Microscopy and imaging were done at the Centre for Microscopy of Biological Objects (Institute of Cytology and Genetics, Novosibirsk, Russia) with an AxioImager.M1 (Zeiss, Jena, Germany) fluorescence microscope equipped with #49, #46HE, #43HE filter sets (Zeiss), ProgRes MF (JenaOptik, Jena, Germany) CCD camera. Software package ISIS5 version (MetaSystems, Altlussheim, Germany) was used for image acquisition and analysis.