acquired on a TCS-SP5 confocal microscope (Leica Microsystems, Wetzlar, Germany) using a 20x objective (Leica), with the wavelength conformation as described previously (Table 2) [17,21]. Confocal laser lines were maximal around 40% in all samples. Maximum projection images were analyzed using LASAF Leica and Fiji software ImageJ (https://imagej.net/Fiji/Downloads). All stitching and contrast adjustments were performed with LasX software (LasX Industries; St Paul, MN, USA ) and Photoshop CS5 software (Adobe Inc.; San Jose, CA, USA).

**Table 2.** Excitation and emission wavelengths for each fluorescent protein reporter


YFP: Yellow fluorescent protein; mKO: Monomeric kusabira orange; EGFP: Enhanced green fluorescent protein.
